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 'A ’N 'ssn3DjA s — ■ ! 
 
 aaaNia jishs 
 
i 
 
A 
 
 COMPENDIUM 
 
 OF THE 
 
 ANATOMY 
 
 OF TKE 
 
 HUMAN BODY. 
 
 INTENDED PRINCIPALLY FOR THE USE OF STUDENTS; 
 
 BY ANDREW FYFE. 
 
 IN TWO VOLUMES. 
 
 VOL. II. 
 
 This Edition is prefixed with 
 
 A Compendious History of Anatomy, 
 
 And tbs 
 
 Ruvschian Art and Method 
 
 Of making Preparations to exhibit the Structure of the 
 Human Body, illufiratcd with a Reprefentation of the 
 
 Quicksilver Tray and its Appendages, 
 
 Which are not in the London Edition. 
 
 PRINTED AND SOLD BY JAMES HUMPHREYS, 
 
 Ac che N.W. Corner of Walnut and Dock-ftreets. 
 
COMPENDIUM 
 
 OF THE 
 
 ANATOMY 
 
 HUMAN BODY, 
 
 INTENDED PRINCIPALLY FOR. THE USE 
 OF STUDENTS. 
 
 By ANDREW FYFE. 
 
 IN TWO VOLUMES. 
 
 VOL. II. 
 
 'RENTED AND SOLD BY JAMES HUMPHREYS, 
 At the N. W. Corner of Walnut and Dock-ftreets. 
 
PART IV. 
 
 OF THE 
 
 VISCERA, 
 
 AND 
 
 ORGANS OF THE SENSES. 
 
 OF THE -COMMON INTEGUMENTS. 
 
 The Cuticle. 
 
 ^ir^KF, Cut id’. Epidermis, or Skarf-Skir . , is a thin femitranf- 
 X parent infenlible Membrane, which covers the Skin, and 
 adheres to it by fmall Vafcular Filaments. 
 
 The Cuticle is readily [epa.ra.ted from the Cutis by boiling 
 water, or by putrefaction, and in the living body, by the appli- 
 cation of blitters. 
 
 It is not every where of the fame denfity, being even in the 
 Foetus, thickelt in the Palms and ' Soles ; in which parts, the 
 thicknefs is afterwards much increafed by pr.efiure. 
 
 The External Surjace is marked by Furro-ivs, which corref- 
 pond with tliofe in the Cutis Vera. 
 
 Upon the Surface of the Body it is perforated by the termina- 
 tion of the Exhalent VetTels, — which throw out the Perfpirable 
 Matter, and which, when increafed, is confidered by molt of the 
 modern Phyflologifts, as forming the Sweat; — by the ends of 
 the Excretory DuCts, which are found in particular parts of the 
 Skin; — by the beginnings of the„Abforhents, which take in 
 certain Subrtauces applied to the Surface of the Skin ; and — by 
 the different flairs. 
 
4 
 
 Tlie Perforations, or Pores, are mofi evident upon the Palms 
 and Soles, and upon the Nol'e, Ears, and external parts or Ge- 
 iteration. 
 
 The Cuticle covers the Skin through its whole extent, excep- 
 ting under the Nails. 
 
 From the External Surface of the Body, it is reflected in- 
 wards, to line, the large Paffages ; as the Alimentary Canal, the 
 T rachea, the Urethra, Vagina, &c. 
 
 In thefe Pafl'ages, however, the Cuticle becomes lefs uniform 
 in its texture ; and in feme of them, as in the Stomach, is either 
 awanting, or is lo much changed in ftrufture, as to have the ap- 
 pearance of beinCT f 0 . 
 
 From the Surface of the Cuticle, certain Proceffes are fent 
 into the Skin, which line the Paffages by which the Cutis is per- 
 Jorated. 
 
 Many opinions have been advanced concerning the origin of 
 the Cuticle : — the Intel! and molt probable is, that it is iornted 
 by a condenfatien of the Corpus Mucofum, or by the Exticmi- 
 lies of Excretory Veffels; — its denfity, however, is fuel), that 
 no veffels can be traced in it, either by the Eye or by the affilt- 
 ance of glaffes. 
 
 The Cuticle ferves to preteft the fenfible parts under it ; and 
 to regulate the proportion of the Fluids thrown out or taken in 
 by the Surface cf the Skin ; — paiticularly to prevent too great a 
 dtgiee of evaporation. 
 
 Corpus Mucosum. • 
 
 The Corpus Mucofum has been commonly called Rete Mucofum, 
 from the fuppofition that it is formed of a Mucous Net work, and 
 is fituated under the Cuticle which it connects to the Cutis 
 Vera. 
 
 It is compofcd of the teiminations of extremely minute Veffels 
 paffinr, between the Cutis and Cuticle, which are fui rounded by 
 a Mucilaginous or Vifcid Subfiance, properly called Corpus Mu- 
 cofum. 
 
 It is the chief caufe of that variety of colour which chat'after- 
 ifes the natives of d fferent climates, ar,d different people of the 
 fame climate, being white, or rather of a light-grey femi tiar.f- 
 parent colour in the European, black in the Ethiopian, brown in 
 the Aliatic, &c. 
 
 It is thicker and frenger in the Negro than in the white pev- 
 fon, and can be readily separated in the fcimer into two Layers. 
 
 It covers every part of the Surface of the Cutis, exceptmg 
 below the Nails, where it is awanting ; and is of f'uch a light 
 colour in the Palms and Soles of the Negro, as to have been fup- 
 pofed by Ionic authors to be deficient there all’o. 
 
5 
 
 Its origin has not yet been fufficiently ascertained, nor is it fully 
 determined what particular purpofes it ferves. . 
 
 Among other purpofes, however, it contributes to preferve 
 the Itruflure of the tender Vellels, Duffs, and Papillae, placed 
 between the Cutis and Cuticle ; and in the Negro, it is fup- 
 pol’ed to ferve as a defence againtl the heat of the climate, by 
 preventing the rays of the Sun from penetrating the Skin. 
 
 Cutis Vera. 
 
 The Cutis Vera, or Skin, propei iy fo called, lies immediately 
 under the Corpus Mucofum, and gives a general covering to the 
 whole Body. 
 
 It is formed of Fibres intimately interwoven, and running in 
 every dueftion, and is fo plentifully {'applied w th Nerves and 
 Blood- Veffels, that the fmallelt punfttire cannot be ma.le in any 
 part of it, without occafioning pain and bringing Blood. 
 
 The Blood-Veffels of the Cutis are fo numerous, as to appear 
 to form almolt the whole of its Subitance, and are of fuch a iize 
 as to be readily injefted. 
 
 It is ftrong and elalflc, and may be elongated in every direc- 
 tion, after which it recovers its former dlineniions. 
 
 It forms the body of the Skin, and is that part in Quadrupeds 
 of which Leather is made. 
 
 The outer pa<t of it is denfe and firm, the inner loofe, and 
 gradually degenerating into the common Cellular Subitance. 
 
 It is thicker and loofer on the polterior than on the anterior 
 part of the Body, an-d thicker and .firmer in the Palms and Soles 
 than in the other parts or the extremities. 
 
 The colour of the Cutis alio differs in different parts of the 
 body, in proportion to the quantity of Blood in the extreme Vei- 
 l'd?, and to the thiunefs of the Cuticle. 
 
 At the edge of the Eye-lids , the red part of the I ips, and mar- 
 gin of the Anus, the Cutis becomes i'o immediately and remarka- 
 bly thin, as to appear to be loll. 
 
 Upon the Surface of the Cutis, fmall Eminences are obferved, 
 ca.led Papilla:, Papilla Nervo fa, and Papilla Pyramidales j the 
 term being borrowed from the Papilla? of the fonsue, which 
 were firft dilcoyered, and to which the name is rnoft applicable. 
 
 They are ccnlkierecl as forming the Organ of Touch, from 
 their being extremely fenfible ; and from their being very Vaf- 
 cular, tney are alio regarded as furnilhlng a paflage to part of 
 the Perfp'rable Matter. 
 
 The Papilla are rnofc evident in the Palms and Soles, where 
 they are placed in double rows upon the ridges, which on the 
 points of the Fingers and Toes, generally run in a fomewhat 
 Ipiral and parallel direction. 
 
 V Ob, II, A 2, | 
 
6 
 
 The Ridges ate fuppofed to defend the Papillae, and to increafe 
 the Suitace for Perlpiration. 
 
 In fome places, as in the red part of the Lips, the Papillae are 
 termed Villi, from their refemblance to the p.le of Velvet. 
 
 Various kinds of folds are obferved in the Sk>n ; fome depend- 
 ing upon the form of the Cellular Subftance, as in the Hips j 
 others on Mufcular Contraction, as in the Fore-head ; and 
 others on Articular Motion, as at the Joints of the extremities, 
 —particularly thofe of the Fingers and Toes;— and thefe folds 
 are thinner than the reft of the Skin, to allow eafy motion. 
 
 In an inflamed Skin, as in the cafe of Small-pox, a Reticular 
 Texture of Vefiels is obferved, which can be eafily injefted, and 
 has been coniidered by fome as the Corpus Mucofum, and by 
 others as an additional Cuticle ; — but no fitch appearance is to be 
 met with in the found Skin. 
 
 ff he Cutis Vera ferves to cover and give form to the Body, it 
 unites the different parts, and defends them from injury. It 
 forms (he External Organs of Senfatiun or of Touch, and gives 
 paffage to the Fluids which are Perfpired or Ablorbed. 
 
 APPENDAGES OF THE SKIN. 
 
 Nails. 
 
 The Nails were formerly regarded as a continuation of the 
 Papillae of the Cutis, but are now more generally confidered as 
 a continuation of the Cuticle. 
 
 They are removed along with it by boiling water, or by ma- 
 ceration. 
 
 Like the Cuticle alfo, they are infenfible, are renewable after 
 having been feparated, and have no evident Veflels. 
 
 They differ from it, however, in ftrufture, being formed of 
 Plates, and thefe of Longitudinal Fibres, which are ciofely com- 
 pared. 
 
 They begin by a fquare root, a little before the laft Joint of 
 the Fingers and Toes. 
 
 When feparated from the Skin, they are tranfparent like 
 Horn, but are coloured in the living Body by the Veffels of the 
 Cutis, to which they adhere, and from which they derive their 
 
 nonriftiment. 
 
 They are fixed at their roots to a femilunar fold of the Cutis, 
 and are there covered by a refle&ion of the Cuticle, which firmly 
 adheres to them. 
 
 They grow from the roots, and not from the points. 
 
 The nails ftrengthen and defend the ends of the Fingers and 
 Toes, and thereby ferve as Buttreftes. 
 
7 
 
 In the Fingers they increafe the power of apprehenlton, being 
 ufetul in laying hold of minute objects. 
 
 Hairs. 
 
 The Hairs arife by roots or bulbs, which are iituated in the 
 Cellular Subftance under the Skin. 
 
 The Bulbs are of various lhapes in different parts of the B jdy, 
 and have Blood-Veffels difperled upon them for their nourifh- 
 ment. 
 
 Each of the Bulbs has two Membranes, or Capfules, conta : n- 
 ing an Oily Fluid between them, which gives colour to the Hair, 
 and for want of which, as in advanced life, or in certain difeales, 
 the Hair is fuppofed to change its colour, and become white. It 
 may be remarked, however, that the Hair, after being cut off, 
 continues uniformly to prelerve its colour. 
 
 The body of the Hair coniifts of fraaller hairs inclofed in a 
 Membrane, and is fomewhat of the nature of the Nails. Like 
 them alfo, it grows only from the root. 
 
 The ufe of the Hair is not yet fully known. — It ferves in general 
 for the ornament, warmth, or protection of the different parts on 
 or near which it is placed. 
 
 Sebaceous Ducts or Follicles, and Miliary 
 Glands. 
 
 The Sebaceous Follicles derive their name from the Fluid they 
 contain becoming like Suet, after acquiring a certain degree of 
 confiftency, or being inl'piffated by ftagnation. 
 
 They are feated under the Cutis, and are found in greateft 
 abundance in thole parts which are expofed to the air, or to at- 
 trition ; as in the Nofe, Ears, Nipples, Groins, and external 
 Parts or Generation. 
 
 The Sebaceous, or Miliary Glands , are fo called from their 
 contents, and from their refemblance to Millet Seeds, and are 
 feated in the Axilla. 
 
 Other Mil. ary Glands are deferibed by Authors as being 
 placed under the Skin over the whole Surface ot the Body, and 
 as ferving for the fecretion of Perfpirable Matter but they are 
 not demonftrable to fuch a general extent ; and the Sweat tscon- 
 fidered as being derived from another fource. 
 
 Thefe Follicles and Glands fecrete a fluid which ferves to lu- 
 bricate the Skin, and defend it from the inclemency of the weather, 
 or from the effects of fri&ion. 
 
 Membrana Cellularis, or Tela Cellulosa, or 
 Reticular, or Cellular Substance. 
 
 This is generally confidered as one of the Integuments, 
 though common to thefe and to the other parts of the Body. 
 
8 
 
 It is compofed of a fine web, formed of many Membranes join 
 ed irregularly together, and thefe made up of Cells, which com- 
 municate freely with each other wherever they are found. 
 
 It is very elalfic, may be drawn out to a confiderable extent, 
 after which it t'uddenly recoils, and may be condenied or com- 
 pared to a great degree. 
 
 It lines the Skin, covers the Mufcles in general, and enters in 
 between their different Fibres; — is an univerfal covering to all 
 the other parts, and even enters into the compofition of almoft 
 every one of them. 
 
 It is thickelf where the parts are moftexpofed to preffure, as in 
 the Hips, Palrns, and Soles. 
 
 The different Cells of which it is compofod, are conftantly 
 moinened by an Intel ltitial Fiuid, and in many parts of the 
 Body are fi led with Fat. 
 
 It has little cr no lenfibility, can be handled freely, or cut or 
 punftured without giving pain. 
 
 It ferves to conneft parts to each other, — but fo as to prevent 
 them from growing together ; — it covers them, fupplies them with 
 fhcaths to move in, and contains the Fat. 
 
 Corpus Adiposum, Adeps, Pinguebo, or Fat. 
 
 The Fat is lodged in the common Cellular Subftance, but with- 
 cut communicating with it, and s made upot Mafles compcfed of 
 I'm a 1 1 Vehicles containing the Fat, and thefe are furrounded by a 
 net work of Blood- VcfTels, £ om which the Fat is fuppofed to be 
 fecieterl, with ut the intervention of Glands. 
 
 The Ve.fules are not found to have any communication with 
 each other, n»r have any Excretory Duffs yet been perceived in 
 them, — he Fat being fuppufed to tranfude from the Cells. 
 
 Ii is of different canfifeney in different paits i f the Body : In 
 the living Eody it is generally fluid, though in fome parts it ap- 
 proaches" to a iulid, and is altogether of "this nature in the dead 
 Body. 
 
 In the Bones it forms the Marrow, which has been formerly 
 defer i bed . 
 
 The Fat is chiefly fituated immediately under the Skin, and 
 covers almoft the whole Sm face of the Body. It is aifo found 
 between the different Mufcles and Fibres of Mufcles, — within 
 the Orbits, anu in the Cheeks, — in the Subftance of the Main- 
 ffiae, and about the Heart. 
 
 \ It abounds ir. the Abdomen, about the Kidneys, Loins, Omen- 
 ti\m, and Mefentery; — and in the Joints it forms the Subflan- 
 ce^ called Glands of the Joints, already mentioned. 
 
 The Fat is awatiling in the Scrotum, Penis, and Eye-Lids, 
 and is found only in final 1 quantity in the Fore-head, or about 
 the Joints, where, from its bulk, it would have been jjpnconvuH- 
 
 V 
 
eut. — It is alio awanting in the Subffance of the Vifcera fituated 
 n the great Cavities of the Body; as the Brain, Lungs, Liver, 
 Spleen, Kidneys, &c. 
 
 The Fat ferves to lubricate every part of the Body to which it 
 is connefted, and facilitates the adlion of the Muicles. It fills 
 the Interflices, fo as to give form and fmoothnefs, and guard 
 againtl prefl’ure. It ferves all’o as a refervoir of nourifhment. 
 
 Panniculus Car.nosus, 
 
 Defcribed by the Ancients as an 
 Additional Covering. 
 
 This is a general Covering found in the Quadruped, and 
 formed by a thin Subcutaneous Mufcle, which ferves to agitate 
 the Skin. 
 
 It is found only in certain parts of the Human Body; as in 
 the Fore-head, where it is formed by the Occipito, Frontalis 
 Ivlufcle ; and in the Neck, where it is formed by the Platyfnva 
 Myoides, 
 
 •OOOOOOOO® OOOOOOOO' 
 
 OF THE BRAIN . 
 
 THE term Brain is applied to the whole of that Mafs which, 
 with its furrourtding Membranes, fills the Cavity of the Crani- 
 um ; and is larger in Man, in proportion to the fize of the body, 
 titan in any other animal. 
 
 The Membranes of the Brain were called Meninges and Ma- 
 ters by the Ancients, from an idea that they gave birth or ori- 
 gin to all the other Membranes of the Body. 
 
 They co nil if of the Dura Mater , Tunica Arachnoidea, and Pia 
 Mater. 
 
 The Dura Mater, named from its being of a firmer tex- 
 ture than the other two Membranes, . ir.clofes the Brain and all 
 its Appendages, and lines the different parts of the Cranium. 
 
 It is compofcd of one Membrane, whk h, in feveral parts, 
 is diviiible by maceration into two, or even more layers of Fi- 
 bres. 
 
10 
 
 The texture of the Dura Mater is very denfe. It is the 
 thickeft and ftrongefl Membrane of the B -dy, and is c :: r fed 
 of Tendinous like Fibres, winch have a Aiming appearance, 
 particularly in its inner Surface. In many parts !•->« Fibre* 
 run in a variety of dire&ions, and deculfate eac, ^ '.Affer- 
 ent angles. 
 
 The Dura Mater adheres every where to the Surface of ti e 
 Cranium, in the fanie manner as tin- . .. . S •. ■ a c the 
 
 Bones in the other parts of the Body it : *rw« 
 nefled at the Sutures and Ftratnim’. tit an .'-h'ewkere ; an.-, fo 
 much more firmly in Children tr 
 
 it from the Cranium, it is apt to bring along with it fome of the 
 Fibres of the Bone to which it is a 1 :' rube.! ■ • -In t! e adult, the Se- 
 paration of the Bone from the Mem Inane is •••is dii • :c 
 fequence of many of the Fibres being obhterau d 
 
 The inner Surface of the Dura Mater, which is remarkably 
 
 finooth, is in clo'c con tail with te Train, but adheres only where 
 the Veins go into the ’ i tufes,— ■ and v lul • ; to by a Fluid dis- 
 charged through its V< iH-ls, v, h guards the Brain from dan- 
 ger, according as it may be abetted by the different flutes of 
 Refpiration. 
 
 The Dura Mater ferves as a defence to the Brain, and fup- 
 plies the place of a PerioJUum to the infide of the Bones of the 
 Cranium, giving nourifhment 10 them,— -as is evident from the 
 numerous drops of JJlo.ud which appear after removing the 
 Skull-cap. 
 
 From the inner fide of the Dura Mater, Procejfes are fen t off, 
 which divide the Brain into certain parts, and lerve to keep it 
 Heady, viz. 
 
 I. The Falx, Superior Longitudinal Procefs, or Septum Cere- 
 bri, which is formed by a doubling of the Dura Mater, and is 
 fituated between the Hemifpheres of the Brain. 
 
 It begins at the middle of the Sphenoid, and Crifta Gal 1 i of the 
 Ethmoid Bone, and runs along the upper and middle part of the 
 Head, adhering firfl to the Frontal, then to the joining of the 
 Parietal, and afterwards to the middle of the Occipital Bone. 
 
 In its paffage it becomes gradually broader, cxiends from the 
 Cranium to near the Corpus Callufum, and terminates behind in 
 the middle of the Tentorium. 
 
 It luns from behind forwards in a Araight direction, and has 
 fome refembh.nce in fliape to a Sickle 01 Scythe , from which cir- 
 cumltance it has obtained the name of Falx. 
 
 Between the under edge of the Falx and Bafe of the Cranium, 
 there is a large /pace, of an oval faun, occupied by that pait of 
 the Brain which is common to the two Hemifpheres. 
 
 The Falx fupports the Tentorium, and prevents., the two tides 
 of the Brain from prefling upon each other. , 
 
11 
 
 II. The Tentorium CEREBELLi,or Tranjverfe Septum, ol 
 Lateral Procejfes of the Dura Mater. 
 
 The ’Tentorium is continued laterally from the Falx, is con- 
 ne£ted behind to the inner Tranfverfe Ridges and Grooves of 
 the Occipital Bone, and at the fore and outer edges, to the 
 Ridges and great Angles of the Temporal Bones, and terminates 
 at the Pofterior Ciinoid Procefs of the Sphenoid Bone. 
 
 Between the middle and inner edges of the Tentorium and 
 pofterior Ciinoid Procefs of the Sphenoid Bone, there is a large 
 Notch, or Foramen Ovale, where the Brain and Cerebellum are 
 united, or where the Tuber Annulare is chiefly fituated. 
 
 The Tentorium keeps the Falx tenfe and forms a floor or vault 
 over the Cerebellum, which prevents the Brain from prefling up- 
 on it. 
 
 III. The Fai.x Minor, or Septum Cerebelli, which is placed 
 between the Lobes of the Cerebellum. It defcends from the 
 underand back-part of the Falx in themiddle of the Tentorium, 
 adheres to the inferior Longitudinal Spine of the Os Occipitis, 
 and terminates infenfibly at the edge of the Foramen Magnum 
 of that Bone. 
 
 Betides the Procefles of the Dura Mater already defcribed, 
 there are four of inferior confideration, two of which are fituated 
 it the fldes of the Sella Turcica and two at the edges of the Fora- 
 mina Lacera. 
 
 Several other Procefles nafs out at the different openings of 
 he Cranium, to be connected to the Pericranium, or to accom- 
 pany the Spinal Marrow and Nerves : — Thele of the laft defcrip- 
 :ton fhall be afterwards taken notice of. 
 
 Tiie Arteries of the Dura Mater are derived partly from the 
 External Carotids, and partly from the internal Carotids and 
 Vertebrals. 
 
 The Veins of this Membrane are of two kinds. One fet of 
 them, like the Veins in other parts of the body accompany the 
 Arteries ; — the others are termed Sinufes and differ from Veins 
 only in this, that they are of a triangular Figure, and inclofed 
 in a doubling of the Dura Mater, which is fo tenfe over them, 
 as to become affefled in confequence of the preflure from fur- 
 rounding parts. 
 
 In the bottom of the Sinufes are fmall Tranfluerfe chords ter- 
 med Chorda Wilisii, which may add a little to their ftrength, and 
 afllft in preventing them from being too much diftended. 
 
 The Sinufes lerve to carry the Blood from the Brain, and con- 
 vey it to the Veins of the Neck, for which purpofe they are pro- 
 perly fitted, their covering from the Dura Mater giving them 
 ftrength, and their frequent communications preventing congef- 
 tiou. 
 
.12 
 
 1 be Principal Sinuses are, 
 
 I. The Superior Longitudinal Sinus, which begins at 
 the Crilta Galli of the Ethmoid Bone, runs along the upper 
 edge of the Falx, becomes gradually larger in its progrefs, and 
 terminates in the Lateral Sinules. 
 
 II. TheToRCULAR Herophjli, or fourth Sinus of the An- 
 cients; the term Torcular is applied to it from the fuppofition 
 that the Blood is fqueezed in that Sinus as in a Wine prefs. — ■ 
 It is chiefly formed of the Vena Galeni, runs between the Falx 
 and Tentorium, and and terminates with the former Sinus in the 
 beginning of the Lateral Sinufes. 
 
 III. The Two Lateral Sinuses, which are formed by 
 the Longitudinal and Torcular Sinufes, run in depreflions of the 
 Occipital and Temporal Bones, firft tranfverfely, then in a 
 winding di reftion downwards, and terminate at the Bafe of the 
 Cranium, in the beginning of the Internal Jugular Veins. 
 
 Befides the Sinufes mentioned above, feveral others of lefs con- 
 fideration will be pointed out in the particular defcription of the 
 -Veins. 
 
 The Nerves of the Dura Mater are fo very minute, that they 
 have not as yet been dillinftly traced, and it is found to poflefs 
 very little fenfibility in the found date. 
 
 Upon the fde of the fuperior longitudinal Sinus, and contigu- 
 ous parts of the Brain, there ar t numerous fmall Granulations, 
 of a vohitijh colour, called Glandules Pachioju. 
 
 Befides thefe Granulations, there are others of the fame name, 
 of a Flejhy colour, fi tainted on certain parts of i he outer Surf ace of 
 the Dura Mater, and frequently proje&ing fo much as to form 
 deep pits in the Skuil. 
 
 The nature of thefe Granulations is ftill unknown, — By i'ome 
 fhev have been fuppofed to belong to the Lymphatic Syftem. 
 
 The Tunica Arachnoidea, named from its cob-web ap- 
 pearance, is an exceedingly thin, tender, and tranfparent Mem- 
 brane, in which no vefl'els have been hitherto obferved. 
 
 It is fpread uniformly over the Surface of the Brain, ir.clo- 
 fing all its Convolutions, without insinuating itfelf between any' 
 of them. 
 
 At the upper part of the Brain, it adheres fo clofely to the fub- 
 jacent Coat by fine Cellular Subfiance, that it can fcarcely be 
 Separated from it ; but in diffeient parts of the Bafe of the Brain, 
 ■particularly about the Tuber Annulare and Medulla Oblongata, 
 it is merely in cor.tafi with the Membrane under it, and may 
 readily be railed from it by the aflifiance of the Blow-pipe. 
 
 The Tunica Arachnoidea, like the Cuticle, covers and de- 
 fends the parts under it. 
 
 The Pi a Mater, named from its tendernefs, is fomewhat of 
 i the nature of the former covering, but is extremely Vafcular 
 
13 
 
 It covers the Brain in general, enters double between all its . 
 Convolutions, and lines the diff rent Civities called Ventricles. 
 
 It ferves to contain and fup to t the VelTVIs of the Brain, and 
 allows them to divide into luch minute part-, as to prevent the 
 Blood from entering the tender Subttance of this Vifcus with too 
 great force. 
 
 The Arteries of the Pia M ter are the fame with thofe of the 
 Brain and ire derived from the Imernai Carotids <tnd Vertebrals. 
 
 The fains differ m no ref peri from thofe of the other Vifcera, 
 exceotin ; in this, that they do not accompany the Arteries. 
 
 The Bran ts J vide! into Cerebrum, Cerebellum, Tuber An- 
 nulare and Medulla Oblongata. 
 
 Cerebrum. 
 
 The Cereb:-um is (ituated in the upper part of the Cranium, 
 which u compleely fills. 
 
 It s div de l into two halves, termed Hemifpberes, which are 
 fepn rated from each other by the Falx. 
 
 Each of t ie Hemfpheres is of an oval form, or they fome- 
 whatrelem ole an egg cut into two longitudinal helves. The in- 
 ner tides are Hit, the upper and outer parts convex, and the un- 
 der Surface nebular. 
 
 Tne under S i face is divided into tvjo Anterior, tvjo Lateral, 
 and ttvo Pojh’-'ior Lobes , or ProceJJ'es. 
 
 The Anterior Lobes zre limited m the fore-part of the Bafe of 
 the Cranium. 
 
 The Lateral or Middle Lobes, are lodged in the FofLe formed 
 by tiie feinpor .1 and Sphenoid B ones. 
 
 Th e Pole ior Lobes are placed over the Cerebellum, and are 
 fepar.ited from t by the Tentorium. 
 
 Between the Anterior and Lateral Lobes, there is a Fwrovj 
 formed by the Anterior Clinch'd Precedes of the Sphenoid Bone, 
 which has been termed Foffa, or Fiffura Magna Siruvii. 
 
 Tne Surface of the Brain is divided into many turnings or 
 windings, termed Circumvolutions , which run in various direc- 
 tions, and are of different iizes and lengths on different parts of 
 the Brain. 
 
 The Circumvolutions are every where connected to the Pia 
 Mrtei by an infinite number of final! Veifcls,— called by 
 Ruysci-i, To/nentum Cerebi , — which run into the Subffunce of 
 the Brain ; as may be readily leen, upon ieparaung the Circum- 
 volutions a li tie from each other. 
 
 Between the Hem ipneies a white Subftance is obferved, cal- 
 led Corpus Cailofum, from its being a little firmer than. the reft of 
 the Brain. — It goes acrofs the Biain, under the Falx, and is 
 merely a continuation of Medullary Subilance, running hort- 
 
 VOL, II. B 
 
14 
 
 zontally, and joining the twb Tides of the Hemifpheres to each 
 other. 
 
 In the middle of the Corpus Callofutn there is a longitudinal 
 Raphe, with a Medullary Cord on eaci: fide, from which many 
 tranfverfe Freaks iffue. Thefe Cords, like the Corpus Cal- 
 lofum itfelf, become gradually broader towaids the poller i or ex= 
 tremity. 
 
 An horizontal Seflion, a little above the middle height of the 
 Brain, or upon a level with the Corpus Callolum, Thews the di- 
 vision of the Subfiance of the Brain into outer or inner, or Cor- 
 tical and Medullary parts. 
 
 The outer Subllance is termed Ciueritious, from its being of 
 a greyijlj or ajh colour, — though a little tinged with brown; — 
 and Cortical, from its furrounding tire inner part of the Brain, as 
 the Bark does the Pith cf a Tree 
 
 It is termed by Jome Authors Glandular, and by others Secre- 
 tory, from a fuppofition that a Fluid was fecreied in ir. 
 
 The Ciueritious Snbfxance covers the Brain in general, and en- 
 ters deep between its Convolutions, is of a foft confidence, and 
 6*inpofed of numerous final 1 Vefils carrying red Blood ; but 
 it is uniform, and without any appearance of a Fibrous texture. 
 
 The inner SubFance is termed JVhite or Medullar . , and is con- 
 fidcred as giving origin to the different Nerves. It has been by 
 fome called Excretory, having been ftippofed to be formed of hol- 
 low Tubes continued fiom the Veflels of the Cortical part; — 
 but no Cavit es have ever been obl'erved in the loft Fibres of 
 which it is computed. 
 
 It is greater in quantity, and fome what firmer in texture, than 
 the Ciueritious SubFance, and is i'o intimately connected as to 
 appear to be a continuation of it. — The fort Fibres or Freaks of 
 the Medullary Matter, run in general in a parallel and tranfverfe 
 dire£tion. 
 
 In many parts of the Ciueritious Subfiance, Medullaiy Mat- 
 ter appears ; and, on the o ntrary, in different parts of the Me- 
 dullary Subllance, Ciner tious Matter is found ; the two being 
 frequently blended together in the form of Freaks. See Monro 
 on Nervous Syjfem. 
 
 The Centrum Ovale of Vieussens. This is the Medullary 
 Subftance of the Brain, forming a kind of Nucleus, which is 
 feen after removing the Cineritious Subllance, and all the Me- 
 dullary parts mixed with it, which be between tile Cortical Con- 
 volutions. 
 
 . To obtain a proper view .of the Centrum Ovale, the .Nucleus 
 ought to be cut in fuch a manner as to prelerve the Corpus C:d- 
 lofum, and the fame convexity with that of the general convexity 
 of the Brain. 
 
15 
 
 The Centrum Ovale forms an arch or roof over the two Lateral 
 Ve. it ■ , .he - ii er part of this roof, which is i'mooth and 
 
 unifor l . . c M'.nic'.'US .lie upper part of thele Ventricles. 
 
 Vi..u s-:: ,s < n lidered the Centrum Ovale as the great Dif- 
 pc-.. cj tb An’ null Spirits. 
 
 f Vr r R : c l £ s tire Brain are four in number, two of 
 which are er.iir.t Lateral. 
 
 The four Veil ■ icier nave their tides contiguous to each other, 
 are chietiv to-, nr:, of Medullary Matter, and are lined with a 
 continuation •■= P'u Mater, winch d. tiers from that covering 
 the e rertir Surface of the Brain, m having fewer \elTels dif- 
 peried upon it. 
 
 They are conftantiv moiftened by a Fluid, which prevents 
 their uppofite fides from adhering to each other. 
 
 The uf of the Ventricles, like many other parts of the Brain, 
 is (till unknown. 
 
 The Lateral , formerly called Superior Ventricles, are fituated 
 in the Hemilpheres, one in each, and run Horizontally in the fame 
 direction with he Hemilpheres tlrenrlelves. 
 
 They are of an irregular form, hying under the Centrum 
 Ovale, and have each three winding corners, compared to Rani’s 
 Horns, which are therefore called Cornua. 
 
 The Anterior Cornua are feparated only by the Septum Luci- 
 dum. 
 
 The Poferior Cornua , called alio Digital Cavities , are at a 
 considerable diftance front each other, but approach nearer at 
 their pointed extremities ; while the inferior Cornua, the begin- 
 ning of which is feen, run downwards arid forwards, and termi- 
 nate in the Lateral Lobes of the Brain. 
 
 In each of thePofterior Cornua there is an Elongation, which 
 terminates in a point, and i-s called Ergot by the French, from 
 its refemblanee to the Spur of a Cock ; or, Hippocampus Minor, 
 from its fimilarity to, and connection with, the l'ttbftance termed 
 Hippocampus Major. 
 
 In the fore-part of the bottom of the Lateral Ventricles, are 
 two large Eminences, called Corpora Striata, which become 
 gradually narrower, and recede from each other at their polferior 
 extremities. 
 
 The Structure of thefe is Cineritious externally, and mixed 
 with Medullary Striae within, fome of which form large Tranf- 
 verfe Medullary Arches, and others run more in a ftraight direc- 
 tion. 
 
 Between the pofterior parts of the Corpora Striata, arelituated 
 the Thalami Nervorum Opticorum, which have a roundifh form 
 and Medullary Surface, and are of a Striated appearance within, 
 bat the Striae are Id's dtftinft than in the Corpora Striata. 
 
16 
 
 Upon the Suiface of thefc Bodie', there are fmal! Eminences or 
 'Tubercles, fome of which are placed upon their fuperior, and 
 oihers upon their inferior extremities. 
 
 The inner parts of the Thalami are flat and contiguous, and 
 above they aie fo clofely conne&ed as to form one continued Sur- 
 face; called CommiJJura Mollis of the Optic Thalami. 
 
 The poflerior parts of the Thalami turn downwards and out- 
 waids, after which they aie elongated, to form the two white 
 Cords, called Traftus Optici. 
 
 In the Groove between the Corpora Striata and Thalami, there 
 is a Medullary Band on each fide, called Centrum Semicirculare 
 Gimihum oj V i e u s s li n s , or Tania Setnicircularis c/Haller, or 
 fimply Tcrnia. 
 
 Over the Thalami is placed the Choroid Plexus , — named from 
 its being compofed of a Chorus of Vefltls and Membranes. 
 It is a fine Vaf'cular Web, confining of fmall ramifications of 
 Aiteries and Veins, conin&ed by the Pia Mater, and ip read upon 
 the Surface of the Thalami. and fome of the adjacent parts. 
 
 The Choroid Plexus frequently contains numerous round 
 Globules, relembling Hydatids, which have been confidered by 
 fome Authors as Lymphatic Glands. 
 
 Under the Raphe of the Corpus Callofum, is placed the Septum 
 Lucidum, which, when viewed laterally, is obferved to be broad 
 before, curved at its edge, and to become gradually narrower to- 
 wards its polfer or extremity. 
 
 It is connected above to the Corpus Callofum, below to the 
 Fornix, and foims a d i ft i n 6b partition between the lateral Ventri- 
 cles. 
 
 It is formed of two Cineritious and Medullary Laminae, more 
 or lefs feparated from each other at their fore-part, by a fmall 
 Cavity, called Fiffure , or Fojja of Sylvius or Sinus of the Sep- 
 tum Lucidum, which, however, dees not communicate with the 
 Lateral Ventricles, though in feme fubjefts it reaches a confider- 
 able w.y backwards, and, as well as the other Cavities of the 
 Brain, has been found full of water in Hydrocephalous cafes. 
 
 Under the Septum Lucidum is placed the Subftar.ee which has 
 been. compared in fhape to a Vault by the Ancients, and from 
 that has obtained ihe name of Fornix. 
 
 The Fornix is merely a continuation of the Corpus Callofum, 
 and forms a fort of hollow Ceiling, with four Pillars called Cru- 
 ra, or Cornua, from then winding diieftion, of which there are 
 two anterior and two polienor. 
 
 The two /. interior Crura are fhort, run clofe together, and 
 become enlarged at their inferior parts. The two FoJIeiior Cru- 
 ra are long, ounfiderably diftam from each other, and form Cur- 
 vatures which correlpond with the couife of the Inferior Cornua 
 of the Lateral Ventricles. 
 
That part of the Crura Fornicis lying in the Inferior Cornua 
 of thefe Ventricles, forms thin borders, getting the name of Cor- 
 pora Fimbriata ; but, according to the Vic D’Azyr, they are 
 more properly termed Tcenia Hippocampi, from being united 
 with the great Hippocampus. 
 
 The body of the Forn x is narrow anteriorly, and becomes 
 conhderably broader behind, where it is incorporated with the 
 Corpus Callolum. 
 
 The under Surface of the pofterior part of the body of the For- 
 nix, is impreffed with numerous tranfverfe and oblique Line?* 
 which have been called FJalterium, or Lyra, from tome refem- 
 blar.ce they bear to the ancient mufical inftruments of thele 
 names. 
 
 The body of the Fornix is joined above to the Septum Luci- 
 dum ; below it is connected to the Thalami Optici by a Vafcu- 
 lar Membrane, called Tela Choroidea, which fpreads over the 
 Thalami, and unites the Choroid Plexus of the Lateral Ventri- 
 cles. 
 
 The Pedes Hippocampi, Great Hippocampus, ovCor- 
 NUA Ammonis, — named from a fuppofed relemblance to thefe 
 parts, — are two Medullary Eminences, which arife from thefides 
 of the pofterior exti emity ot the Corpus Callofum, and are lituated 
 in the inferior Prolongations of the Lateral Ventricles. 
 
 They run through the whole extent of the Prolongations, firft 
 behind, then at the outer part of the pofterior Pillars of the 
 Fornix, and are fo intimately connected witli them, that they 
 have been considered by fome Authors as forming part of the 
 Pillars thcmfelves. 
 
 They are final 1 at their origin, from which they continue to 
 mcreai'e to their farther extremity. 
 
 Like the greater pait of the Ventricles, they are covered exter- 
 nally with a Medullary Lamina; — internally they are found to 
 coniift of Medullary and Cineritious Laminae, of a convoluted 
 appearance. 
 
 At the inner edge of the Pedis Hippocampi, there is a plaited, 
 fer rated, or indented Margin, which, in the generality of (Quad- 
 rupeds, is much larger, in proportion to the fize of the Brain, 
 than it is in Man. — The refemblance, however, to the human 
 kind, in the ftructure of this particular part of the Brain, is 
 more finking in the Ape than in any other Quadruped. 
 
 In the bottom of the Lateral Ventricles, behind the anterior 
 Crura of the Fornix, and before the meeting of the Choroid 
 Plexufes of thele Ventricles, below the anterior part of the body 
 of the Torn ix, and over the fore-part of the third Ventricle, there 
 is a Hole, ot an oval form, by which the Lateral Ventricles 
 communicate freely with each other. See Monro’s Obf. on 
 Nerv. Syjl. 1783, and Treat if e on the Brain, 1797. 
 
 Vol. II. B 2 
 
IS 
 
 After dividing and turning back the Fornix, another commu- 
 nication from the above paffage is found, called Foramen Com- 
 mune Anterius, Vul-va, or Iter ad Infundibulum ; but properly. 
 Iter ad Tertium Ventriculum, or Paffage to the third 
 Ventricle. 
 
 Between the Commiffura Mollis of the Optic Thalami, and 
 Subftance callad Pineal Gland, there is a Imall paffage termed 
 Anus, or Foramen Commune Pojlerius, which has been l'uppofed 
 by fonie Authors to form a communication between the back-part 
 of the third Ventricle and Lateral Ventricles ; but it is complete- 
 ly fnut up by the Tela Choroidea, and alfo by the Fornix, which 
 adheres cloiely to tins Membrane. 
 
 The Third Ventricle is in form of a deep Fiffure, placed 
 between the inner ends ol the Thalami Optici, having the Com- 
 miffura Mollis of thele Thalami fi'uated above, the Crura Cere- 
 bri below, and the bodes of the Thalami on each fide. 
 
 The Infundieulum is a paffage of confiderable fize, of a 
 Cineritlous and Medullary ltru&ure, which leads downwards 
 and forwards, gradually eontrafting, and becoming folid at its 
 under end, where it terminates in the Glandula Pituitaria and 
 thus, contrary to the opinion of the Ancients, preventing the paf- 
 fage of any Pituitous Fluid from it to the Nofe. 
 
 The Glandula Pituitaria is of an oval form, about 
 the fize of a Field-Bean, lodged in the Sella Turcica, and fur- 
 jounded by a doubling of the Dura Mater. 
 
 On the outlide it is of a brownifh colour, being formed of Ci- 
 neritious Matter 5 it is whiter within, where it is mixed with 
 Medullary Subftance. 
 
 The Glandula Pituitaria was formerly fuppofed to abforb a 
 Fluid from the Infundibulum, and trjmfrnit it to the Nofe. It 
 has been already mentioned, however, that the Infundibulum is 
 impervious; and the real ufe of this Gland, as well as of the 
 other Tubercles of the Brain, feems ftill unknown. 
 
 At the fore-part of the third Ventricle, and immediately, be- 
 foie the Anterior Crura of the Fornix, there is a white Medul- 
 lary Cord, which runs tranfverfely through the Corpora Striata, 
 and has the name of Com mis sura Cerebri Anterior. 
 
 At the back-part of the third Ventricle, and under the root of 
 the Pineal Gland, there is another Cord fimilar to the former, 
 but fhorter, called Commissura Cerebri- Posterior. The 
 Comtmjjune Cerebri aflift in uniting the two ftdes of the Brain to 
 which they are fixed . 
 
 From the under and back-part of the third Ventricle, there is 
 a Paffage which leads to the fourth, under the name of Iter 
 ad Quart um Ventriculum, Canalis Medju{, or Aquaduc- 
 tus Sylvji. 
 
After the pofterior part of the Fornix, and theTela Cnoroidea 
 to which it adheres, have been removed, there ap: ear at the 
 back-part of the third Ventricle, behind the-Thalami, and over 
 the Iter a Tertio ad Quartum Ventriculuni, the Nates and Tes- 
 tes, or Tubercula Quadrigemin a, and Pineal Gland. 
 
 The Nates,ol' Tubercula Quadngemina Anterior a, are placed 
 uppermoft, and are of a rounder form titan the Testes, or Tuber- 
 ciila £>uadrige?nina Foderiora, — -which he immedia.ely below the 
 former. — Tite Teftes are broader from one iide to the other than 
 from top to bottom, and of a white colour. 
 
 A longitudinal Section Ihews the Tuoercula to be covered ex- 
 ternally with a thin Medullary Lamina, and to be Cineritious 
 within. 
 
 in Man they are more nearly of an equal lize than in Quad- 
 rupeds, as in the Ox, Sheep, &c. in which the Nates are large, 
 round, and of a brown colour, and the Teftes fmail and long. 
 
 Over the Nates, and under the back-part of the Fornix, is 
 placed a linall body, cf a Cinentious nature, about the lize of a 
 Garden-Pea, and of a Conoid, figure, called Glandula Pi- 
 ne alis, from its refemblance in fhape to a Pins or Fir Lons. 
 
 In confequence of being always prefent, and l’eldom found in 
 a dil’eafed tfate, it has been celebrated by Des Cartes, as be- 
 ing, according to his fuppolition, th s- Seat of the Soul. 
 
 The Pineal Gland is fixed at its root to the Comimffura Cere- 
 bri Pofterior, and fends out tnxo long Medullary Peduncles, or 
 Foot-Jlalks, to be fixed to the upper anti inner fide of the Thaiumi 
 and to the Anterior Crura of the Fornix. 
 
 Near, or in the Subftance of the Pineal Gland, fmail Calcare- 
 ous Concretions are fometimes found, called by Soemmering, 
 Acer<vulus Cerebri, from their being generally found colledled in 
 a heap. 
 
 They do not appear to be the effects of difeafe ; nor are they 
 met with till after the age of Puberty. 
 
 Cerebellum. 
 
 The Cerebellum is fituated in the Inferior FofTse of the Occi- 
 pital Bone, under the Pofterior Lobes of.the Brain, and is fepa- 
 rated from thefe Lobes by the Tentorium. 
 
 It is fomevvliat of a roundifli form, though a little broader from 
 one iide to the other than from before backwards. It is only 
 about a fifth or fixth part of the fize of the Cerebrum, and much 
 iimpler. 
 
 It is divided behind by the Falx Minor into two Lobes or He- 
 mifpheres, but lias no reparation above like the Brain. 
 
 Its Surface is divided into numerous Circumvolutions, which 
 from arches, decufl'ating each other in many parts, at (harp an- 
 
20 
 
 Tlie Cii'cumvolutions run chiefly in a Lateral direction, and 
 are formed of Laminae, with deep Sulci between them, into 
 which as in the Brayi, the Pia Mater infinuates itfelf, which 
 may be leadily leen by making a punilure into the Arachnoid 
 Coat, and blowing in air till it diltend the Cellular Subftance, 
 and leparate the Coats from each other. 
 
 It nas two middle Eminences, called Appendices Vermifor- 
 mes, from their relemblance to Earth Worms, one of which is 
 fituated anteriorly and fuperiorly, the other interiorly and pof- 
 teriorly. 
 
 Each of the Lobes of the Cerebellum is again divided into 
 Monticuli, or Lobules, which have different names according to 
 their relative lituations, cormtihons with other parts, &c. They 
 vary a little in the different Subjeits, but are befl ddUnguilhed 
 from the direction of their Convolutions. 
 
 The Subltance of the Cerebeilum confifts of Cineritious and. 
 Medullary Matter, as in the Ceiebrum ; but the Cineritious 
 bears a greater proportion to the Medullary in the former than in 
 the latter. 
 
 When the Ccrebellunj. is cut in a vertical direition, the Me- 
 dullary, part is then found to bear a linking relemblance 
 to the branching of the Ih ub called Arbor Vita, from which 
 circumftance it has obtained the name of.th's fhrub. 
 
 When cut in dices nearly parallel to the Baie of 'he Brain, the 
 Medullary Subilance appears in Laminae, coi refpontling to thole 
 of the Surface of the Cerebellum; and when cut to a conlidera- 
 ble depth, there is a Centrum MeduJlare uniting the Lateral Lobes 
 as in the Brain. 
 
 Between the Cerebellum; the under part of the Tuber Annu- 
 lare, and upper part of the Medulla Oblongata, the Fourth Ven- 
 tricle is fituated, which extends from the Eminences called t Teftes 
 to the posterior inferior Notch of the Cerebellum. 
 
 A little lower than the Teltes, the Ventricle becomes wider, 
 and forms an angle behind, from which again contrails, and 
 becoming narrower and pointed below like a writing-pen, is cal- 
 led Calamus Scriptorius . 
 
 Over the under end of the Aquteduihis Sylvii, and upper 
 part of the fourth Ventricle, there is a thin. Medullary Lami- 
 na, called Vabvula, but properly Velum Vieussknii. 
 
 At the Tides of the Velum Vieufl'enii there are two Medullary 
 trails, called Procejjus adFef.es, or Columns Vabvula: Vieus- 
 SEN1I. 
 
 The under end of the Ventricle is found to be (hut up by its 
 Choroid Plexus, which prevents any communication belweer 
 tins Cavity and that of the Spine. 
 
21 
 
 UNDER SURFACE OF THE BRAIN. 
 
 Near the middle of the Bafeof the Brain, and between its La- 
 teral Lobes, there are two l'mall, round, white bodies, termed 
 Emin entice Mammilai es, or Corpora Albicantia , Medullary 
 without, Cinerit.ous within, miitaken by lame Authors for 
 Glands. 
 
 In the Corpora Albicantia, various Medullary Strata termi- 
 nate, which come from different parts of the Brain. 
 
 Immediately before the Corpora Albicantia, two large white 
 Cords are obferved, called Crura, or Pedunculi Cerebri, or Cru- 
 ra Anteriora Medullas Oblongatcr, which arife from the Medul- 
 lary Sublfance of the Brain, and gradually approach each other 
 in their courfe, tjll they unite with the Tuber Annulare. 
 
 Their Surface is fiat, and compol'ed of diltinCt Medullary 
 Fibres ; internally they are compol'ed of a Mixture of CLneriti- 
 ous and Medullary Matter, the former of which being of a darker 
 colour at one par ticular part than in any other of the Brain, has 
 been ter med Locus Niger Crurum Cerebri. 
 
 Between the Crura Cerebri and Corpora Albicantia, there is a 
 Cineritious Sublfance, called Pons Tarjni, which joins thefe 
 two bodies of the oppofue lides together, and afillfs in forming 
 the bottom of the third Ventricle. 
 
 From the Medullar y part of the Cerebellum, which forms the 
 trunk of the Arbor Vitas two white cords arile, under the name 
 of Crura Cerebelli, or Crura Pcfrcriora, or Pedunculi Cerebetti, 
 which unite with the Crura Cerebri, to compote the Tuber An- 
 nulare, or Pons V arolii, l’o named from forming a Ring or 
 Bridge over the Crura. This ring is intimately incorporated 
 with, and formed by thefe Crura. 
 
 The Tuber Annulare is fituated over the back part of the body 
 of the Sphenoid and Cuneiform Procefs of the Occipital Bone. 
 Many tranlverfe Itreaks run on its Surface, and it is divided 
 into two lateral parts by a longitudinal depreffion, occafioned by 
 the fituation of the Vertebral Artery, 
 
 At the tore and back parts of the Tuber, are the Poratnina 
 Caeca Anterius et Pcjlerius, the former placed between the third, 
 and the latter between the lix h Pair of Nerves : Thefe two Fora- 
 mina penetrate only a little way at the edges of the Tuber, and 
 receive a Plexus of Veflcls, 
 
 In the Sublfance of the Tuber, there is much Cortical Matter, 
 which is formed inio Stria, running in different directions. 
 
 Continued from the luber, the.e is a large Sublfance in form 
 of an inverted Cone, which extends to the Foramen Magnum of 
 the Occipital Bone, under the name of Medulla Oblongata. 
 
 * Upon the Surface of the Medulla Oblongata, two iinall Emi- 
 nences appear, which run longitudinally and contiguous to each 
 
other and from their fltape have the name of Corpora Pyramida- 
 lia, or Eminently Pyramidales. 
 
 Between rhe Corpora Pyramidalia, there is a deep F Ifure, into 
 which the Pia Mater penetrates, and where Blood -v uld s pafs 
 into the interior part ot the Medulla. 
 
 At the outfide of the for met Eminences, are two others, !ome- 
 wbat of the form of Olives, (V. in which they arc termed Corpora 
 Oltvaria, or Eminently Olivares. 
 
 More externally than their, are two other Eminences, Iefs 
 evident than the former, which hive been defer died by iome Au- 
 thors by the name of Corpora Pyramidalia Lateralia. 
 
 The Medulla Oblongata is divided into two lateral portions, 
 by an anterior and polh rior Failure., and the two portions are 
 formed of Medullary Matter without, and a large proportion of 
 Cinei itious Matter internally, and joined together by Medullary 
 Fibres. 
 
 The Brain is the Grand and Primary Organ of Scnfe, with 
 which the Mind is fuppofed to be moft immediately and intimate- 
 ly connected, and from which the Nervous Influence is found, 
 by experiment, to be communicated to all the other parts of the 
 Body. 
 
 Origin of the Nerves. 
 
 The Nerves arife from the Medullary parts of the Brain, fome • 
 in fol d Cords, others in feparate Threads which afterwards unite 
 into Cords ; and have their name in numerical fucceflion, accord- 
 ing to their fituations, beginning anteriorly. 
 
 The Firf, or OlfaHory Pair of Nerves, arife from the back- 
 part of the pofterior lobes of the Brain, and run towards the Crifta 
 Galli of the Ethmoid Bone, over which each forms a brownilh- 
 coloured Bulb, from whence numerous fmall Nerves are lent 
 off. 
 
 The Second Pair, or Optic Nerves, are the continuations of 
 the Tbalami Optici. They are united immediately betore the 
 Infundibulum, and form an intimate intermixture of parts, and 
 again feparate previous to their palling into the Orbiis. 
 
 The ’Third Pair arife by numerous Threads, which are foon 
 collefted into Trunks. 
 
 The Fourth Pair, which are the fmalleft Nerves of the Body, 
 arife behind the Teltes, and have a long and winding courfe. 
 
 The Fifth Pair, which are the largeft Nerves in the Brain, 
 have each an anterior fmall, and a pofterior large Falciculus, 
 which arifes from the fide of the Tuber Annulare. 
 
 Tile Sixth Pair arife from the beginning of the Medulla Ob- 
 longata, where it joins the Tuber Annulare. Each of the Nen cs 
 of this Pair has a fmall Thread at its inner part. 
 
The Seventh Pair arife from the beginning of the lateral parts 
 of the Medullary Oblongata, and are divided on each fide intq a 
 Portia Mollis, afid Portio Dura. 
 
 The Eighth Pair arife by l'mall Fafciculi from the Corpora Oli- 
 varia. 
 
 The Ninth Pair of Nerves alfo arife by fmall Fafciculi, a lit- 
 tle below the former, from ihe Corpora P ramidalia. 
 
 The Origin of the Nerves will be defcribed at greater length, 
 in a fubfequent part of the Volume. 
 
 > 00000000 - 5 * 00000000 ' 
 
 OF THE EYE. 
 
 > 0 ' 
 
 The Eyes, which conftitute the Organ of Vifion, are fituated in 
 the Cavities of the Orbits, and are Unrounded by feveral parts, 
 fome of which proteft them fiorn injury, and others aflilf in the 
 peifoimance of their various motions. 
 
 The Orbits are formed of two Cones, fituated in the fore-part 
 of the Cranium, with their Apices behind, their Axes in an 
 horizontal fituation, and their Bafes turned obi queiy ou wards. 
 
 Each of the Orb ts is formed of different Procefi'es of the fol- 
 lowing Bones, viz. 
 
 Ttie upper part of each Orbit, by the Orbitar Plate of the 
 Frontal Bone; — the inferior, by the Orbitar Plates ot the fuperi- 
 or Alaxillary amt Malar Bones ; — the internal, chiefly by the 
 Orbit ir part of the Os Unguis and Pars Plana of the Ethmoid 
 Bone; — the external, by the Orbitar Piates of the Sphenoid and 
 Malar B nes ; — the pofterior, by the Sphenoid and Palate Bones; 
 — and the anterior edtre of the Or it, by the Frontal, luperior 
 Maxillary, and Mil tr Bones. 
 
 The Cavities of rite Orbits are l ned with Produ&ions of the 
 D nra Mater, whi.h pals out at the Foramina Optica and Lacera 
 and, at the anterior edges of the Orbits, join the Periotleum of 
 the Face, where they lupply the place of Ligaments to the Pal- 
 pebrse. 
 
 Supercilia. 
 
 The Supcrcilia, or Eye-B; ovjs, which are peculiar to the Hu- 
 man fpecies, are the arches of Hair iitu-ated upon the Supercilia- 
 
24 
 
 ry Ridges of the Frontal Bone. The Hairs are placed obliquely, 
 with their ro< ts towaids the Nofe, and the Arches elevated a lit- 
 tle above the reft of the Fore-head, by a considerable quantity of 
 Cellular Subftance lying under the Skin. 
 
 Theyaie moved in diffeient direft ons by the aflion of the 
 Frontal Corru ator, and Orbicular. s Palpebrarum Mufcles. 
 
 They are intended partly for ornament, and paitly as Shades 
 over the Eves, thereby preventing them from being injured by 
 extraneous Mattel, or by too great a quantity of light. They 
 alio aftlft in ex, i tiling the paflions of the Mind. 
 
 Palpebr^e- 
 
 The Palpebra, or Eye-lids, are chiefly compofed of a doubling 
 of the Skin, inch ding part of the Orbicularis Palpebrarum 
 Ivlufcle, and the Cartilages called Earfi, and forming angles at 
 the r ou er and inner extremities, termed Cantbi, or Corners of 
 the Eye. 
 
 The Upper Eye-lid 16 the one which moves principally in clo- 
 fing or opening the Eye, the under mut ing only when the Eye lids 
 are fhot with uncommon foi ce. 
 
 The motions of the Eye-lids are pei formed by the a£lion of the 
 Orb’cularis and Levitoi Palpebrarum Mufcles. 
 
 The Eve-lids fei ve as Curtains or Veil-, to defend the Eves 
 during lleep : They likewife p event them from being injured by 
 exti aneotis objefls, or by too much light. By their frequent 
 motion they increafe the lecreiion of the fears, apply them pro- 
 perly to the Surface of the Eye, and condufl what remains, after 
 wafhing the Eye, to the P'unfla Lacrymalia. 
 
 Tarsus. 
 
 This is a thin Cartilaginous Arch, fituated in the edee of each 
 Eye l : d, that in the upper one being confiderably broader than 
 the one below, and each broader at its middle than towards its 
 extremities. 
 
 Their edges are fo placed, that when the Eye-lids are fhut, a 
 groove is left next the Eye by which the Tears are conveyed to- 
 wards the Nofe. — They terminate at a little diltance front the in- 
 ner angle of the Eye. 
 
 They ferve to keep the Eyelids extended, allow them to be ac- 
 curately applied to each other, and prevent them from being col- 
 lected into folds. 
 
 Glandul.e Sebaceve, Ciliares, or MEIBOMI ANJE, — 
 the 1 all teim obtained from theii being defcribed by Meibomi- 
 us, — are placed between the Tat bus and lining of the Eye-lids, 
 an. I are formed of a feries of white lines or Follicles, running in 
 fei pentinc dueflions, which, when viewed through a magnifier, 
 nnpear like rows otaPearls, fiom which an Oily or Sebaceous 
 Matter, refembling little woims, may be readily fqueezed out 
 
25 
 
 through the Foramina or punfla Cilaria, placed upon the edges 
 of the Eve-lids. 
 
 The Matter of the Sebaceous Glands facilitates the motion of 
 the Eye lids, and prevents their accretion during fleep. 
 
 Cilia. 
 
 The Cilia, or Eye-lajhes, are (tiff Hairs placed in the edges of 
 the Eye-lids. Thole of the upper Eye-lid are bent upwards, and 
 are conliderably longer than thofe of the under Eye-lid, which 
 are bent in the oppulite direff on. In both Eye-lids, they are 
 awanting near the inner Angle. 
 
 The Cilia prevent dull, infeffs, &c. from getting into the 
 Eye, affilt in moderating the quantity of light fent into it, and 
 add to the beauty of the Face. 
 
 Glandula Lacrymalis. 
 
 The Glandula Lacrymalis, called, till of late years, the Glan- 
 dula Innominata Gai.eni, is ficuated upon the upper and outer 
 part of the Eye, in a hollow behind the outer end of the Superci- 
 liary Ridge of the Frontal Bone. — [t is a Gland of the Conglo- 
 merate kind, of a yellowifh colour, of an oblong form, and a 
 little flattened, with one end pointing to 'the Noi'e, the other to 
 the outer angle of the EVe. 
 
 Befides this, there is a chain of Smaller Glands, lying between: 
 thep.incipal Gland and upper Eye-lid, and connecting them to- 
 gether. 
 
 In the direflion of the Smaller Glands, there are feveral Ex- 
 cretory Duds, — delcribed by Dr. Monro, 1758, — which run 
 nearly parallel to, but do not communicate with each other. 
 
 The Excretory Duffs, on account of their fmallnefs, are not 
 often feen, and are difficult of injeffion. They terminate on the 
 inner fide of the upper Eye-lid, near the outer angle of the Eye, 
 and upper edge of theTarfus. 
 
 The ufe of this gland is to fecrete the Tears, which are fpread 
 over the Surface of the Eye by their own weight, and by the 
 motion of the Eye-lids, for the purpofe of preferving the delicacy 
 of the Eye, and particularly the tranfparency of the Cornea. 
 
 PUNCTA LACRYMALIA. 
 
 The Punfia Lacrymalia are two fmall Orifices placed near the 
 inner angle of the Eye, one in the upper, the other! in the under 
 Eye-lid, at the extremity of the Tarfus, and oppoiite to each 
 other. 
 
 Each Punflum is feated obliquely upon a fmall eminence, and 
 is furrounde l with a Cartilaginous Circle, which keeps it con- 
 ftantly open. 
 
 The Punfla Lacrymalia are the Orifices of two fmall Canals, 
 which run its the direflion of the edges of the Eye-lids towards 
 
 Vol. II. C 
 
26 
 
 the fide of the Nofe, where they approach each other, and termi- 
 nate together in the Lacrymal Sac. 
 
 The Tears which remain after moiftening the Eye are abforbed 
 by the PunCla, after the manner of Capillary attraction, and are 
 conveyed through their Duds into the Lacrymal Sac by the im- 
 pulfe of the Eye- lids. 
 
 Cahuncula Lacrymalis. 
 
 The Caruncula Lacrymalis is a fmall Gland of a reddifh colour, 
 of the Conglomarate kind, fituated between the inner angle of 
 the Eye-lids and Bali of the Eye, which fupplies Sebaceous 
 Matter to this part of the Eye-lids, and ferves in particular to 
 Separate the PunCla Lacrymalia, and to direft the Tears to them 
 while the Eye-lids are fhut. 
 
 Minute Hairs are found upon the Surface of this body, ferving 
 to entangle fmall objeCls which get into the Eye. 
 
 Valvula Semilunaris. 
 
 The Valvula Semilunaris is a fmall doubling of the Tunica 
 ConjunCliva, which lies between the Caruncula Lacrymalis and 
 Ball of the Eye. 
 
 It is larger in the Ape and other Quadrupeds than in the Hu- 
 man fpecies, and (fill larger in Birds, in which, as well as in 
 Quadrupeds, it is called Membrana NiHitans. 
 
 It is in form of a Crefcent, the horns of which are turned to- 
 wards the PunCla Lacrymalia, and aflifls the Caruncula in con- 
 ducting the Tears to the PunCla. 
 
 THE BALL OF THE EYE. 
 
 The Ball, Globe, or Bulb of the Eye, is of a fphevical form, to 
 colled the rays of light into a proper Focus, and is furrounded 
 behind by a quantity of foft Fat, to allow the Eye and its Muf- 
 cles to move with facility. 
 
 The Ballot the Eye is compofed of Coats, Humours, Veffels, 
 and Nerves, to be next defcribed. 
 
 COATS. 
 
 Tunica Adnata. 
 
 The Tunica Adnata, or ConjunEliva, named from its connec- 
 ting the Eye to the Orbit, is a reflection of the Skin continued 
 from the Eye-lids over the whole fore-part of the Ball of the 
 Eye. 
 
 It adhere B flightly by means of Cellular Subftance to the 
 White of the Eye, but fo firmly to the Cornea, as to be feparated 
 from it with difficulty. 
 
 It is fo remarkably thin, that the colour of the fubjacent parts 
 fhine readily through it. 
 
 Between this Coat and the white part of the Eye, there is a 
 quantity of loofe Cellular Subftance, which is very Vafcular, 
 and is the common feat of Ophthalmia. 
 
27 
 
 The Tunica Adnata fup ports the Ball of the Eye, prevents 
 extraneous bodies from getting to the back-part of it, and forms- 
 a l'mooth covering to leflen the friction between the Eye and Eye- 
 lids. 
 
 Cornea. 
 
 The Cornea, fo called from its refemblance to Horn, is termed 
 by many Authors Cornea Lucida, to diilinguifh it from the Scle- 
 rotica, named Cornea Opaca. 
 
 It forms the anterior Pellucid Covering of the Eye, is more 
 convex than the reft of the Ball, and is joined to the Tunica 
 Sclerotica, like the Segment_of al'mall Sphere to that of a lar- 
 ger one. The convexity, however, varies in different perlons, 
 Jo as to form a fliort or long lighted Eye, according as the Cor- 
 nea is more or lei’s prominent. 
 
 Ill a recent fubjeft, it is hard, denfe, and tranfparent ; but 
 after maceration in water, it becomes loft and opaque, and may 
 be readily feparated, efpecially in voting Animals, into differ- 
 ent Lamellae, the anterior of which is the continuation of the 
 Tunica Adnata. 
 
 By a (light degree of putrefaction, it may alfo be feparated 
 from the Tunica Sclerotica. 
 
 In the Whale, the edge of the Cornea is received into a diftinCl 
 Groove-formed by the Sclerotica. 
 
 In a found ftate, it has no Veflels which carry red Blood, 
 though fucli are frequently feen on it when the Eye is inflamed. 
 
 Its nerves are too frnall to be traced; yet it poffefl'es exquifite 
 fenfibility. 
 
 It collects the rays of light, and tranfmits them to the Eye, 
 protects the tender parts within it, and contains the Aqueous 
 Humour. 
 
 Iris. 
 
 The Iris, which is named from being in fome perfons of dif- 
 ferent colours, is the only Coat which poffefl'es motion. It was 
 conlidered as a continuation of the Choroid Coat, until defcribed 
 by Zinn, who (hews that it is only connected to this Coat byt- 
 the medium of the Ciliary Circle. 
 
 It is placed at a little diftance from the Cornea, begins a f ilia'll 
 way behind the j unCtion of that Coat with the Sclerotica, and 
 running acrofs, it forms a Septum, a little convex anteriorly, 
 and perforated in the middle by a Hole, called the Pupil, or 
 fight of the Eye. 
 
 The term Pupil is applied, becaufe it reprefents objeCts no lar- 
 ger than a Papilla or Puppet. 
 
 In the Foetus, the Pupil is cove: ed with a Vafcnlar Membrane, 
 termed Membrana Pupillaris, which generally dil’appears between 
 the feventh and ninth month of geftation. 
 
28 
 
 Upon the back-part of the Iris, there is a dark-coloured Pig- 
 ment, confidered by the Ancients as a pofferior Layer of the 
 Iris, called by them Uvea, from its refemblance in colour to 
 the Grape. 
 
 When the Paint is wafiied off, the Iiis exhibits two fets of 
 Fibres,— concerning which Authors have entertained various 
 opinions, — one in the form of Radii, the different colours of 
 which give the diverfity of colour to the Eye ; the other circular, 
 and furrounding the inner edge of the Iris, an'd confidered by, « 
 Dr. Monro as the Sphinfter Mufcle of the Pupil. 
 
 The Iris has alfo many Blood-vtffels, which can be readily 
 injefled ; and has a greater proportion of Nerves than almoft any 
 other part of the Body. 
 
 It floats in the Aqu-tous Humour, and is of fuch a nature, 
 that upon expolure to a ftrong light, or when the Eye looks upon 
 a near objeft, the diameter of the Pupil is diminifhed; and vice 
 verfa. 
 
 The different motions of the Iris are fuppofed to be excited by 
 the fenfibility of the Retina, and the quantity of light falling 
 upon that Nerve. 
 
 The Iris ferves to regulate the quantity of light fent to the 
 bottom of the Eye. 
 
 Tunica Sclerotica. 
 
 The Tunica Sclerotica, which is named from its hardnefs, is 
 the largeft and ftrongeff Coat of the Eye, covering the whole 
 Ball, excepting the parts occupied by the entrance of the Optic 
 Nerve behind, and by the Cornea before. 
 
 It is fo firmly fixed to the edge of the Cornea, as to have been 
 confidered by many Anatomills as a continuation of the fame 
 fubitance; but it differs from the Cornea in the following parti- 
 culars ; it is of a pure white colour, is formed of Fibres running 
 in every direction, and clofely interwoven with each other, is 
 not divifible into Layers, and may be fepafated from it by art, 
 as has been already mentioned. 
 
 It is thickeit pofter'orly, and receives a little tinge on the 
 inner Surface, from the Choroid Coat, with which it is in con- 
 ta£l. 
 
 It gives form and ftrength to the Eye, and fupports the tender ' 
 parts within it. 
 
 The Tendons of the four Recli Mufcles of the Eye are fixed 
 to the fore-part ot the Tunica Sclerotica ; and thefe, or the Cel- 
 lular Vaginae covering them, have been fuppofed to give an ad- 
 d tional whitenefs to the Eye ; and the part giving this whitenefs 
 lias been termed Tunica Albuginea But the Sclerotic Coat is 
 every where of a pure white, and can receive little additional 
 brighmefs from any fuch coverings. 
 
29 
 
 Tunica Choroides. 
 
 This Coat derives its name from the Veffels with which it 
 abounds, forming a Chorus ; or from its fuppofed refemb lance 
 to the Membrane called Chorion , which furrounds the Fcctus in 
 Utero. 
 
 The Choroides lies under the Sclerotica, and is connected to it 
 by the Trunks of Veffels and Nerves which pals from the one 
 Coat to the other, and all’o by a tender Cellular Subftance, or a 
 brown colour, with which the inner Surface of the Sclerotica is 
 tinged. 
 
 It begins at the entrance of the Optic Nerve into the Eye, runs 
 between the Sclerotica and Retina, nearly to the Cry ftal line 
 Lens, where it is more firmly connefted to the bclerotic Coat 
 than it is elfewiiere, by means of the Ciliary Circle. 
 
 The Ciliary Circle, or Ciliary Ligament it is called, is com- 
 posed of a quantity of condenfed filming Cellular Subftance, which 
 forms a white Ring connecting the fore-part of the Choroides, 
 and the root or outer Margin. of the Iris, to the Sclerotica. 
 
 The Choroid Coat is much thinner and more tender than the 
 Sclerotic, and is one of the moft Vafcuiar parts of the Body, 
 leeming at firft fight to be entirely compofed of Veffels. — The 
 greater number of thofe on the outiide run in whirls ; while thole 
 on the inlide, running nearly parallel to each other, gave rife to 
 the fuppoled exiltence of the Membraua Ruyfchiana. 
 
 It is alfo furnilhed with numerous Nerves, which are united 
 with its Veffels by a fine Cellular Texture. 
 
 In the human Eye, the Choroides is of a dufky brown colour, 
 both externally and internally ; out the colour varies confideva- 
 biy in the eyes of different animals- 
 
 The inner Surface of this Coat, which is Villous, was defcrib- 
 ed byRuyscH as a diflinSi Lamina, and has been termed by 
 many Anatomifts Tunica Ruyfchiana ; — Haller however, and 
 Zinn, and many others who followed them, have demonftrated 
 this Coat to. conlift of only one Lamina ; though in Sheep, 
 and n l'orue other animals, it appears to be double. 
 
 Upon the inner tide of the Choroides, there is a dark-coloured 
 Mucus, called Pig/nentum Nigrum , — fuppofed to be produ ed 
 from the Veffels of this Coat, — which is blackeft and t'nickeft at 
 the fore part of the Eye, where it adheres l'o tenacioufly as io be 
 removed with difficulty ; bur behind it is thinner, more fluid, 
 and more eaiily removed; becoming gradually lefs evident, and 
 almolt difappearing round the Optic Nerve. 
 
 In advanced age, the Pigmentum Nigrum becomes more di- 
 luted, and of a lighter colour ; lb that the Veffels of the Cho- 
 roid Cuat may be l'een fhining through the Vitier.us H • • 
 
 You II. C 2 h ' 
 
30 
 
 Though Haller, denies that the Membrana Ruyfchiana can 
 ever be leparated, in the Human Eye, fiom the Choroides,— he 
 retains the name, to denote the black Surface of this Coat. 
 
 In grameniverous animals, in fifhes, and in thofe animals 
 which go in quell of prey in the night, the Paint is of a light and 
 /hining colour in the bottom of the Eye, and is called Tapetum . — 
 In an entirely white Rabbit, the Paint is awanting, and the Eye 
 has a red colour from the Velfels of the Choroid Coat ; but the 
 rednefs difappears when the animal is dead. 
 
 At the fore-part of the Choroid Coat, and oppofite to the Cili- 
 ary Circle, there is a black radiated Ring, called Corpus Ciliare, 
 which is about the fixth part of an inch in breadth towards the 
 Temple, but fomewhat narrower towards the Nofe. 
 
 In the pofterior portion of the Corpus Ciliare, there are nu- 
 merous pale radiated Ciliary Stria, but fo covered with the Pig- 
 menium Nigrum, as not to be diftinftly feen till the Paint is re- 
 moved. 
 
 Near the connection of the Corpus Ciliare with the root of the 
 Iris, t'nefe Striae become gradually broader and more elevated, and 
 form about feventy white Plica or Folds, termed ProceJJus Ciliares, 
 the intervals of which are alfo covered with Pigmentum Ni- 
 grum. 
 
 The ProceJJus Ciliares, which obtain their name from their re- 
 femblance to the Cilia of the Eye-lids, are commonly formed each 
 of two or more Striae, are not all of an equal fize, and many of 
 them forked at their extremities. 
 
 The Corpus Ciliare, formed of the Ciliary Strias and Ciliary 
 Procefies, has no appearance of Mufcularity, though the contrary 
 has been fuppofed by fome Authors. A fine Injection (hew; it 
 to be chiefly formed of a continuation of the Blood-veflels of the 
 Choroid coat, the branches of which divideinto fuch minute parts, 
 ■as to give the whole a Viilous appearance. 
 
 The Corpus Ciliare is glued to the Retina, at the fore-part of 
 the Vitreous Humour, .aiid a little behind the edge of the Cry- 
 ftalline Lens ; but the Ciliary Procefies float in the Aqueous Hu- 
 mour in the pofterior chamber of the Eye, at tile inner fide of the 
 root of the Iris, and may be readily turned back behind the edge 
 of the Lens, to which they are contiguous, but do not adhere. 
 
 The Choroid Coat, with its dark Paint, ferves to fuffocate the 
 rays of light which pals through the Retina, and thereby to al- 
 low a diftm£t image to be formed upon the bottom of the Eye, and 
 to prevent the rays from being refle&ed fo as to form a fecond 
 image. 
 
 In thefe animals in which this Coat or its Paint is of a bright 
 colour, it a6ls as a mirror to refleft light, and make the impreflion 
 ftronger. 
 
31 
 
 Optic Nerve and Retina, 
 
 The Optic Nerve, in its pafiage through the Orbit, is cover- 
 ed by a continuation of" the Membranes which furround the 
 Brain. 
 
 At the Foramen Opticum, the Dura Mater is divided into 
 two Lamina ?, one of which affifts in forming the Periofteum of 
 the Orbit; the other, which is again divided into two Laminae, 
 furnifhes a Iheath to the Nerve, and accompanies it to the Tuni- 
 ca Sclerotica, to which it is fo firmly connected by Cellular Sub- 
 ftance, as to have induced fome Authors to defcribe the Sclero- 
 tica as a continuation of the Dura Mater. 
 
 The Body of the Nerve is ftill more clofely inverted by the 
 Pia Mater, which alfo forms (heaths round the Nervous Fafci- 
 culi, and accompanies the Nerve into the Eye. 
 
 At the back-part of the Ball of the Eye, and a little removed 
 from the Axis, towards the Nol'e, the Fafciculi of the Optic 
 Nerve pals through a Cribriform part of the Sclerotic Coat. 
 
 The Nerve is contracted at its entrance through the Sclerotic 
 Coat, but immediately after its ingrefs, it expands to form the 
 Retina, — fo called from its fuppofed Reticular appearance. 
 
 In the middle of the entrance of the Optic Nerve, the Artery 
 is l'een dividing into branches, which are difperfed upon the in- 
 ner Surface of the Retina. 
 
 The Retina advances between the Choroid Coat and Capfule 
 of the Vitreous Humour, to the fore-part of the Eye, and ter- 
 minates ordifappears upon the anterior part of the edge, or great- 
 ell diameter of the Capfule of the Cryrtalline Lens. 
 
 The Retina is contiguous to the Choroid Coat and Capfule of 
 the Vitreous Humour, but does not adhere to either, by Blood- 
 vSfiels or otherwife, till it reach the Corpus Ciliare. 
 
 Under the Corpus Ciliare, the Retina is fo covered externally, 
 with the Pigmentum Nigrum, and adheres internally fo clofely 
 to the Capfule of the Vitreous Humour, as to be prevented from 
 being l'een till the black Paint be waflied off, or till all the Coats 
 be removed pofteriorly, and the Eye viewed through the medium 
 of the Vitreous Humour. 
 
 The Retina is compoled of a tender and Pulpy-like Subftance, 
 is femi-tranfparent, and of a light-grey colour, refembling that 
 of gi ound glafs. 
 
 From the entrance of the Optic Nerve, to the edge of the Cor- 
 pus Ciliare, the Retina is of an equal and uniform Subrtance, 
 and is foeafily torn and feparated from the edge of that body, as 
 to be defcribed by many Authors as terminating there. 
 
 _ Under the Striae and Procertes of the Corpus Ciliare, the Re- 
 tina is thinner than in the pofterior part of the Eye, and is fo im- 
 
32 
 
 preffed by thefe bodies, as alfo to have the appearance of Str'x, 
 which terminate in numerous minute Fibres, like Nerves in 
 other parts ol the Body. 
 
 The Retina is the feat of Vifion, and therefore the primary 
 part of the Eye, to which all the other parts within the Orbit are 
 l'ubfervient. 
 
 HUMOURS. 
 
 Aqueous Humour. 
 
 The Aqueous Humour is lodged in the fpace between the Cor- 
 nea and Cryftalline Lens. 
 
 This fpace is divided into two Cavities, called Chambers, the 
 anterior of which is fituated between the Cornea and Iris, and is 
 the larger of the two. 
 
 The pofterior is placed between the Iris and Cryftalline Lens, 
 and is fo much fmaller than the former, that its exiftence has 
 been denied by fome Authors, though it is a diftin<5l Cavity, de- 
 monftrable, not only in the Adult, where the Pupil is open, but 
 in the Foetus before the Pupil is formed. 
 
 The Aqueous Humour is clear as the pureft Water, but is 
 fomewhat heavier, poflefles a fmall degree of vifcidity, contains 
 a little Salt, and is about five grains in weight. 
 
 In the Foetus, and for the firft month after birth, it is reddifh 
 and turbid. 
 
 When evacuated, it is quickly renewed ; for within forty- 
 eight hours after it has been let out by a punflure, the Cornea is 
 obferved to be again perfectly diftended. 
 
 It is fuppofed to be fecreted from the neighbouring Arteries, 
 particularly from thofe on the fore-part of the Iris and Ciliary 
 Proceftes. 
 
 It lerves to keep the Cornea diftended, and, by its roundifh 
 form and pell ucidity, it colledls and tranfmits the rays of light 
 to the inner parts of the Eye. It likewife guards the Iris and 
 Lens, and admits of the motions of the former. 
 
 Crystalline Lens. 
 
 The Cryjfallbie Lens, which has its name from its refemblance 
 to Cryftal, and from its Lenticular form, — though a folid body, 
 which may be moulded into various fhapes, — has always been 
 claflVd among the Humours of the Eye. 
 
 It is fituated behind the Aqueous Humour, oppofite to the 
 Pupil, and the whole of its pofterior part is received into a de- 
 preflion on the fore-part of the Vbreous Humour. 
 
 L ke a common Lens, or magnifying Glafs, it has two convex 
 Surfaces, the anterior of which is in general lefs convex than the 
 pofterior, the two being formed of fegments of fpheres of an un- 
 equal fize. 
 
OJ 
 
 The anterior Surface, according to the experiments of Petit, 
 forms the fegment of a fphere, the diameter of which is between 
 feven or eight lines, or twelfths of an inch; while the pofterior 
 Surface is only equal to the fegment of a fphere of about five lines 
 in diameter. 
 
 It has been obferved by Zinn, — that the figure of the Lens 
 varies at different periods, being in the Foetus almotl of a Ipheri- 
 cal form, but becoming gradually flatter on the anterior and pof- 
 terior Surfaces, till about the age of thirty, after which its form 
 does not appear to vary. 
 
 As the figure, fo alfo the colour and confiftency are found to 
 change at different times of life.— In the Foetus, not only the 
 Capfule, but the Lens alfo is of a reddifh colour ; but, imme- 
 diately after birth, they become perfeffly tranfparent. — In a per- 
 fon confiderably advanced in years,' the Lens is obferved to ac- 
 quire a certain degree of yellownefs, which appears fii If in the 
 centre, and afterwards extends gradually to the circumference ; 
 and in extreme old age, this yellow tinge becomes lo deep as to 
 referable Amber. 
 
 An Aqueous Fluid is deferibed as being fituated between the 
 Cryftalline Lamellae, which is fuppofed to decreafe in quantity, 
 and to become yellowiflr, the Lens at the fame time increafing in 
 folidity as the perfon advances in life. — This difference however, 
 of convexity, colour, and confidence, according to the difference 
 of age, is not uniformly met with. 
 
 The Lens becomes opaque foon after death, and acquires a a 
 additional opacity when put into fpirit of wine. 
 
 It is compofed of concentric Lamellae, laid over each other 
 like the coats of an Onion. Thele Lamellae are connefiled by a 
 fine Cellular Subftance, and are more clofely compacted the near- 
 er they are to the centre. ‘ 
 
 This lamellated ftru&ure may be' readily obferved in the Eye 
 of an Ox, or any other large animal, but is moft evident when the 
 Lens has been macerated in Water or Vinegar. 
 
 When the maceration is continued for fome time, the Lamel- 
 lae put on a radiated appearance, the Radii running in a vertical 
 manner, or iffuing from the centre to the circumference, dividing 
 the Surface into Ifofcular Triangles. 
 
 The Lamellae were difeovered by Leuwenhoeck, to be of a 
 Fibrous ftrufture. By a late writer, thefe Fibres have been con- 
 fidered as Mufcular, — but this opinion of the Mufcularity of the 
 Lens, feems to have gained very few profelytes. 
 
 The fubftance of the Lens fomewhat refembles half-melted 
 Gum, is very foft and tender on the outfide, but becomes gra- 
 dually firmer and tougher towards the centre, where it forms 3 
 N ucleus . 
 
 The Lens is furrounded by a very pellucid proper Capfule, 
 called Tunica Aranea, or CrjJiallina, which is much thicker and 
 
34 
 
 more elaftic tlian the Capfule of the Vitreous Humour, but ad- 
 heres fo flightly, and is fo eafily lacerated, that after a fmall 
 punfture is made in it, the Lens ftarts out, upon applying gen- 
 tle prefiTure to the Capfule. 
 
 The pofterior part of the Capfule is much thinner, fofter, and 
 ■weaker than the anterior ; but is quite a diJUnfl Membrane from 
 the Tunica Vitrea ; yet fo firmly connected to it by Cellular Sub- 
 fiance, that it is difficult to feparate them without lacerating both 
 the Vitreous Coat and its Humour. 
 
 Some Authors defcribe an Aqueous Humour as feated between 
 the Lens and its Capfule; while others, of no fmall refpeflabili- 
 ty, deny the exiftence of this Humour, as well as of that which 
 is faid to be tituated between the Lamella? of the Lens. 
 
 The VeJJ'els of the Lens are not to be feen in the Eye of an 
 Adult ; but in that of a Foetus, Petit found Vefl'els palling 
 from the Corpus Ciliare, over the fore-part of the Capfule of the 
 Lens. 
 
 Winslow afterwards obferved, that in the Foetus, and in new- 
 born children, a fine injeftion fucceeded fo well as to difcover the : 
 Vef.'els of the Membrana Cryftalina and Vitrea ; — and in a Foe- 
 tus of about fix months, the injected liquor feemed to him to have 
 penetrated a part of the Cryftalline and Vitreous Humours. 
 
 Albinus derives thefe veffels from a double fource.— In the 
 Eye of a Whale, he demonftrated Veffels palling from the Cilia- 
 ry Procefi'es to the Subftance of the Lens ; — and, at a later peri- 
 od, he injetted in the human Eye, a fmall bianch arifing from 
 the Central Artery of the Retina, which proceeded in a ftraight 
 direction through the Vitreous Humour, and divided in the pofte- 
 riorpart of the Capfule into numerous branches, many twigs of 
 which plunged into the Subftance of the Lens. 
 
 This artery and its branches have been frequently and fuccefs- 
 fully injefied by fucceeding Anatomifts. 
 
 Vitreous Humour. 
 
 The Vitreous Humour, fo called from its refemblance to melted 
 Glafs, is fituated in the back-part of the Cavity of the Eye, which 
 it occupies from the infection of the Optic Nerve to the Surface of 
 the Cryftaline Lens. 
 
 It is round at the back-part and fides, where it is covered by 
 the Retina, but is concave before, where it forms a bed for the. 
 Cryftalline Lens. 
 
 It is by much the largeft of the three Humours, occupying 
 upwards of nine-tenths of the whole Eye, and has a Gelatinous 
 appearance, — or is fomewhat like the glaire of an Egg. 
 
 In an Adult it is always very tranl'parent, and in an Old Per- 
 fon it does not like the Lens, degenerate into a yellow, or any 
 other colour. 
 
oo 
 
 In the Fcetus, like the Aqueous Humour, it is of a reddifh 
 colour. 
 
 The liquor with which the Vitreous Humour, is filled, is 
 fimilar to the Aqueous, — very fluid, tranfpires readily through 
 theCapfule, thou/h that Coat be entire, and, like the Aqueous 
 Humour, is fomewhat thicker, heavier, and more vifcid than 
 Water. 
 
 When this Humour is evacuated by punffure, in the living Bo- 
 dy, it is very feldom, though fometimes renewed. 
 
 Upon the Surface of this Humour there is a Coat, termed Vi- 
 trea, as tranfparent as the Humour itfelf, and fo thin and Cob- 
 web-like, as to have the name of Aranea. 
 
 The Tunica Vitrea is remarkably fmooth on its outer Surface; 
 but within it fends Procefies into the body of the Humour. 
 
 Some Authors, and among thefe Winslow, have defcribed 
 this Coat as confiding of two Laminae, but Sabatier, and 
 other late writers, feem fufficiently fatisfied that it is a Angle 
 Layer ; and even this fingle Layer cannot be railed but with dif- 
 ficulty, though it is demonftrable by making a punfture to allow 
 the Humour to efcape, and by afterwards dillending the part with 
 air. 
 
 The ftrufture of the humour confifts in a fet of delicate Cells, 
 which contain the liquor within them, as may be feen by the 
 afliflance of Acids, or by boiling Water, or by Congelation. 
 
 The Cells of the Humour communicate freely with each other, 
 as appears from the liquor oozing out by the fmallefl: pundlure 
 made in the general Capfule. 
 
 Under the Corpus Ciliare, the Capfule of the Vitreous Hu- 
 mour fends off an external Lamina, which accompanies the Re- 
 tina, and is inferted with it into the fore-part of the Capfule of 
 the Lens, a little before its anterior edge. It is termed Mem- 
 branula Corona: Ciliaris, or Zomula Ciliaris, from its Striated 
 appearance and Circular form, and aflifts in fixing the Lens to 
 the Vitreous humour. 
 
 After fending off the Ciliary Zone, the Coat of the Vitreous 
 Humour goes behind the Capfule of the Lens, to which it firmly 
 adheres. 
 
 Between the Ciliary Zone and part where the Capfule of the 
 Vitreous Humour adheres to that of the Lens, — which is at the 
 fame diftance behind the edge of the Lens with the diftance of the 
 infection of the Ciliary Zone before it, — a Paflage is formed, na- 
 med Canalis P etitianus , after Petit, who difcovered it. 
 
 The Membranes forming this Paflage are pervaded by tranf- 
 verfe Fibres, in fuch a manner, that when air is introduced, it 
 goes freely round the edge of the Lens; but the Paflage has a 
 Cellular appearance, being contra&ed and dilated alternately. 
 
36 
 
 The Canal of Petit is nearly of the fame breadth with the 
 Corpus Ciliare, is always empty and has no communication with 
 the Capfules of the Vitreous or Cryftalline Humours. 
 
 Nu Vefiels are to be feen in the Vitreous Humour of an Adult, 
 but in the Eye of a Foetus, an artery is ol-ferved to arife from 
 the central one of the Retina, which pafl'es through the middle of 
 the Vitreous Humour, fending twigs to the Cellular Texture of 
 this Humour while the principal Trunk is continued to the Cap- 
 fule of the Cryftalline Lens, as has been aheady obferved. 
 
 The Vitreous Humour ferves to give fhape to the Eye, to keep 
 the Coats properly expanded, to preferve the due diftance of the 
 Lens, and direff the rays of light to the Retina. 
 
 MUSCLES OF THE BALL OF THE EYE. 
 
 The Ball of the Eye is moved by fix Mufcles, which are divi- 
 ded, on account of their d'reftion, into Jour Jlraight and tnxio 
 oblique Mufcles, obtaining their refpective names from their fize, 
 fituation, dire&ion, or ufe. 
 
 Of the ftiaight Mufcles, one is fituated above the Eye, ano- 
 ther below it, and one on each fide. Of the oblique, one is placed 
 at the upper and inner, and the other at the under and cuter part 
 of the Eye. 
 
 The Rebli Mufcles are not ftraight, as the name implies ; for, 
 on account of the fituation of the Eye and fhape of the Orbit, the 
 internal, or that next the Nofe, is the only one which funs in a 
 ftraight direflion. 
 
 Neither are they all equally long, the internal being the fliort- 
 eft, the external the longeft, and the other two nearly of the fame 
 length. 
 
 The four ftraight Mufcles, which bear a ftrong refemblance to 
 each oilier, arife by a narrow beginning, a little Tendinous and 
 Flefhy, from the edge of the Foramen Opticum, where they em- 
 brace the Optic Neive at its entrance into the Orbit. 
 
 In their palfage foi wtirds, they form Flefhy Bellies, which 
 fend off broad and very thin Tendons, to be inferted into the 
 Sclerotic Coat, under the Tunica Adnata, about a quarter of an 
 inch behind the edge of the Cornea, and at equal diftances from 
 each other. 
 
 At the place of their infertion they arc fo intimately connefted 
 wilh the Sclerotica, that they cannot be feparated from it, or be 
 brought as far as the Cornea, without evident laceration. 
 
 The different Mufcles of the Ball, of the Eye, where they lie 
 upon the Ball, are covered with a Cellular Sheath, which after- 
 wards degenerates into that Cellular Subftance which is interpo- 
 fed between the Sclerotica and Conjun&iva. 
 
37 
 
 Levator Oculi ; 
 
 Or ReBus Attollens, or Superbus. 
 
 Origin : From the upper part of the Foramen Opticum, below 
 the Levator Palpebrae Superioris. 
 
 Infertion: Into the upper and fore-part of the Tunica Sclero- 
 tica. 
 
 Afiion ; To raife the fore-part of the Ball of the Eye. 
 
 Depressor Oculi ; 
 
 Or Refills Deprimens, or Humilis. 
 
 Origin : From the inferior part of the Foramen Opticum. 
 
 Infertion : Opp*fite to the former. 
 
 Afiion : To pull the fore-part of the Eye downwards. . 
 
 Adductor Oculi; 
 
 Or Refius Adducens, or Bibhorius. 
 
 Origin : From the Foramen Opticum, between the Obliquus 
 Superior and Depreffor. 
 
 Infertion : Oppoiite to the inner angle. 
 
 Afiion: To turn the fore-part of the Eye towards theNofc. 
 
 Abductor Oculi; 
 
 Or Refius Abducens, or Indignabundus . 
 
 Origin : From the Bony Partition between the Foramen Opti- 
 cum and Lacerum. 
 
 Infertion: Into the Ball of the Eye, oppoiite to the outer 
 Angle. 
 
 Afiion : To turn the fore-part of the Eye towards the Temple. 
 
 When two of the oppoiite Refli Mufcles, or all of them aft 
 together, they draw the Eye into the Orbit. 
 
 When two of the adjacent Refti Mufcles aft, they turn the 
 fore-part of the Eye obliquely in a direftion towards their Ori- 
 gins. 
 
 Obliquus Superior; 
 
 Or Obliquus Major, or Trochlearis. 
 
 Origin : Like the ftraight Mufcles, from the edge of the Fo- 
 ramen Opticum, between the Levator and Adductor Ocuii. 
 From thence it runs ftraight forward, fends off a long round Ten- 
 don, which paftes through a Cartilaginous Pulley fixed behind 
 the Internal Angular Procefs of the Os Frontis: from this it 
 runs a little downwards, and returns backwards and outwards, 
 palling under the Levator Oculi, to have its 
 
 Inj'ertion : By a Broad thin Tendon, into the Tunica Sclerotica, 
 about half-way between the infertion of the Levator Oculi and 
 entrance of the Optic Nerve. 
 
 Afiion: To roll the Ball of the Eye, by turning the Pupil 
 downwards and outvvards. 
 
 Vol. II. D 
 
58 
 
 Obliquus Inferior.; 
 
 Or Obliquus Minor. 
 
 Origin: By a narrow beginning, from the anterior edge of the 
 Orbitary Procefs of the Superior Maxillary Bone, near the La- 
 crymal Groove, from which it palfes obliquely outwards, back- 
 wards and itpwaids, round the Ball of the Eye. 
 
 lnfertion : By a broad thin Tendon, into the Sclerotic Coat, 
 between the entrance of the Optic Nerve and infertion of the Ab- 
 duftor Oculi, and oppofite to the intention of the Superior Ob- 
 lique Mufcle. 
 
 ABion : To roll the Ball of the Eye, by turning the Pupil up- 
 wards, and inwards, and, with the afliftatice of the Superior 
 Oblique Mufcle, to pull the Eye forwards, thereby becoming an 
 antagonift to the Refti Mul’cks. 
 
 The two Oblique Mul'cles, on account of rolling the Eye, and 
 
 (ling it in the exorelfion of certain paffions, have been called 
 Rotatores, or Amatores. 
 
 VESSELS OF THE EYE. 
 
 The Frontal, Fafcial, and Temporal Arteries, which are 
 branches of the External and Internal Carotids, fupply the Pal- 
 pebrae, and communicate with tiiofe which are difperfed within 
 the Orbit. 
 
 Some final! branches of the Internal Maxillary Artery pafs 
 through the Inferior Orbitar Filfure, to be difperfed chiefly upon 
 the Periofteum of the Orbit and Fat of the Eye. 
 
 The Ocular Artery, which is a branch of the Internal Carotid, 
 partes though the Foramen Opticum, in company with the Optic 
 Nerve, and fupplies the Fat, Mufcles, and Ball of the Eye, and 
 aifo the Lacrytnal Gland and Tunics Conjunctiva. 
 
 The brandies which belong to the Ball of the Eye, have the 
 name ol Ciliares : — They perforate the Sclerotica in different 
 places, and are afterwards difperfed chiefly upon the Choroid Coat 
 stud Iris. 
 
 One branch of the Ocular Artery, called Centralis Retina, 
 perforates the Optic Nerve, and is difperfed upon the Retina. 
 
 The Veins which correfpond with the Arteries of the Eye, 
 communicate freely with each other, and pafs partly to the Exter- 
 nal jugular Vein, by branches fituated about the fore-part of the 
 Orbit, and partly to the Internal Jugular Vein by the Cavernous 
 Sinus. 
 
 NERVES OF THE EYE. 
 
 Befdes the Optic Nerve, already taken notice of, the Eye re- 
 ceives the Third and Fourth Pairs, and branches from the nrft 
 
part of the Fifth Pair, together with the Sixth Pair, and branch- 
 es from the Seventh. 
 
 The parts about the fore-fide of the Orbit are fupplied by 
 branches from the Fifth and Seventh Pairs; — the Ball of the Eye 
 by Nerves called Ciliary, wtfch come from the Third and Fifth 
 Pairs; — the fat, Mul les, Lacrymal Gland, &c. are fupplied by 
 the Third, Fourth, Fifth, and Sixth Pairs. 
 
 The ufe of the Eye is, to receive and colleft the rays of light, 
 in fuch a manner as to form upon the Retina the image or picture 
 of the object. which the Eye looks at ; and the point where thefe 
 different lays meet is called the Focus. 
 
 T he object is painted upon the Retina in an inverted manner, 
 the rays from above failing upon its under, and thole from be- 
 low upon its upper part; and it is fuppol'ed to be by habit, or 
 rather by in ft in £1, that we judge of the rcalFw nation of any ob- 
 ject. 
 
 That the rays of light may terminate diftin£Vly or the Retina, 
 it isnecedary that both the Cornea and Cryftalitne Lens (hould 
 have a certain degree of convexity. 
 
 If either the one or the other be too prominent, the Focus will 
 be formed before it reach the Retina, as is the cafe in ftiort-fight- 
 ed people, who require concave glafles to enable them to fee ob- 
 je£ts diftiinStly, at the proper and ordinary diftance. 
 
 If, on the contrary, the Cornea or Lens be too flat, or the 
 refractive power of the Humours be in any way dimir.ifbed, the 
 Focus will then be imperfeCtly formed, till the objedft is viewed at 
 a greater diftance than ordinary, as is the cafe with perfons ad- 
 vanced in life, to whom the afliftance of convex glafles become* 
 neceflary. 
 
 How an objeCt, viewed with both Eyes, appears Angle, has 
 been afcribed by the generality of Authors to cuflom and habit ; 
 and by others to inftinCt, which regulates the uniform motion of 
 the Eye, and the accurate application of both to one point. 
 
 The Eye is enabled to judge of, or accommodate itfeif to ob- 
 jects at different diftances, by the aCtion of its' Mufcles increa- 
 flng or diminifhing the length of its Axis, and by the motions of 
 the Iris allowing a greater or fmaller quantity of light to be 
 thrown into the Eye. 
 
40 
 
 OF TIIE NOSE. 
 
 Th'S Nofe, which is the Organ of Smell, and contributes to 
 the general purpofe of Refpiration, is divided into the External 
 Prominent Part, and the Internal Cavity, which is feparated by 
 the Septum Naiium into two fmaller Cavities ; — or, it is divided 
 into Hard and Soft parts. 
 
 The External part, or Nofe, properly fo called, is compofed 
 fuperiorly of Bones, inferiorly of Cartilages, and has a partial 
 covering from the Mufcles, and a general one from the common 
 Integuments. 
 
 On the ontfide of the Nofe are obferved, — the Radix , or upper 
 part j — the Dorfutn, or middle prominence ; — the Apex, or point ; 
 —the Alee, or lateral moveable parts and Columna, or under 
 part of the Partition next the Upper Lip. 
 
 The Ofleous part of the Nofe is formed by the OJfa Naji, pro- 
 perly fo called, the OJfa Maxillaria and Os Frontis, whieh con- 
 ftitute the upper and fore-part : 
 
 By the Os Ethmoides and OJfa Unguis, which form the upper, 
 inner, and lateral paits: 
 
 And by the OJJ'a Maxillaria Superioria, OJjfa Palaii, Os Spke- 
 Koides , OJfa Spongiofa Inferiora, and Vomer, which form the un- 
 der, inner, and back-part. 
 
 The two Cavities, or Nojlrils, terminate anteriorly in the Face, 
 and pofteriorly in the Fauces, and are much enlarged by the dif- 
 ferent Sinufes which communicate with them. 
 
 The under and fore part of the Nofe confifcs of five Cartilages, 
 cf a fomewha L regular figure, and of forne fmaller pieces, which 
 are more in egu :ar, and of ar. indeterminate number. 
 
 Of the five Cartilages, one is iituated in the middle, and the 
 other four laterally. 
 
 The middle Cartilage is the molt confi'derable, and fupports 
 the reft : It conftitutes the Cartilaginous part of the Septum Nari- 
 um, and is joined to the anterior edte of the Natal Lamella of the 
 Ethmoid Bone, to the anterior edge of the Vomer, and to the 
 fore-part of the Spinous Procefs of the Superior Maxillary 
 Bones. 
 
 Of the lateral Cartilages, two are placed anteriorly, form'ng 
 by their curved union the Tip of the Nofe ; and two pofteriorly, 
 which form the Alae Nali. 
 
41 
 
 • ' jg» m 
 
 Between the anterior and pofterior Cartilages, are fpaces 
 filled with additional Cartilages, the number, fize, and figure, 
 ■varying in different bodies. 
 
 The el.fticity of the Cartilages contributes to the defence of 
 the Nofe againft external injuries. 
 
 The Nofe is covered by the common Integuments, and per- 
 forated at its under and outer-part by the Duffs of Sebaceous 
 Glands, the contents of which may be readily fqueezed out by 
 the preffure of the Fingers. 
 
 The Cartilages of the Nofe are moved in different directions, 
 by the following Mulcle;, which have been alieady deter. bed, 
 viz. the Comprejfor Ndriutn, the Nafal part of the Frontal Mufcie, 
 the Levator and Depref'or Labii Superior is Alaqui Naji. — The 
 Nofe may alfo be moved by the neighbouring Mufcles, which, 
 in many inflances, become affiftants to the others. 
 
 The internal Nares or Cavities of the Nofe extend upwards to 
 the Cribriform Plate of the Ethmoid, and to the Body of the 
 Sphenoid Bone. 
 
 At the inner fide they are bounded by the feptum Narium, 
 which is formed by the Nafal Lamella of the Ethmoid Bone, 
 by the Vomer, and by the middle Cartilage of the Nofe. 
 
 On the outfide, or that next the Cheek, the Ofla Spongiofa 
 projeft a considerable way into their Cavities, and increafe the 
 Surface of the Membrane of the Note, for enlarging the Organ 
 of Smell. 
 
 In animals which fmell acutely, the Ofla Spongiofa are re- 
 maikably large and complex. 
 
 The bottom of the Noftrils runs directly backwards, fo that a 
 flraight probe may be palled through either of them to the 
 Throat. 
 
 In the fore-part of the Noftrils there are (1 iff Hairs, called 
 VibriJJ'ee, which prevent the Mucus from conftantly flowing out, 
 and infers, or other extraneous matter from entering. 
 
 The general Cavity of each Neftrii is divided by the Ofla Spon- 
 giofa into three Meatus, or Pajfages, which run from before back- 
 wards, and are defc; ibecJ by Haller according to their fixa- 
 tions, viz. 
 
 The Meatus Narium Superior , placed at the upper, inner, and 
 back-part of the Superior Spongy Bone. 
 
 The Meatus Meditis, fituated between the Superior and Infe- 
 rior Spongy Bones. 
 
 The Meatus Inferior, fituated between the Inferior Spongy 
 Bone and bottom of the Nofe. 
 
 The inlide of the Nofe is lined with a thick Spongy Membrane, 
 termed Mucofa, or Pituitaria cf Schneider, or Schneideri- 
 an a, which lines the whole internal Nares, and is" alfo' continued 
 
 VOL. II. 
 
to the different Sinufes, to the Le.crymal Sacs and Palatine Du£ts, 
 to < he Pharynx, Palate, and Euftachian Tubes. 
 
 This Membrane is veiy Vafcular and Nervous, and is the pri- 
 mary Oigan of Smeil ng. It is conftantly lubricated and pre- 
 ferred in a proper degiee of moifture by the Mucus of the Nofe, 
 which is dil’chaiged upon its Surface from numerous finall Fol- 
 licles. • 
 
 The different Sinufes of the Bones of the Head, after having 
 run obliquely backwards in a Iho it winding direftion, terminate 
 by fjnall openings in the Cavity of the Nofe. 
 
 The Frontal Sinufes pal's downwards into the anterior Ethmoid 
 Cells, which terminate in the upper part of the Nofe, behind 
 the beginning of the Lacrymal Sacs. 
 
 Befider. the P.flages common to the Frontal Sinufes and ante- 
 rior Ethmoid Cells, there are others proper to the P interior Eth- 
 moid Cells, which terminate in the upper and back-part of the 
 Nofe, near the openings of the Sphenoid Sinufes. 
 
 The Sphenoid Sinufes op^n, behind the Cells of the Ethmoid 
 Bone, into, the upper and bar k-part of the Nofe. 
 
 The Maxillary Sinufes open at their upper and inner fidcs, by 
 one, and fometimes two pillages, into the m ddle of the ipace 
 between the Superior and Interior Spongy Bones, nearly oppo- 
 fite to the under ed e of the Orbits. 
 
 At the upper part of the Maxillary Sinufes, Appendices, deferi- 
 bed by Haller, are fometimes found, which commun cate with 
 the Ethmoid Cells. 
 
 The Sides, or Walls of the Maxillary Sinufes, are formed of 
 thin Plates of Bone, excepting where the Pioc-efles project and 
 give them additional ftrength. Below, they have only thin Plates 
 between them and the Dentes Molares, the roots of which are 
 fometimes found to perforate the Septum. 
 
 The different Sinufes are lined with a continuation of rheMem- 
 brana Scbneideriana ; but in thefe it is thinner, lefs Vafcularand 
 Nervous, than that part of the Membrane which lines the gene- 
 ral Cavity of the Nofe. 
 
 They are conftantly moiftened, but not filled with a fluid. 
 
 The Sinufes increafe and modulate the voice : Their hollow 
 ftrufture renders the Bones lighter ; but they do not appear to 
 conftitute part of the Organ of Smell 
 
 Their paffages being directed backwards, prevent any kind of 
 extraneous matter from getting into them. 
 
 The Lacrymal Sac is a Membranous Canal, fituated in the 
 Lacrymal Groove, formed by the Superior, Maxillary, Lacry- 
 mal, and Infeiiur Spongy Bones. 
 
 TJie Ojfeous Du6l, in its defeent, runs a little obliquely back- 
 wards to the lower and lateral part of the Cavity of the Nole, 
 where it terminates at the inner and fore-part of the Antrum 
 Maxillare, under the Os Spongiofum lnferius, a little behind 
 
45 
 
 the anterior extremity of that Bone, and in a direct line upwards 
 from the fecond Dens Molaris. 
 
 The upper part of the Offeous Paffage forms only a femi-canal, 
 the under end a complete one. 
 
 The Lacrymal Sac is lituated in the upper part of the Lacry- 
 mal Gru ve, behind the Tendon of the Orbicularis Mul'cle of 
 tke Eye-lids. About a fourth part of the Sac. is fituated above 
 the Tendon, forming a kind of InteJUnum Cacurn, and the reft is 
 placed below. 
 
 Towards the inner angle of the Eye, behind the Tendon of 
 the Orbicularis JMiifcle, the Sac is perforated by the Lacrymal 
 
 The under part cf the Sac becoming a little narrower, but 
 without forming any Vasve, paffes into the Note, under the name 
 of Lacrymal Duct , Canalis Nafalis, or DuHus ad Nafum, and 
 term nates at the inferior extremity of the Offeous Canal. 
 
 The iubftance of the Lacrymal Sac and Duft is fimilar to that 
 of the Membrana Schneider tana, is deiended with the fame kind 
 of Mucus with which this Membrane is lubricated, and is firmly 
 connected to the Periofteum of the Offeous Canal. 
 
 The ufe of this paffage is, — to convey the fuperfluous Tears 
 to the Nofe, fo as to prevent them from palling over the Cheek. 
 
 The DuBus Incijivus, or Nafalo Palatinus of fcTENO, is a 
 fmall Canal, whicn, as has been already oblerved in the defcrip- 
 tion of the Bones, is only fomet mes met with in the Hu/nan 
 Body, though it is always to be found in the Ox, Horfe, Sheep, 
 &c. 
 
 When prefent, it takes its origin from a fmall Pit, formed in 
 the fore-part of the bottom of the Noftril, under the termination 
 of the Lacrymal Duft. It runs obliquely downwards and for- 
 wards, placed in fuch a manner as to receive and conduit Tears 
 into the Mouth. 
 
 The Arteries of the Nofe come chiefly from the external Ca- 
 rotids. 
 
 Thufe of the outer part of the Nofe come from the Facial and 
 Internal Maxillary Arteries; — thofe of the inner, from the 
 Maxiilares Internae; — and a few twi D s are furnifhed by t lie Ocu- 
 lar Arteries. 
 
 The Feins go to the External Jugulars ; — they likewife com- 
 municate with the Ocular veins, and of cotirle with the Lateral 
 Sinufes and Internal Jugul rs. 
 
 The Nerves with wh ch the outer part of -the Nofe is chiefly 
 fupvlied, come from the fecond branch of the Fifh, ar.d from 
 the Port o Dura of the Seventh Pa r. 
 
 The inner part is principally i'upplied by the Firft, or OlfaSory 
 Nerves, and by fame branches from the firlt and fecond portions of 
 the Fifth Pair. 
 
 Dufts 
 
44 
 
 OF THE EAR. 
 
 The Ear, or Organ of Hearing, is divided into the External 
 and Internal Ear. 
 
 EXTERNAL EAR. 
 
 The External Ear comprehends the Auricle, or Ear, properly 
 fo called, and the Meatus Auditorius Externus. 
 
 It is again divided into the Pinna, or Ala, which conftitutes 
 by much the^reater part of it ; — and Lobus, which is placed at 
 its under end. 
 
 Tlie Pinna or Ala, is chiefly compofed of Cartilage, and is 
 divided, at its fore-part, into i'evera] Eminences and Cavities, 
 which have obtained particular names, viz. 
 
 The Helix, or outer Bar, or Margin, fo called from 'ts wind- 
 ing dii edtion. It ariles beh nd at the Lobe of the Ear, furrounds 
 its upper edge, and termm tes below, nearly oppofite to its ori- 
 gin, divid n the Concha into two paits. 
 
 The Antihelix, Authelix, or inner Bar or Mar .■•in, which is 
 fituated within tiie former, and is compoied fuperiorly of two 
 Rid ges, un ting together below. 
 
 The Tragus, fo called from the Hairs which frequently grow 
 from it having a refemblance to the beard of a Goat. 
 
 It is a ftnall Eminence which lies over the Meatus Externus, 
 and is connefled to the under and fire-part of the Helix. 
 
 The Antitragus, fo named from its being oppolite to the Tra- 
 gus, below the pollerior ext.emuy of the Antihelix. 
 
 The Cavitas lunominata, fituated between the Helix and An- 
 tihelix. 
 
 T e Scapha, or FoJJ'a davicula.is , — compared in fiiape to that 
 of a B a., — iitua ed between the two 1 mbs of the Antihelix. 
 
 The Concha, fo tailed from its refemblance to a F fb-fhell of 
 that name. It is a la ge Cavity under the Amihclix, divided 
 by the Helix ntotwopa.ts, the inferior of which leads to the 
 Mea' ue Au .ilorius. 
 
 The back part of the External Ear exhibits only one confi- 
 de) able Eminence, which is the convex Surface of the Concha. t 
 
 The Lobus , which is the inferior foft p.ut of the Ear, is com- 
 pofed of Cellular Subfiance, with a tin all quantity of Fat. 
 
45 
 
 The Ear is covered by a continuation of the common Integu- 
 ments, which is thinner here than on the reft of the Body, and is 
 perforated in many parts by the mouths of Sebaceous Dufts, 
 which are placed immediately under the Skin. 
 
 The motions of the Ear, which are very limited, are regulated 
 by levergi Milfcles, fome of which are common to the Ear and 
 Head, and others proper to the Ear itfelf. The common Muf- 
 cles have been already defcribed. The Mufcies proper to the 
 Ear lie ctofe upon the Cartilage, and, in the generality of fub- 
 jefts, are fothin, white, and indiftinft, as to receive from fome 
 Authors the name of Mufcular Membranes. — They are as follow. 
 
 Helicis Major. 
 
 Origin: From the anterior acute part of the Helix, upon 
 which it afeends. 
 
 Insertion : Into the Helix. ... .. 
 
 ASiion: To pull that part into which it is inferied a little 
 downwards and forwards. 
 
 Helicis Minor. 
 
 Origin : From the under and fore-part of the Helix. 
 
 Infertion : Into the Helix, near the Filfure in the Cartilage op- 
 pofite to the Concha. 
 
 ASion : To contract the Fift'ure. 
 
 Tragicus. 
 
 Origin: From the middle and outer part of the Concha, at 
 the root of the Tragus, along which it runs. 
 
 Infertion : Into the point of the Tragus. 
 
 Action : To pull the point of the Tragus a little forwards. 
 
 Antitragicus. 
 
 Origin. From the internal part of the Antitragus, upon which 
 it runs upwards. 
 
 Infertion : Into the t ; p of the Antitragus, as far as the in- 
 ferior part of the Antihelix, where there is a Fift'ure in the Car- 
 tilage. - 
 
 ASion: To turn the tip of the Antitragus a little outwards, 
 and deprefs the extremity of the Antihelix towards it. 
 
 Transversus Auris. 
 
 Origin From the prominent part of the Concjia, on the Dor- 
 fum, or back part of the Ear. 
 
 Injertion .- Into the outhde of the Antihelix. 
 
 ASion: To draw the parts to which it is connefted towards 
 each other, arid to (fretch the Sea. ha and Concha. 
 
 The ufe of the External Ear is to crdleft the found, and con- 
 vey it to the Meatus Externus, — the Mufcies giving tenlion to 
 it, fo as to render the founds more diltinfl. 
 
 % At 
 
46 
 
 The Cartilage of the External Ear is conneEled to the Tem- 
 poral Bone by the common Integuments, and by its Mulcles; 
 and is fumiihed with Ligamentous Membranes, which fix it to 
 the roots of the Zygoma and of the Mafto-d Procefs. 
 
 The Meatus Auditorious Bxternus leads inwards, from the 
 Concha, and in i s courfe proceeds forwards and upwards, turn- 
 ing a little downwards at its farth'eft extremity, and terminating 
 at the Membrana Tympani. — The turns, however, are fo in- 
 confiderable, that the bottom of the paffage cun be readily leen in 
 a clear light, upon pulling the ear backwards.. 
 
 It is lbmewhat of an oval form, a 1 ttle comra&ed in the mid- 
 dle, and upwards of an inch in length. 
 
 Its outer end, which is a continuation of the Concha, is Car- 
 tilaginous, and has two or tjyce Interruptions or Fijfures in it. 
 
 On the upper and back-part of its circumference, there is a 
 Large Interruption terminating in an oblique M.-rgin, which is 
 tixed to the rough edge, at the under part of the Offeous portion 
 of the Meatus. 
 
 At the upper and back-part of the Meaius, the Cartilage has 
 but Jittle connection with the Bones, being there fixed by the 
 Skin which lines the Canal. 
 
 The Offeus Canal is continued from the Cartilage of the Mea- 
 tus, and is the longer of the two, particularly at the upper and 
 back-part of the Paffage. 
 
 The Meatus is lined with a continuation of the Skin, which 
 fills up the interruptions in the Cartilage, but is thinner than 
 on the reft of the Body. 
 
 Under the Skin of the Meatus, and near its outer end, there 
 are numerous fmall glands, of a yellowifh colour, placed in a 
 Reticular Subftance, formed of the Corpus Mucofum, and termed 
 Glandules Cerutninofa, which difeharge the Wax of the Ear 
 through fmall Excretory DuCIs. 
 
 The Arteries of the External Ear come anteriorly from the 
 Temporal, and posteriorly from the Occipital, both of which are 
 branches of the External Carotid Artery. 
 
 The Veins pafs partly to the External, and partly to the In- 
 ternal Jugulars. 
 
 The fore-part of the Ear is fupplied with Nerves from the 
 third or the Fifth, and from the Po'rtio Dura of the Seventh 
 Pair 5 the under and back-part, by branches from the firft and 
 f'econd Cervicles. 
 
 The Meatus Exfernus conveys the found from the Outer to- 
 wards the Inner Ear, and i 6 fuppofed to do this to greater ad- 
 vantage, on account of the winding nature of the Paffage. 
 
 The Wax lubricates the Paffage, and defends it from the in- 
 juries of the air, and being of a vifeid and bitter quality, affifts 
 in the exclufion of infefts. 
 
47 
 
 In the Foetus, the Meatus is entirely Cartilaginous, and only 
 adheres to an imperfect Bony Circle, in which the Membrana 
 Tympani is fixed. 
 
 At the inner end of the Meatus Externus, the Membrana 
 Tympani is fituated, which has its name from covering the outer 
 part of the Tympanum or Drum of the Ear. 
 
 It is firm, almoft: tranfiiarent, and of an oval form. 
 
 ' s fixed in a Groove which divides the Meatus from the 
 Tympanum. 
 
 It is very tenfe, but has a finall deprejjion in the middle next 
 the Meatus, with a correfpondiug convexity towards ,he Tym- 
 panum, where the extremity of the Malleus is fixed to it. 
 
 Its fituation is fomewat oblique, the upper part being turned 
 outwards, and the under inwards, To that the lower lide of the 
 Meatus is a little longer .han the upper. 
 
 It forms a complete Septum, and has no hole in it, fuch as has 
 been del'cribed by lome Authors. 
 
 It is formed partly ofa continuation of the Lining of the Mea- 
 tus, but chiefly of the Periofteum. 
 
 The Membrma Tympani has numerous finall Veffels from the 
 Temporal and Stylo- maftoid Arteries, which run m a radiated 
 manner, and which are moft abundant in the Fcetus. 
 
 It is the Conduftor of Sound from the Outer to the Inner 
 Ear. 
 
 In the Foetus, this Membrane is fixed in an impeTeft R'rtn- 
 of Bone, and, along with the Meatus, is covered with a Mut 
 cus Membrane, which defends the parts from the too ftrong 
 impulfe of Sound. 
 
 THE INTERNAL EAR. 
 
 The Internal Ear comprehends the Tympanum, Labyrinth, and 
 certain PaJJ'ages' leading into thefe. 
 
 The Tympanum, or Drum of the Ear, is fituated at the inner 
 fide of the Membrana Tympani, approaches to a hemifpherical 
 figure, and is about half an inch in width. 
 
 Btween the Tympanum and Cavity called Labyrinth, there is 
 an OJJeous Septum, which forms the bottom of the Tympanum, 
 where there are feveral Eminences, viz. 
 
 The Promontory, which forms the be'ginr:in« of the Scala 
 - ympani, and divides the Tympanum into” anterior and pofterior 
 regions. 
 
 A Protuberance at the upper and back-part of the Tympanum, 
 formed by the Aquseduftus Fallopii. 
 
 A Projection, called Eminentia tyramidalis Tympani, fituated 
 behind the Feneltra Ovalis, in which is the Paffage for the Sta- 
 pedius Mulcic. 
 
4S 
 
 An Eminence at the upper and fore-part of the Tympanum, 
 containing a iemi canal, for lodging part of the Tenfor Tym- 
 pani Mufcle. 
 
 In the Tympanum there are various Paffages, which communi- 
 cate with the neighbouring parts, viz; 
 
 The Iter a Palato ad Aurem, or Eujlachian Tube, which goes 
 off from the upper and fore- part of the Tympanum, and runs 
 obliquely forwards and inwards to the poiterior opening of the 
 Nollril, and terminates at its outer edge, above the arch of the 
 Palate. 
 
 The po'fterior part of the Tube is formed in the Pars Petrofa, 
 at the upper and outer part of the Canal for the Carotid Artery, 
 
 The anterior portion is formed above, by the Spinous Procefs, 
 and root of the Pterygoid Procefs of the Sphenoid Bone ; — and 
 below, by Cartilage and Membrane. 
 
 It is narrow next the Ear, where it can only admit the point 
 of a Surgeon’s probe ; but becomes gradually wider towards the 
 Nofe, where it terminates by an oblique opening with prominent; 
 fides, fufficiently large to admit a Goofe-quill. 
 
 It is lined by a Membrane fimilar to that of the Nofe, of 
 which it appears to be a continuation ; and on the edge of the 
 Mouth of the Tube, it is fo thick as to add confiderably to its 
 prominency. 
 
 The Euiiachian Tube preferves the balance of Air between the 
 Outer and Inner Ear, and prevents it from preffingtoo forcibly 
 upon the different Membranes placed in the fides of the Tym- 
 panum. 
 
 It has been fuppofed to convey the found of a perfon’s own 
 Voice to the Inner Ear; but experiment does not favour this 
 opinion, nor is it found to render Sound more diftinft when the 
 Mouth is open ; — though perl’ons who are dull of hearing 'are ob- 
 ferved frequently to liften after this manner. 
 
 The Cells of the Mafioid Procefs, which open into the upper 
 and back-part of the Tympanum, oppofite to, but a little higher 
 than the Euftachian Tube. 
 
 They are very irregular, and have many windings and turn- 
 ings, which communicate freely with each other, and are 
 lined, like the Cells of other Bones, with the Periofteum In- 
 ternum. 
 
 They nfiift the Tympanum in refle&ing the Sound. 
 
 In Quadrupeds which hear acutely, there are large Cavities 
 connefted with the Tympanum, which feem to fupply the place 
 of Maftoid Cells. 
 
 Above the Promontory, a Hole, called Fenefra Ovalis, the 
 upper and under edges of which are convex upwards, — for lodg- 
 ing the Bale of the Stapes. 
 
 The inner edges of this Hole are contracted bv a narrow bor- 
 der, upon which the end of the Stapes reds. 
 
49 
 
 Below the Fenellra Ovalis, and at the under and back-part of 
 the Promontory, a Hole, final ler than the former, called FeneJ 
 tra Rotunda. 
 
 It is ('laced obliquely backwards, and outwards, leads to the 
 Cochlea, but is Ihut up by a Membrane which affifts in com- 
 municating Sound to the Labyrinth. 
 
 1 he Sides, or Walls of the Tympanum, which- likewife affiftin 
 conveying Sound to the Labyrinth, are lined with Periofteum, 
 which isreflefted into the different Paffages leading from it. 
 
 The Cavitv of the Tvmpanum contains four fmall Bones, 
 called Officula Auditus, which form a chain ftretching acrofs from 
 the Membiana Tympani to the Labyrinth. 
 
 The OJJirula Auditus are, — -the Malleus, the Incus, the Os Or- 
 biculare, and the Stapes ; — ;htfe names being derived from lub- 
 ftances whi 'h they are fuppofed to refemble in fhape. 
 
 The Maileous, or Hammer,' confifts of a round Head, a fmall 
 Neck, a Manubrium or Handle, and two fmall Procefles, one in 
 the neck, long and vei y llender, and therefore called Gracilis } 
 the other in the upper end of the Handle, called ProceJJiu brevis. 
 
 The Handle is by fome Authors conftdered as one of the Pro- 
 cefies, and is then called the longeft of the three. It forms an 
 angle with the Neck, becomes gradually fmaller, and is bent, at 
 its extremity, towards the Membraria Tympani. 
 
 In the natural fituation, the Head is turned upwards and in- 
 wards, and the Handle down upon the Membrana Tympani, to 
 which it adheres. 
 
 The Incus, compared in fhape to an Anvil, but more refem- 
 bling one of the Dentes Molares, with its roots widely fep3rated, 
 is lituated behind the Malleus, and is formed of a Body, and 
 tvio Crura of unequal lengths. 
 
 The Body has a Cavity and tvjo Eminences , correfponding to 
 that part of the Malleus with wh-ch it is articulated. 
 
 The fhort Crus extends backwards, and is joined by a Liga- 
 ment to the edge of the Maltoid opening. 
 
 The long Crus is turned downwards, with the point a little 
 flattened, and bent inwards. 
 
 The Os Orbiculare is the fmalleft Bone of the Body, being 
 confiderably lefs than a grain of Muftard-feed. 
 
 It is articulated with the point of the long Procefs of the Incus, 
 and is fo firmly fixed to it, that in feparating the fmall Bones of 
 the Ear from each other, it is apt to adhere to the Incus, and has 
 on this account been frequently coniidered as a Procefs of that 
 Bone. 
 
 The Stapes is named from a ftriking refemblance it has to a 
 Stirrup. It is divided into Head, Crura , and Bafe. 
 
 The Plead is placed upon a fmall flat neck, and is articulated 
 with the Os Orbiculare. 
 
 Vol. II. E 
 
50 
 
 The Crura, like thofe of the Incus, are unequal in length, 
 and have a groove \viihin ; which is occupied by a Membrane. 
 
 The Safe is of an oval fliape, and has no perforation in it. 
 Its edges correfpond with thofe of the Feneftra Ovalis, with 
 which it is articulated. 
 
 The Stapes is placed horizontally, being nearly at a right angle 
 with the inferior Crus of the Incus. — Its two Crura are placed 
 •in the fame plane, — the longed backwards. 
 
 The final i Banes of the Ear are articulated with each other 
 by Capfular Ligaments, proportioned to their fize, and are cover- 
 ed by the Periofteum, which likewife fixes them to the Mem- 
 brana Tympani and Feneftra Ovalis. 
 
 Die fmall Bones have the following Mufcles fixed to them, 
 which ferve for their different motions. 
 
 Tensor Tympani, or Internus Auris. 
 
 Origin: From the Cartilaginous extremity of the Euftachian 
 Tube, near the entry of the Artery of the Dura Maier. From 
 thence, its Fle/hy Belly runs backwards in a Canal peculiar to 
 it, at the upper and inner part of the Olfeous Portion of the 
 Tube, being covered only by a thin plate of Bone. It fends off 
 a (lender Tendon, which makes a turn in the Tympanum, and 
 paffes outwards. 
 
 Infertion : Into the pofterior part of the Handle of the Malleus, 
 a little below the root of its long Procefs. 
 
 ASlion : To pul! the Malleus and Membrana Tympani in- 
 wards by which the Membrane is rendeied more concave and 
 tenfe, and better adapted for the impieflion of weak founds. 
 
 Laxator Tympani. 
 
 Origin : By a very fmall beginning, from the extremity of the 
 Spinous Procefs ot the Sphenoid Bone, behind the entry of the 
 Artery of the Dura Mater ; after which it runs backwards and a 
 little u p wards, at the ou tilde of the Eu It a chi an T ube, in a FifTnre 
 of the Os Temporis, near the Foffa which lodges the Condyle of 
 the Lower Jaw 
 
 Infertion: Into the long Procefs of the Malleus, within the 
 Tympanum. 
 
 Affion : To draw the Malleus obliquely forwards and outwards, 
 and thereby to render the Membrana Tympan i lefs convex, or to 
 relax it when Sounds are too ftrong. — Haller denies the ex- 
 iftence of Mufcular Fibres in this Subltance. — Sabatier de- 
 fcribes it, but doubts of its Mufcularity. 
 
 Stapedius. 
 
 Origin ; By a fmall Flefhy Belly, from a little caver n in the 
 Pars Petrofa, near the Cells of the Maftoid Procefs. Its Ten- 
 
5 L 
 
 don pafies forwards through a final! Hole in that Cavern, and- 
 goes into the Tympanum. 
 
 I : Tertian : Into the pofterior part of the Head of the Stapes. 
 
 Aftiou : To draw the Head of the Stapes obliquely upwards 
 and backwards, by which die pofterior part of its Bale is moved 
 inwards, and the anterior part outwards, and the Membrana 
 Tympaui thereby put upon the ffretch. 
 
 Labyrinth. 
 
 The Labyrinth , fo called from its Sinuofities and wind- 
 ings, is !. tutted attire inner-part of the Tvmpanum, and is 
 formed at the Vejribie, ° ocblea , and Semicircular Canals , together 
 with tit t.Canalis Faikfii and 'Meatus Auditorius Interims, 
 
 The '/efiitle, named from its forming a porch or entry to the 
 Cochlea arc! Semicircular Canals, isofan oval figure, nearly of 
 the fize and flnp’e of a clean grain of Barley, and is fituated at 
 the inner fide of the Safe of the Stapes. . 
 
 There are- three contiguous Cavities in the Veftible, one of 
 which, the Semi-oval, is fituated above; another, the Hemi~ 
 fpherical, below; and the third,- or Sulciform, which is the orifice 
 of the Aquse'duflus Veitbuli, is placed behind. 
 
 In the Veftible there are fcvcral Holes which communicate with 
 the neighbourin r parts, viz. 
 
 The Fenejira Ovalis fituated at the outfide, by which it com- 
 municates with the Tympanum. 
 
 A round Hole, fituated at tire fore and under-part, by which it 
 communicates with one of the Canals of the Cochlea. 
 
 Five Similar Foramina behind, by which it communicates with 
 the Semicircular Canals. 
 
 Next the Meatus Auditorius Interims, it has four or five 
 Cribriform Perforations , for the tranfmiflion of Nerves. 
 
 The Cochlea is fituated next the anterior extremity of the Os 
 Petrofum, and at the fore-part of the Veftible, in fuch a man- 
 ner as to have it; Bale towards the Jvleatus Auditorius Interims, 
 and its Apex in theoppofite direftion, — or facing outwards. 
 
 It has two Canals or Gyri, called Seal a, from a luppofed re- 
 femblance to Stair-cafes, the Gyri or turns of which are very 
 ciofe to each otner, and run in a fp : ral d reflion, like the Shell 
 of a Snail, from which the par. has obtained its name. 
 
 The Cochlea forms tvuo Circumvolutions or Tarns and a half, 
 the firft of which is much larger and wider than the other Turn 
 and a half, which become fuddenly fmaller. 
 
 The two Canals are upon the fame level, the inner one next 
 the Bafe, and the outer next the pont of the Cochlea. 
 
 The Gyri go round a Nucleus, Axis, or central Pillar, which 
 is nearly horizontal, and is formed of tvuo hollo vs Cones , with 
 their points turned to each other, the one termed Modiolus , fro® 
 
52 
 
 its refemblance to the Spindle of a winding Stair-cafe, the other 
 Infundibulum, or Funnel. 
 
 The Modiolus forms the inner and larger portion of the central 
 Pillar, and is that Cavity feen in the under and fore-part of the 
 Meatus Auditoi ius Internus. 
 
 It lodges that branch of the Portio Mollis of the Seventh Pair 
 of Nerves, which goes to the Cochlea, and is Cribriform, or full 
 of fmall Holes for the paffage of the twigs of that branch. 
 
 The Modiolus confilts of two Plates, with numerous Cells 
 and Pajfages between them, and terminates in the middle of the 
 fecond Gyrus of the Cochlea. 
 
 The Infundibulum is an imperfect Funnel, the Apex of which 
 is common with that of the Modiolus, and the Bafe is covered 
 by the Apex of the Cochlea, which is termed Cupola. 
 
 Between the Scalae of the Cochlea there is a Partition, called 
 Lamina Spiralis, or Septum Scala, the larger portion of which, 
 next the Modiolus, is formed of Bone : The remainder, or that 
 part next the oppofite fide of the Scalae, is Membranous, and 
 termed by Valsalva Zona Gochlce. — This drops out by macera- 
 tion, fo as afterwards to leave only a partial Septum. 
 
 The Offeous part of the Lamina Spiralis is compofed of two 
 extremely thin Cribriform Plates, which gradually approach each 
 other at their oppofite edges, where they are perforated by numer- 
 ous Holes. 
 
 The termination of the Lamina Spiralis, and of the Scala 
 Tympani, forms a Hamulus, or fmall Hook, which projedls into 
 the Infundibulum. 
 
 One of the Canals or Scalae of the Cochlea, opens into the un- 
 der and fore- part 'of the Veliible, and is termed Scala Vefibuli: 
 The other, which is the fmaller of the two, communicates with 
 the Tympanum by the Feneftra Rotunda, and is called Scala 
 lympani. 
 
 The Partition between the two Gyri or Turns of the Cochlea, 
 like the Ofleous part of the Lamina Spiralis, is formed of two 
 Plates, with a fmall Cavity between them. 
 
 The Volute, or Spiral of the Cochlea, begins below, runs for- 
 wards, and then round, fo as to form, as has been already men- 
 tioned, two Circles or Turns and a half, the direction of the 
 Gyri correfponding with thole of the Shell of a Snail. 
 
 The Canals of the Cochlea are conical, becoming gradually 
 fmaller towards the Apex, where they communicate freely with 
 each oilier, through the medium of the Ini umbbulum. — T his 
 communication is called by Cassebohm, who ves thr ful.ePc 
 Treatif. upon the Ear, Canalis ",c alarum Cot" munis. 
 
 The Semicircular Canals are three m numb: r, — the Superior or 
 Vertical,— the Pojlerior or Oblique,— and the Exterior or Hori- 
 zontal. 
 
53 
 
 The Superior is placed tranverfely, in the upper-part of the 
 Pars Petrofo, with its convex fide upwards. 
 
 The Pojierior is farther back than the former one, and is pa- 
 rallel to the length of the Pars Petrofa, with the convex fide turned 
 backwards. — One of its extremities is placed above, and the other 
 below, the upper extremity joining with the internal one of the 
 Vertical Canal, by which a common Canal is formed. 
 
 The Exterior is lei's than the other two, which are more of an 
 equal fize, is placed next the Tympanum, and has its extremities 
 and curvatures nearly , upon the iame plane;— with the curve 
 placed backwards. 
 
 Each of the Canals forms upwards of three-fourths of a circle, 
 can admit the head of a fmall Pin, and has an Enlargement, 
 Ampulla, or Cavitieo Elliptica, at one end, the other extremity 
 being nearly of the lame fize with the reft of the Canal. 
 
 The Orifices are only five in number, two of the Canals ha- 
 ving a common termination. OFthefe Orifices, three. are fifua- 
 ted at the inlide, and two at the outfide of the Vefti.ile, into the 
 pofterior part of which they open. 
 
 In the bottom of the Meatus Auditorious Internus, which is 
 fituated in the pofterior Surface of the Pars Petrofa, there is a 
 large under, and a final 1 • upper Fojj'ula, feparated by a fharp 
 Ridge. 
 
 The fore-part of the inferior Foffula leads towards the Coch- 
 lea, and is perforated with numberlefs fmall Holes, through which 
 branches of the Portio Mollis of the Seventh Pair of Nerves pals 
 to the Cochlea. 
 
 One Hole in the centre, larger than the reft, tranfmits a branch 
 of that Nerve to the Infundibulum. — This Hole, however, is 
 frequently enlarged, in confequence of the Bone, which is ex- 
 tremely thin, being broken while preparing it. 
 
 In the back-part of the inferior Foffula, three or four Cibri- 
 form Holes appear, for the tranfmiffion of branches of that part 
 of the Portio Mollis deftined for the Veltible and Semicircular 
 Canals. 
 
 In the-upper Foffula of the Meatus Internus, there are t<wo 
 Paffages, one pofterior and fmaller, tranfmitting Nerves into the 
 Elliptical Cavity of the Veftible. 
 
 The other, the anterior and largeft, is termed Canalis or 
 Aqu&duBus Fallopii , — from a refemblance it bears to an IraFan 
 Aqueduct, and l’erves for a tranfmiffion of the Portio Dura of 
 the Seventh Pair of Nerves. 
 
 The Canal of Fallopius goes through the upper-part of the 
 Pars Peirola, paffes downwards and backwards between the 
 Foramen Ovale and external Semicircular Canal, and terminates 
 m the Foramen Stylo-Maftoideum. 
 
 Vol. II. E 2. J 
 
In its pafTage through the Pars Petrofa, it communicates with 
 the Foramen lnriominatum, lituated on the upper and tore-part 
 of the Procefs. 
 
 In Children, the Labyrinth is almoft as large as in Adults, its 
 Subftance complete and hard, "while the Bone which furrounds it 
 is foft and fpongy ; on which account it is eafily feparated from 
 the reft of the Pars Petrofa. 
 
 The different Cavities and Paffages of the Labyrinth are lined 
 with the Periofteum, which in the Veftible fills the Feneftra 
 Ovalis, and of confequence covers the Bafe of the Stapes. 
 
 The Perioftea of the t^o Canals of the Cochlea form, by their 
 union, the Membranous portion of the Lamina Spiralis, which, 
 together with the Offeous part, completes the Septum between the 
 two Scalae. 
 
 The Periofteum of the Cochlea alfo aftifts that of the Tym- 
 panum, in forming the Membrane of the Feneftra Rotunda, 
 and which is fome, times called Membrana Tympani Secundarii , 
 from a refemblance to the Membrana Tympani, and from being, 
 like it, a lit.le concave on the outer, and convex on the inner 
 Surface, or where it faces the Scala to which ii belongs. 
 
 Befides the Periofteum, the Veftible, Cochlea, and Semicir- 
 cular Canals contain a Pulpy Membrane, upon which the Portio 
 Mollis is irregularly difperfed. 
 
 In the Veftible, the Pulpy Membrane forms a Sac, in ftiape 
 vefembling that of the Offeous Cavity which contains it, and 
 which is deferibed and beautifully deliniated by Scarpa. 
 
 When the Sac is laid open upon the upper and outer-part, a 
 Partition appears, of the nature of the Sac, termed by Dr. 
 Meckel, Septum Vejlibuli Nervofo-membranaceum. 
 
 In the Cochlea, the Pulpy Membrane is in contadft with the 
 Periofteum, but can be feparated from that Membrane without 
 ■ much difficulty. 
 
 In the Semicircular Canals, it is at fome diftar.ee from the- 
 Periofteum of ihefe Bones, and is confiderably fmaller, but, like 
 them, it forms diftinft Tubes, which communicate with the 
 Veftible. Like the Offeous Canals alfo, the Membranous Canals 
 form Ampullae, or Elliptic Cavities at one end. 
 
 The Arteries of the Labyrinth aril'e by one or two fmall 
 branches, chiefly from the Vertebral Artery, and pafs through 
 the Ci ibr fo. m Plate, at the bottom of the Meatus Externus 
 which beiongs to the Labyrinth. 
 
 From the Labyrinth one or two Veins return, and terminate in 
 the end of the Lateral Sinus. 
 
 The Cavity of the Veftible contains no Air, but is conftantly 
 filled with a Watery Fluid, fuppofed to be kcreted from the Ar- 
 teries of the Periofteum, and which is found to referable the 
 Aqueous Humour of the Eye. 
 
5.5 
 
 The Aqueous Fluid fills the Veftib'e and Seal* of the Coch- 
 lea, and likewife furrounds the Membranous Semicircular Ca- 
 nals. 
 
 The Aqua Labyrinthi is confidered as a medium by which 
 founds are communicated from the Membrane filling the round 
 and oval Holes, and from the Bafe of the Stapes to the Pulpy 
 Membrane placed in it. 
 
 The fuperfluous part of the Aqua Labyrinthi is fuppofed by 
 Cotun nius to be carried off by two fmall Conical Duffs, more 
 particularly deferibed by h.m than by fome preceding Anato- 
 mifts, who were partly acquainted with them, but confidered 
 them as Blood-veffels. 
 
 One of the Aquedufts of Cotunnius, called Aquaduffus 
 Cochlea, begins at the under-part of the Scala Tympani, near 
 the Feneftra Rotunda, and after palling through the Pars Petro- 
 fa, is feen, in the figures he gives of it, terminating by a wide 
 triangular opening, upon the furface of the Dura Mater, be- 
 tween the paffages of the Seventh and Eighth Pair of Nerves. 
 
 The other Du ft, called Aqueeduffus Vefibuli, begins under the 
 termination of the common Canal, in the Veilible, from which 
 it defeends, and terminates by a triangular opening between the 
 Layers of the Dura Mater, behind the Meatus Internus, and 
 half way between the upper edge of the Pars Petrofa and Diver- 
 ticulum of the Internal jugular Vein. 
 
 For a jull account of thefe Duffs, and of the other parts of the 
 Labyrinth, fee a Description of thetn by Dr. Meckei, of Berlin. 
 
 The Nerves of the Labyrinth are derived entirely from the 
 Seventh Pair. 
 
 The Auditory Nerve is compofed of two branches, one of 
 which is called Portio Dura, and is harder than the other, ter- 
 med Portia Mollis. 
 
 The Trunk of the Auditory Nerve paffes into the Meatus Ex- 
 ternus, covered by the mvefting Membrane of the Brain. 
 
 The Portio Dura goes through the Canalis Faliopii, fending 
 off, in its paffage, branches through Perforations in its fides, to 
 the Stapedius Mufcle and Malloid Cells. 
 
 One refleffed branch paffing through the Foramen Innomina- 
 tum, in the Pars Petrofa, forms a conneftuon between the Por- 
 tio Dura and the fecoad part of the Fifth Pair. 
 
 Another, called Chorda Lympani, paffes aerols the Cavity of 
 the Tympanum, between the inferior Crus of the Incus and 
 handle of the Mail us, and at the mtfide of the Euftachian Tube, 
 to join the Lingual "ranch of the Fifth Pair. In its paffage it 
 fuppfes the Mufcles of the Malleus, and Membranes, See. of 
 the Tympanum. 
 
 The remainder of the Portio D uais Tfperfed upon the Face, 
 
 The Port 19 Mall.' is divided into two principal parts, —one to 
 the Cochlea, the other to the Vchibie, 
 
56 
 
 The branches of the Cochlea pafs through the Cribriform 
 Plates of the Modiolus, to the Pulpy Membrane lying in the 
 Sc alas. 
 
 The branches run between, and likewife on the out-fide of 
 the Partitions which devide the Cochleae into Gyri, and the 
 Gyrt into Scalae, and are large and numerous in proportion to 
 the part they fupply. 
 
 The large ft and mod numerous of thefe branches are difperfed 
 upon the Lamina Spiralis, where they form an intricate Plexus, 
 the Thieads of which at e at fir (l opaque, but are afterwards of 
 the colour of the Retina of the Eye. 
 
 The branches terminate, and appear alfo to meet upon that 
 part of the Pulpy Membrane, which is mod diftant from the Mo- 
 diolus. 
 
 Through the Cribriform Plate, common to the Modiolus and 
 Infundibulum, the laft branches of this portion of the Nerves 
 pafs, to be fpread out upon the Membiane lying within the In- 
 fundibulum . — For a particular defcription oj that part of the 
 Fort to Mollis difributed to the Cochlea and oj the Cochlea it- 
 felf, fee Dr. Monro’s Treat j'e on the Ear. 
 
 Or that part of the Portio Mollis deftined for the Veftible 
 and oein'cn cular Canal one branch goes through the pofttrior 
 Hole in the upper-part of the Meatus Internus ; rhe reft pafs 
 through the holes 'n the under and back part of the Meatus, 
 already pointed out in the defcription of that Paffage. 
 
 After perforatiu the Foramina, the Nerves are i'een firft in 
 diftinft Plexus, but become af towards tranfparent, and are loft 
 upon the Sac comuned in the Veftible and upon the Ampulla of 
 the Membranous Semicircular Canals. 
 
 The Po> 'lo Mollis * s the primary part of the Organ of Hearing, 
 to which alt tin. ...her ^aris are fu f.rvient, ai d may be regard- 
 ed as being of the fame lervice to the Ear, as the Retina is to the 
 Eye. 
 
$1 
 
 OF THE MOUTH , Tongue, AND 
 THROAT. 
 
 WITH THEIR APPENDAGES, 
 
 MOUTH. 
 
 The OJfeous Parts of the mouth are,— the OJj'a Maxillaria Su- 
 per; ora, the OJj'a Palati, the Maxilla Inferior, and the Teeth j 
 —all of which have been already defcribed. 
 
 The Sojt Parts of the Mouth confift of the Lips and Cheeks , 
 the Gums , the Palate, the Velum Palati the Uvula, the Tongue, 
 the Membrane lining the Mouth and the Salivary Glands. 
 
 The Lips and Cheeks are principally compofed ofMulcles, are 
 covered on the outfide by the common Integuments, and lined 
 within by the Membrane of the Mouth, under which there are 
 numerous Mucous Glands, which obtain their names from their 
 fituations. 
 
 The intervening fpace between the Mafleter and Buccinator 
 Mufcles is occupied by a large quantity of Fat, which gives form 
 to the Face. 
 
 The Membrane of the Mouth is covered with fine Villi ; but 
 thefe are mod conspicuous upon the edges of the Lips, as may 
 be readily feen after a fine injection, or after macerating the parts 
 till the Cuticle can be feparated. 
 
 From the edges of the Lips, the Common Integuments (now 
 become extremely thin) are converted into the Membrane which 
 is continued into the Cavity of the Mouth, and which, oppofite 
 to the Dentes Incifores of the Upper and Under Jaws, forms a 
 ftnall Doubling or Franum, which fixes the Lips more firmly to 
 the Jaws. 
 
 The Lips are ferviceable in the general purpofes of Speaking, 
 Eating, Drinking, See. 
 
 The Gums cover the tides of the Alveolar Border of both Jaws, 
 pafs in between the different Teeth, and funounu and adhere 
 firmly to the Collar of each. 
 
 The Subltanceof the Gums is of a denfe nature, veiy Vafcu- 
 lar, and the Veffels united by a compact Cellular Subftance. 
 
58 
 
 They may be fnid to confift of the Common Membrane of the 
 Mouth and the Periofteum of the Jaws intimately conneffed. 
 
 They feme as a covering to the Jaws and affift in the feeuiity 
 of the Teeth, 
 
 The Arteries of the Lips, Cheeks, and Gums, are from the 
 Facial, Temporal, and Internal Maxillarie?, which are derived 
 from the External Carotids. 
 
 The Veins go chiefly to the External, -and partly to the Inter- 
 nal Jugulars. 
 
 The Nerves rome from the firll and fecond branches of the 
 Fifth Pair, and nll'c from the Port'o Dura of the Seventh Pair. 
 
 * he Palate ; s divided into the Palatum Dure and Palatum 
 Malle. The forrner is compofea of the Palate-plates of the Up- 
 per Jaw, and is covered by the Periofteum and common Mem- 
 brane ot tile Mouth, which prevent the Bones from being in- 
 jured. 
 
 The Membrane which covers the Bones of the Palate forms 
 numerous Ruga?, which aflift in the divifion of the Food. 
 
 It is nearly of the. fame ltru£Iure with that of the Gums, but 
 perforated by the Dufts of the Palatine Glands, for th: excretion 
 of Mucus, which ferves to lubricate the Palate, and nffilts in 
 thflblving the Food. 
 
 The Palatum Molls, Velum Pendulum Palati , or Soft Palate, 
 is that pai t which depends from the poflerior edge of the Ofl'a 
 Pala'i, and from the Pterygoid Procefl’es of the Sphenoid Bone, 
 and forms a Partition between the Nofe and Mouth. 
 
 It is compofed of the Membranes which line the Nofe and 
 Mot th, at id of the expanfions of the Circumflex and Levator 
 Palati Mufcles, and numerous Mucous Glands which fei ve to 
 lubricate he Mouth and Throat, anti facilitate deglutition. 
 
 The Palatum Molle conducts the Fluids of the Nofe into the 
 Mouth, and afls like a Valve in preventing what we fwallow from 
 pafiing into the nofe. 
 
 In the middle of the poflerior edge of the Velum Palati, the 
 Uvula or Pap of the Throat, takes Its orgin, and hangs pen- 
 dulous, from the Velum over the root of the Tongue. 
 
 It is of a Conical farm, is covered by the Membrane of the 
 Mouth, and has a fmnll Mufcle wilhin it, by which it is eleva- 
 ted and ihortened , — its other motions depending upon the Muf- 
 cle ; of the Palate. 
 
 The ufe cf the Uvula in Speaking and in Deglutition, is evi- 
 dent from the inconveniencies which refult from its being deftroy- 
 ed by dileafe. 
 
 The Arteries of the Palate, See, come from the Facial, and 
 Internal Maxillary. 
 
 The Veins go the External and Internal Jugulars.' 
 
 The Nerves are chiefly from the l'econd of the Fifth, with 
 , fome twigs from the Eighth Pair. 
 
59 
 
 Tongue. 
 
 The Tongue is of an Oval form, and is divided into Safe , 
 Body and Apex. 
 
 The Safe, or pofteror part of the Tongue, isconneCfed to the 
 Os Hyoides, and by the medium of this, to the adjacent Bones 
 and Mufcles. 
 
 The Body, or middle part of the Tongue, terminates anteri- 
 orly in the loofe moveable point. 
 
 On theDorfum or upper Surface, there is a Lbtea Mediana, or 
 middle Groove, running longitudinally, and dividing it into two 
 lateral convexities. 
 
 The inferior Surface, which reaches only from the middle of 
 the Tongue to the po : nt, is connected to the parts below it by the 
 Sublingual Ligament, or Franum Lingua, which is a doubling 
 of the Skin, or lining of the Mouth. 
 
 The (ides of the Tongue are fixed to the Lower Jaw and Sty- 
 loid Procefies, and pans adjacent, by Membranous Ligaments. 
 
 The Ton. ue is chiefly compofed of the Fibres of the Mufcles 
 which fei ve for its motions. — Thefe Fibres are difpofed in vari- 
 ous directions, and intermixed with a Medullary Fat. 
 
 The upper and lateral pans of the Tongue are compofed of the 
 Stylo-Glofli. — Its middle portion, between the two former Muf- 
 cles, is formed of the Linguales. — The lower part is chiefly 
 formed of the Genio-Gloffi ; — and behind, the Stylo-Glofli en- 
 ter into its compofition. 
 
 The Tongue is covered by a continuation of the common In- 
 teguments, which are preferved foft and moilt by the Saliva. 
 
 The Cuticle forms Vaginae for receiving the Subftances called 
 Papilla. 
 
 The Corpus Mucofum of the Tongue is thicker than in other 
 parts of the Body, but more moift. 
 
 The third covering of the Tongue, the Cutis Vera, is remark- 
 ably Nervous. — The Papillae, which take their origin from it are 
 very Vafcular, efpecially near the Apex of the Tongue, but are 
 awantingon its under furface. 
 
 The Papilla are divided into three kinds, the Maxima, Media, 
 and Minima. 
 
 The fii It clafs, called Papilla Maxima, Lenticulares, or 
 Lapilata, are by much the lar eft, and of a Lenticular form, 
 having round Heads and fhort Stems. 
 
 They are placed at the Bafe of the Tongue, in fupcrficial Fol'- 
 fulae, and are diloerfe : in inch a manner as to form an angle 
 with its point backwards. 
 
 They are Glands of To Saliv; ry kind, and have each of them 
 a fmall Perforation in the middle of its convex SuT^ce, for the 
 excretion of Mucus. 
 
GO 
 
 Befides the Paplllse Capitatge, there are numerous Mucoy , 
 Follicles, which cover the greater part of the Surface of the root 
 of the Tongue. 
 
 At the root of the Tongue, and behind the angle formed by 
 the Papillae Maximse, there is a Hole, called Fo> amen Case uni of 
 Morgagni, by whom it was firft deferihed. 
 
 It penetrates only a fmall way into the Subftanceof the Tongue, 
 and receives the Mouths of feveral Excretory Dufts which termi- 
 nate in it. 
 
 The fecond clafs called Papilla Mediae, or Semi -lenticular es , 
 are much fmaller than the former, and aie fcattered over the up- 
 per Suilace of the Tongue, at fome diftance from each other. 
 
 They are of a Cyndrical form, and terminated by a round ex- 
 tremity. 
 
 The third clafs, termed Papilla Minima, or Conica, cr Vil- 
 lofa, are by much the moft numerous, but very minute. They 
 occu; y almoft the whole upper Surface of the Tongue, but are 
 moft abundant towards the Apex, where the fenl'atipn of Tafte is 
 moft acute. 
 
 This and the fecond clafs have been fuppofed to be formed 
 chiefly of the extremities of Nerves, and to conftitute the real Or- 
 gan of Tafte ; though other parts, as the Palate, and even the 
 Pharynx and Efophagus, poflefs the faculty of Talte in a certain 
 degree. 
 
 The principal Blood-veflels of the Tongue are large in propor- 
 tion to the fize of that Organ. 
 
 They are called Linguales, or Ranina, on account of the dark- 
 coloured branches which appear under the Tongue. 
 
 The Arteries, wh ch are branches of the External Carotids, are 
 not found to communicate fo freely on the oppofile fides of the 
 Tongue, as they do in other parts of the Body. 
 
 The Veins open chiefly into the External Jugulars. 
 
 The Nerves like the Arteries, are large and numerous, and 
 have little connexion on the oppofie Tides. 
 
 They come from the F fth. Eighth, and N. nth Pair: . 
 
 The firft let fupply the pans next the point of the Tongue, 
 and are therefore confidered as being principally concerned in con- 
 veying the fenfation of Tafte. 
 
 The fecond let fupply the root and the third the middle of the 
 Tongue, and are chiefly difperfed upon its Mufcles. — There is 
 a confidera'de intermixture, however, between the three fets on 
 the fame fide. 
 
 Befides being the principal Organ of Tafte, the Tongue is the 
 chief inftrument of Speech, and of the ai t, eolation of the Voice, 
 —It alfo aflifts in Manducation, Deglutition, Spitting,’ Suck- 
 ing, &c. 
 
 The Salivary Glands ronfift of three large Glands on eacn 
 fide of the Face, viz. — the Parotid, the Submaxillary, and the 
 
61 
 
 Sublingual ; — befides many fmall Glands, named from the parts 
 to which they belong. 
 
 They are of a yellowifh colour, and irregular on their Surface, 
 being of the Conglomerate kind. 
 
 The Parotid Gland, which is the larged of the Salivary Glands, 
 is named from its fituation near the Ear. 
 
 It occupies the whole fpace between the Ear, Maftoid Procefs, 
 and the angle of the Lower Jaw. 
 
 It extends fuperiorly to the Zygoma, and anteriorly to the 
 Mafleter Mufcle, part of which it covers. 
 
 The under end of it lies contiguous to the Submaxillary Gland. 
 
 From the different parts of the Gland, numerous fmall branch- 
 es arife, which join together to form a large Duff, fometimes 
 called StenS’s Salivary Duel, or Ductus Superior, which paffes 
 from the upper and fore-part of the Gland. 
 
 The Parotid Duff is of a white colour and large fize, but, 
 from the thicknefs of its Coats, the Cavity is fmall in propor- 
 tion to the outfide of the Duff. 
 
 It paffes anter orly, in a tranfverfe direffion, over the Tendon 
 of the Maffeter Mufcle, by which it is free from compreffion, and 
 defeends a little to perforate the Buccinator Mufcle, oppofite to 
 the fecond or third Dens Molaris of the Upper Jaw. 
 
 In crofTmg the Maffeter Mufcle, it receives fometimes one, 
 fometimes two minute Duffs, from an equal number of fmall 
 Glands, called by Haller, Glandules AcceJJbria;. 
 
 The Inferior Maxillary, or Submaxillary Gland, is fmaller and 
 rounder than the Parotid, and is fituated on the infide of the an- 
 gle of the Lower Jaw, between it and the Tendon of the Digaf- 
 tric Mufcle. 
 
 From the upper and fore-part of this Gland, aDuffarifes, 
 called by fome Authors Duftus Whartonii, or Ductus Inferior , 
 which is much thinner in fubftance than the former Duff, but 
 longer. 
 
 It paffes forwards between the Mylo-Hyoideus and Genio- 
 Glofl'us Mufcles, along the under and inner edge of the Sub- 
 lingual Gland, to the fide of the Fraenum Linguae, and terminates 
 behind the Dentes Incifores, by a fmall orifice, in form of a Pa. 
 pilia. 
 
 The Sublingual Gland is fmaller and fofter than the Submaxil- 
 lary, and is flat, and of an aval form. 
 
 It is fituated under the anterior portion of the Tongue, above 
 the Duff of the inferior Maxillary Gland near the Lower Jaw, 
 between the Myio-Hyoides and Genio-hyogloffus Mufcles, the 
 former of which l'uftains it. 
 
 Its extremities are turned forwards and backwards, and the 
 edges obliquely inwards and outwards. 
 
 It is covered by a continuation of the Skin of the under fide of 
 the Tongue, which fixes the Gland in itsp ! ace. 
 
 Vol. Jf. F 
 
612 
 
 It opens by feveral orifices arranged in a line near the Gums, a 
 little to the outfide of the Fraenum. 
 
 In many Quadrupeds, there is a diftinfl dud! belonging to this 
 Gland, like that of the Submaxillary 
 
 Sometimes this Gland fends off a Branch which communicates 
 with that of the Submaxillary, but generally it is otherwife. 
 
 The ftnaller Glands of the Mouth are in great nnmbers, lying 
 between the inner lining of the Mouth and its Mufclcs, and de- 
 riving their names from their fituations. 
 
 They are fmail fimple Glands, each fending a duff, which 
 perforates the Skin of the Mouth, and opens into its Cavity. — 
 They confift of — 
 
 The Bucca.les, which are placed all over the Cheek, but moft 
 plentifully near the termination of the Parotid Dudt ; 
 
 The Labiales, lying on the infide of the Lips j 
 
 The Palatine, upon the Palate ; and 
 
 The Linguales, at the root of the Tongue. 
 
 The Arteries of the Salivary Glands are from different Branch- 
 es of the External Carotids. 
 
 The Parotid is fupplied from the Temporal , the Inferior Max- 
 illary from the Facial, and the Sublingual from the Lingual Ar- 
 tery. 
 
 The Veins of thefe Glands go to the External Jugulars. 
 
 Their Nerves are chiefly from the third part of the Fifth, 
 and from the P«rtio Dura of the Seventh Pair. 
 
 The Salivary Glands ferre for the fecretion of the Saliva, 
 which they pour out in large quantity, and which is promoted by 
 the motion of the Lower jaw. — The Saliva afiifts in the folution 
 of the food in the Mouth, in lubricating the throat for its paffage 
 downwards, and in the digeftion of it in the Stomach. 
 
 THROAT. 
 
 The Throat confifh of the Arches of the Palate , of the Pharynx 
 and Larynx, with the Mufcles, Vejfels, Nerves , &c. which fur- 
 round them. 
 
 The Arches of the Palate are two in number, in each fide of 
 the Throat, one of which is termed the Anterior , the other the 
 Poflerior. 
 
 They are formed of a Doubling of the Skin, with a few feat- 
 hered Mufcular Fibres. 
 
 The Anterior arifes from the middle of the Velum Palati, at the 
 fide of the Uvula, and is fixed to the edge of the Bafe of the 
 Tongue. t 
 
T'he Pojlerior has its origin likewife from the fide of the Uvu- 
 la, and patfes downwards, to be inserted into the fide of the 
 Pharynx. 
 
 The Anterior Arch contains the Circumflex Mufcle of the Pa- 
 late, and, with its fellow on the oppofite fide, forms the open- 
 ing into theThioat, called Ijihmus Foucium. 
 
 The Pol'terior Arch has within it the Levator Mufcle of die Pa- 
 late. 
 
 Between the Anterior and Pofterior Arches, and clofe by th-s 
 fides of the Bale of the Tongue, the Amygdala, Tonfils , or Al- 
 monds of the Ears are fitv.ated. - 
 
 They are of a reddifh coLur, of the figure of Almonds, full 
 of Cells which communicate with each other, and have large ir- 
 regular openings, which convey the Mucus into the Throat, the 
 discharge of which is promoted by the motion of the furrouiid'- 
 ing parts. 
 
 . Pharynx. 
 
 The Pharynx, fo called from its conveying Food to the Sto- 
 re tch, and Air to the Lungs, is a large Mufcular Bag, in form 
 of an irregular Funnel, with the Tube called Efophdgus defend- 
 ing from it, and forming the under end of that Funnel. 
 
 It is bounded above by the Cuneiform Procefs of the Occipital 
 Bone, the Pterygoid Procelfes of the Sphenoid Bone, and back- 
 part of the Jaws, with all of which it is intimately connefted. 
 
 The anterior margins of its Flelhy parts are connefted to the 
 edges of the Larynx, and its fides are covered by the great Blood- 
 veflels of the Neck. 
 
 The fore-part of the Pharynx is formed by a Membrane com- 
 mon to it and to the back-part of the Larynx. 
 
 Behind, it lies flat upon the Cervical Vertebrae, and upon the 
 Mufcles which cover the fore-parts of the fides of thefe Verte- 
 brae. 
 
 It has feveral Openings by which it communicates with neigh- 
 bouring Cavities. 
 
 Two of thefe lead upwards and forwards by the pofferior 
 Nares into the Nofe ; — two go laterally by the Euftachian Tubes 
 to the Ears; — one pafles forwards through the large opening, 
 termed Fauces, or Top of the Throat, to the Mouth one goes 
 downwards and forwards, through the Larynx and Trachea, to 
 the Lungs : — and another direftly downwards by the Efophagvis 
 to the Stomach. 
 
 The Pharynx is fu-rrounded by a loofe Cellular Subftance, and 
 confifts of different Layers of Mufcles, called Conjlriftores Pha- 
 ryngis, which have been already defcribed. 
 
 On the inner fide, it is lined by the continuation of the Mem- 
 brane of the Mouth, which is perforated by the Duffs of nume- 
 rous Glands, for the fecxetion of Mucus, 
 
64 
 
 The lower end of the Pharynx, oppofite to the under edge of 
 the Cricoid Cartilage, defcribes a complete Circle, which 
 forms the beginning of the Efophagus. 
 
 The Pharynx is fupplied with Blood by the Pharyngeal 
 Branches, which come direftly or indireftly from the External 
 Carotids. It returns its blood to both Jugular Veint.— Its nerves 
 are from the Eighth Pair. — - 
 
 The Ufe of the Pharynx is, — to receive the Aliments from the 
 Mouth, and by the aClion of its Mufcles to convey them to the 
 Eiophagus. It mufti ikewifeaflt ft in the modification of the Voice. 
 
 Larynx. 
 
 The Larynx, Co called from its being the principal Organ of 
 Voice, is fituated at the upper and fore-part of the Neck imme- 
 diately under the Os Hyoides, which is placed at the root of the 
 Tongue. 
 
 It is compofed of Cartilages and Mufcles, Ligaments, Mem- 
 branes, and Mucous Glands; and is connected above to the 
 Tongue and Os Hyoides, and behind to the Pharynx. 
 
 The Cartilages of the Larynx are generally contidered as being 
 five in number, though, belides thefe, fome choofe to enumerate 
 fmall Projections which are connected with them. 
 
 The Five Cartilages are,— the Thyroid , the Cricoid , the Two 
 Arytenoid , and the Epiglottis. 
 
 The Thyroid, Scutiform, or Sbield-like Cartilage, is placed at 
 the upper and fore-part of the Larynx, and is the larged: of the 
 whole. 
 
 When fpread out, it is of an oblong fhape, but, in the natu- 
 ral fituation, it confids of two lateral Wings or Portions, of a 
 quadrangular form, uniting before in a longitudinal angle, 
 which can be readily felt in the fore-part of the Throat, and 
 which, from its projecting more in Men than in Women, has 
 obtained the name of Pomum Ad ami. 
 
 The uppet part of the angle is formed into a Notch, from 
 which, and from the upper edge of the Cartilage in general, a 
 broad Ligament afcends, to fix it to the under-part ot the Os 
 Hyoides. 
 
 From the poderior coi ners four proceffes projeCt, called Cornua, 
 two of which termed Superior, are long, and alcend to be joined 
 by round Ligaments to the extremities of the Cornua of the Os 
 Hyoides. 
 
 In the middle of thefe Ligaments, one or two fmall Cartilagi- 
 nous, or even Offeous Subdances, are frequently found. 
 
 The other two Cornua, called Infeiior, 'are fhorter than tne 
 Superior, and curved backwards, to be fixed to the Tides of the 
 Cricoid Cartilage. 
 
 The Thyroid Cartilage ferves for the protection of the other 
 Cartilages, and, along with the Os Hyoides, preferves the Pal-, 
 •■age open, for the tranfmiffion of the Food to the Stomach. 
 
bo 
 
 The Cricoid, or Annular, or Ring-like, Cartilage, is placed 
 below, and likewife behind the Thyroid, and like it, may be 
 readily felt in the fore-part of the Throat. 
 
 It is narrow before, where it lies under the Thyroid Cartilage, 
 and thick, broad and ftrong polferiorly, where it is placed be- 
 hind that Cartilage. 
 
 Its Pofterior Surface is divided by a Ridge into two lateral Ca- 
 vities, for the reception of the pofterior Cricoarytenoid Muf- 
 cles. 
 
 Its under edge is horizontal, and fixed to the beginning, or 
 firft Cartilage of the Trachea. 
 
 The upper edge Hants conliderably, and has its anterior nar- 
 row part fixed to the under edge of the Thyroid Cartilage. 
 
 It has four fmall Articular Surfaces, with diftinft Capfular 
 Ligaments, of which two are placed above, for he articulation 
 of the Arytenoid Cartilages, and two at the under and lateral 
 parts, for the connexion of the iuferior Cornua of the Thyroid 
 Cartilage. - 
 
 The Cricoid Cartilage forms part of the general Tube of the 
 Trachea, conftitutes the Bale of the Larynx, and gives a firm 
 fupport to the Arytenoid Cartilages. 
 
 The two Arytenoid Cartilages, named from a fuppofed refern- 
 blance to an Ewer, or Drinking- cup of the Ancients, are much 
 fmalier than the other Cartilages, and are placed upon the up- 
 per pofte ior, and lateral parts of the Ciicoid Cartilage, at a 
 fmall di fiance front each other. 
 
 They are of a triangular form, and a little twifted, and are 
 bent back, fo as to have a broad concave Surface belt nd. 
 
 Their upper extremities aie turned towards each other, and are 
 confidered by feme Authors as diftindl Cartilages. 
 
 Their Baies are broad and hollow, where they are articulated 
 by Capfular Ligaments with the Cricoid Cartilage, upon which 
 they are moved in different directions, by the aftion of vari- 
 ous Myfcles. 
 
 They are connefled to each other, and to the adjacent Cartila- 
 ges, by different Mul'cles and Ligaments. 
 
 The Arytenoid Cartilages form a part of the opening called 
 Glottis, and give attachment ,o its Ligaments. 
 
 The Epiglottis, obtaining its name from its fituation above, the 
 Glottis, is of an oval form when furrounded by its Ligaments 
 and Membranes, but, when divefted of thelb, it is found to be 
 narrow below, broad above, and rounded at its upper extre- 
 mity. 
 
 It is convex towards the Tongue, and concave towards the 
 Glottis, with its point reflected a little forwards. 
 
 It is placed behind the upper part of the Thyroid Cartilage, is 
 fituated obliquely over the Glottis, and may be fesn and examin- 
 ed by preffing down the root of the Tongue, 
 
 Yoc.. U. F 2 
 
66 
 
 Its under end is fixed by a broad and fiiort Ligament to the mid- 
 dle Notch of the T hyroid Cartilage, and by two lateral Liga- 
 ments to the whole length of the Arytenoid Cartilages. 
 
 It is fixed to the roots of the Os Hyoides and Tongue by ano- 
 ther Ligament, which is a doubling of the inner Membrane 
 running along the middle of its anterior Surface, and forming the 
 Lranum Epiglottidis. 
 
 It is very elaftic, and is much more pliable than the other Car- 
 tilages, being of a Cartilago ligamentous nature. 
 
 It is found to have a number o f Fiffures, in which Lacuna are 
 placed, and to be perforated by numerous Foramina , which are 
 the Mouths of fo many Mucous Follicles, and which are in a 
 great meafure concealed by the Membrane which covers it. 
 
 It breaks the current of the Air coming from the Mouth and 
 Nofe, and prevents it from rufhing too forcibly into the Cavity 
 of the Lungs. — Preffed and drawn down by the Tongue and 
 by fmal! Mufcles, it defends the Glottis, and flints it com- 
 pletely in the time of fwallowing. — After theaffion of fwallow- 
 tng, it is railed bv its own elafticity, and by the root of the 
 Ton gue to which it is fixed, returning to its former p’ fition. 
 
 Ligaments of the Glottis. — From the fore-part of the body of 
 Each of the Arytenoid Cartilages, a Ligamentous Cord pafles hori- 
 zontally forwards, to be fixed by its other extremity to the iniide 
 of the anterior angle of the Thyroid Cartilage. 
 
 The opening formed between tbel'e Ligaments is called Glottis, 
 from the Greek : It is alfo called Mouth of the Larynx, and 
 Rima Glotlidis, and is of a triangular figure, the Ligaments 
 being at a greater difiance behind than at their anterior extre- 
 mity. 
 
 Under thefe.two Ligaments there are two others, larger and 
 more diftinft than the former and whicn are commonly confidered 
 as the proper Ligaments of the Glottis. They arife from the Bale 
 of tnc Arytenoid Cartilages, and run in the fame direflion with 
 the former, to be fixed alfo to the Thyroid Cartilage. 
 
 In the Interftice of the Superior and Inferior Ligaments, on 
 each fide there is a Fifure, which leads to a fmall Membranous 
 Cavity or Depreftion, with its bottom turned outwards. 
 
 Thcfe are the Ventricles of the Larynx of Galen. — They arc 
 chiefly formed by the inner Membrane of the Larynx. 
 
 They differ in fize in different people, have Mucous Follicles 
 opening into them, and are found to be ferviceable in the modula- 
 tion of the Voice. 
 
 On the anterior Surface of the Arytenoid Cartilages, there is a 
 fmall Depreffion fi 1 led by a Glandular Body, which not only 
 covers the fore-part of thefe Cartilages, but is continued over the 
 poflerior extremity of he Ligaments of the Glottis. 
 
 The Arytenoid Glands are larger in fome fubjeffs than in others. 
 They were difeovered, and are particularly deferibed and deline- 
 ate, by Morgagni. 
 
67 
 
 The Ligaments which connect the Epiglottis to the Notch of 
 the Thyroid Cartilage, and to the under fide of the Os Hyoules, 
 and one which ties theBafe of the Os Hyoides, form a triangular 
 J pace , which is alio occupied by Cellular Sublfance and by Mu- 
 cous Glands. 
 
 The Cavity of the Larynx is lined by a membrane which is 
 extremely irritable, and is every where perforated by the Mouths 
 of fmall Mucous Glands, for the purpofe of moiftening it. 
 
 The Larynx has a number of Mulcles, for its different mo- 
 tions; all of which have been already defcribed. 
 
 Tile Arteries of the Larynx are the two fuperior Laryngeals, 
 which come from the External Carotids, and the two inferior 
 Laryngeals, which are fen t off from the Subclavian Arteries. 
 
 The Veins return to the External Jugulars. 
 
 The Ner-ves are chiefly the fuperior and inferior Laryngeals, 
 which are branches of the Eighth Pair. 
 
 The Larynx ferves the purpofe of Refpiration, forms and mo- 
 dulates the Voice, and is alfo ufeful in Deglutition. 
 
 It is the principal Organ of Voice;— for, if a hole be made in 
 the Trachea, and the paflage of the Larynx flopped, the Air 
 efcapes by that opening without producing Voice. 
 
 Voice is formed by the Air, in its paflage through the Glottis, 
 ailing upon the Ligaments of the Glottis and Cartilages of the 
 Larynx and Trachea, and thus producing a Tremour; — and is 
 different in different perfons, according to the Form and Structure 
 of the Larynx. 
 
 The ftrength of Voice is in proportion to the quantity of Air 
 expired, and the narrownefs of the Glottis. 
 
 A Tone is acute in proportion to the tenfion of the parts of- 
 the Laiynff and Trachea in general, and of the Ligaments of the 
 Glottis in particular. 
 
 A Tone is grave in proportion to the reverfe of the above. 
 
 Speech is performed chiefly by the different parts of the Mouth, 
 affifted by the Cavity of the Nofe, — the Larynx moving only in 
 a fmall degree. 
 
 When the Air pafles through the Larynx without producing a 
 Tremour it occaftons a Whifper. 
 
 When a perfon fpeak during infpiration, the voice is thereby 
 very materially altered ; and, by practice, may be made to ap- 
 pear as coming from other places than the mouth cf the fpeaker ; 
 as ts the cafe with thole who cal) themfelves Ventriloquijis. 
 
OF THE THORAX. 
 
 The Thorax, or Breajl, extends from the neck to the Dia- 
 phragm, and is divided into External and Internal Parts. 
 
 EXTERNAL PARTS OF THE THORAX. 
 
 The External Parts of the Thorax, befides the common In- 
 teguments and Mammas, are, 
 
 The Mufcles, confiding of the Peclorales, Subclavii , and un- 
 der end of the Platyfma Moyodcs on each fide, which are fituate'd 
 anteriorly. 
 
 The Serati Magni, whreli are placed laterally. 
 
 The Trapzii, Latiffitm Dor/i, and numerous other Mufcles on 
 the Rack, which are placed pofleriorly. 
 
 The Intercofrales and Sterno-Cojlales, which are fituated- the 
 former between, and the latter on the inner fide of the Ribs. 
 
 The Bones, confiding of Sternum, Ribs, and Dorfal Vertebra. 
 —All thefe Parts, excepting the Mammae, have been already 
 defcribed. 
 
 MAMM2E. 
 
 The Mamma are two Glandular Bodies, of a circular form, 
 fituated on the anterior, and a little towards the lateral parts of 
 the Thorax, adhering loofely by Cellular Subftance to the Sur- 
 face of the large Pt&oral Mufcies. 
 
 The term Mamma is peculiar to the Breads of Women. — In 
 Men' thefe parts are called Mammilla ; — and in the Brute-kind, 
 XJber# . 
 
 In the Ape, and a few other animals, they are placed, as in 
 the Human body, upon the Thorax , — but, in the generality of 
 Quadrupeds, they are fituated under the Abdomen. 
 
 The common number of the Mammae, in the Human fpecies, 
 is well known to be two. — Bartholin E, however, mentions the 
 cafe of a Woman, who had two Mammae on the left fide, and 
 one on the right; and another, where there were two on each 
 fide. 
 
 Dr. Vaughan narrates the cafe of a Woman he has examined, 
 who has a fupernumerary Nipple, at the under fide of the right 
 Mamma, from winch milk flowed when the central one was 
 preffed, and vice verfa. 
 
6D 
 
 'The Mamma? vary in fize in different Women, and in the 
 fame Women at different periods of life. 
 
 In Girls, previous to the age of Puberty, they are remarkably 
 fma )L 
 
 About the age of fourteen, at which time the Meries, in 
 this climate, moft commonly begin to appear, they evolve and 
 become prominent. 
 
 During Geftation they increafe in fize, and foon after Delivery 
 they arrive at their greateft extent. 
 
 After the age of forty-five, or from that to fifty, — tire period 
 when the Mtsnfes generally difappear, they decreafe in fize, and 
 become foft, pendulous, and flaccid. 
 
 Under the Skin, there is a large quantity of Fat which confti- 
 tutes a confrderable portion of the bulk of the Mamma, And de- 
 fends the Glandular Part, and is not found to pais into, or com- 
 municate with, the Ladtiferous Dudfs. 
 
 The Glandular Part of the Mamma is of n wliitifh colour 
 of the Conglomerate kind, and therefore irregular in its Sub- 
 ftance. 
 
 It is ccmpofed of a number of fmaller Mafles or Glands, which 
 are aifo feparated by Fat; and thefe again are divided into 
 ftill fmaller parts, in which the Milk is originally fecreted or 
 formed. 
 
 Near the centre of the Mamma, is the Papilla or Nipple, 
 ■which is of a Cylindrical form, and of a redder colour than the 
 reft of the Skin of the Breaft. 
 
 It is of different fizes in different ages and conftitutions, and is 
 always larger in the time of Geftation, or of Nurfing. 
 
 It is capable of diftention from titillation, or when influenced 
 by the paffions of the Mind. 
 
 It is compofed of a tough Cellular or Ligamentous Suhjlance , 
 ■which inclofes the Ladliferous Tubes, and which is fo elaftic, 
 t hat after the part is drawn out or diftended, it readily recovers 
 its former dimenfion, when the caufe of diftenfion has ceafed to 
 adt. 
 
 Upon the Apex of the Nipple, the Orifices of the Ladfiferous 
 Dudls appear and are of the lame number with thole which enter 
 its Bale. 
 
 Around the Nipple, there is a Circle or Dijk, called Areola, 
 — of a different colour from the reft of the Skin of the Breaft. 
 
 This Difk, however, varies in colour at different times of life, 
 being florid in young Girls, of a pale-brown in Women a lit- 
 tle more advanced in life, and in old age, of a livid, and dull 
 colour. 
 
 During Pregnancy, it is of a darker colour than at other times, 
 in confequence of a change which takes place in the Corpus Mu. 
 cofum which forms it. 
 
1 0 
 
 k 
 
 Under the Skin of the Areola, there are numerous Sebaceous 
 Glands, or Follicles, the Orifices of which dilcharge an oily Mu- 
 cin, to defend the N'pple and Areola around it. 
 
 The Arteries of the Mamma are partly from the Internal, and 
 partly from the External Mammaries or Thoiacics, the former 
 of which are lent oft' from the Subclavian, and the latter from the 
 Axillary Artery, — the Branches entering the M inima at many 
 different places. 
 
 The Veins accompany the Arteries, and are diftinguilhed by 
 the fame names. 
 
 The Abforbenis of the Mamma are alfo numerous, the greater 
 part of which pafs through the Axillary Glands, others penetrate 
 the Interfaces of the Ribs, near the Sternum, and enter the 
 Glands which belong to the Internal Mammary Veffels. 
 
 The Nerajes are chiefly from the Axillary Plexus, a few 
 Branches being alfo fenc off from the Intercoftals. 
 
 From the extremities of the Arteries in the Subftance of the 
 Mamma, numberlefs Tubes arife, called DuFlus or Tubuli Lac- 
 tiferi, which gradually unite into Trunks, and run in a radiated 
 manner towards the root of the Nipple. 
 
 They become grea; ly enlarged in the time of Suckling, and 
 ferve as Refervoirs in which the Milk is contained. 
 
 The Lactiferous DuCfs are accompanied, in the Subftance of 
 the Mamma, by a tough white elc.Jlic Subjlance, which follows 
 them to the Nipple. 
 
 At the root of the Nipple, they become contracted, and are 
 there from Twelve to Eighteen in number. 
 
 Either from the want of uniformity, however, with refpeft to 
 their number in different fubjeCts, or from the difficulty of per- 
 ceiving them, they have been varioufly eftimated by different 
 Authors. 
 
 Near the root of the Nipple, they have been fuppofed by Dr. 
 Meckel, to form a circle of communication; — but this li3S 
 been afenbed by ft 11 later Anatomilts, to a laceration of Veffels j 
 and numerous preparations and experiments, — particularly that 
 of throwing in an injeClion at one Duff, and finding that it fills 
 one part only of the Mamma, without returning by any other 
 Du6f, — teem l’ufficiently to indicate, that there is no i'uch circu- 
 lar communication. 
 
 In the Subftance of the Nipple, the La&iferous Tubes are at 
 a little diftance from each other, and are coiled up in fuch a 
 manner, that the fpontaneous flow of the Milk is prevented, un- 
 iefs it be accumulated in a large quantity. 
 
 But when the Nipple is drawn out and extended, — as by the 
 application of the Child’s Mouth, — the DuCts become ftraight 
 and parallel to each other, fo as to allow an uninterrupted flow 
 of the Milk. 
 
71 
 
 After the a£lion of Sucking, the Nipple, and of conftquence 
 its Du£ts, immediately recover their former fituation. 
 
 Sometimes one or more of the La&i'ferous Dufts terminate 
 upon the Surface of the Areola, from which, Morgagni fup- 
 pofed, that the Glands there were of the Lactiferous kind. 
 
 In Children of both fexes, the Mammae are merely Cutaneous 
 Tubercles, and at the time of birth contain a Milky-like Fluid, 
 which can be readily fqueez- d out. 
 
 This Fluid commonly difappears a fhort time after Birth 
 but there are various examples on record, where Milk has been 
 brought to the Breads, both of young G lismnd old Women, by 
 the frequent application of a Child to the Nipples, and where 
 there was no caufe for fufpicion of Impregnation be ng prelent. 
 Nor are indances awanting of Miik being brought to the Mam- 
 millae of Men, by the fame application. 
 
 The Mamma; add much to the ornament of the perfon, but 
 lerve in particular for furn filing noui ifhment to the Child, which 
 is conveyed to it through the medium of the Nipple. 
 
 The Secretion begins foon after Delivery, and continues to 
 flow for many months, and even for feme years, if the Woman 
 fuckle her Ch'ld ; and the more frequently the Milk is extra&ed, 
 the greater is the quantity received in a given time. 
 
 The operation of Sucking depends upon the principles of the 
 Air-pump.— The child embraces the Nipple clofely with its Lips, 
 which prevents the external Air from entering, draws the Dufls 
 to a draight line, and prepares a fpace for the Milk, which is 
 forced from the Bread by the preffure of the Atmofphere, and 
 dows to the Mouth in the manner a Fluid follows the Piftern of a 
 common Pump or Syringe. 
 
 INTERNAL PARTS OF THE THORAX. 
 
 The Mammae and Mufcles, covering the fore and lateral parts 
 of the Thorax, being turned afide, and the Ribs afterwards cut 
 from the Sternum and turned back, the Internal Parts of the 
 Thorax are brought into-view. 
 
 They confid of ihe Pleura, which lines the Thorax the 
 MediaJUnum, which divides it into right and left Cavities, and 
 contains feveral Veflels, Nerves, &c. between its Layers the 
 Pericardium and Heart, which occupy the middle, — and the 
 Lungs, which furround the Heart, and fill the greater part of the 
 Thorax. 
 
 The Pleura. 
 
 The Pleura is a Membrane of considerable drength, which 
 lines the inner fide of the Thorax, and covers the mod of its 
 contents. 
 
 Its External Surface is Cellular, and adheres clofely to the 
 parts which furround it, 
 
 9 
 
72 
 
 Its Internal Surface is fmooth and polijhed, being moiftened by 
 a Serous Fluid, which exfudes from its Arteries. 
 
 It is divided into two lateral Sacs or Pleura , the form of which 
 covrefponds exaftly with that of the furrounding Bones of the 
 Thorax. 
 
 The Pleurae adhere to the Periofteum of the Ribs, line the In- 
 tercoftal and Sterno Coftal Mufcles, the Sternum, and Dorfal 
 Vertebrae, and cover the Pericardium, Lungs, and Lateral or 
 Flclhy parts of the Diaphragm. 
 
 Behind the Sternum, the Pleurae are contiguous to each other, 
 and form a Partition called Mediajlinum, which extends between 
 the Sternum and Vertebrae, but is intercepted by the Heart and 
 Root of the Lungs, and divides the Thorax into two diftinft 
 Cavities, which have no communication with each other. 
 
 The Arteries of the Pleura are from thofe of the adjacent parts, 
 viz. from the Intercoftal, Mammaries, Diaphragmatics, Bron- 
 chial, and Efophageal. 
 
 The Veins, which return the Blood, accompany the Arteries, 
 and are dittinguiflied by the fame names. 
 
 The Nerves are from the Intercoftals and Diaphragmatics, but 
 too fmall to be traced without difficulty ; and the Membrane it- 
 felf is not obferved to poflefs much fenlibility in the found un- 
 inflamed ftate. 
 
 The Pleura ferves to render the in fide of the Thorax fmooth, 
 for the eafy motion of the contiguous parts, to divide it into Ca- 
 vities, and to (Lengthen the containing and contained parts of 
 the Thorax. 
 
 Mediastinum. 
 
 The Mediajlinum , fo named from its fituation in the middle of 
 the Thorax, is formed by a reflexion of the Pleura, and is of 
 courfe double. — It contains between its Layers a confiderable 
 quantity of Cellular Subftance, by which they are united. 
 
 It is divided into Anterior and Pojlerior Mediaftinum, the for- 
 mer of which is fituated at the fore, and the latter at the back- 
 part tff the Thorax. 
 
 The Anterior MedvaJUnutn is conne&ed before, to the Ster- 
 num ; and behind, to the Pericardium and large Veflels of the 
 Heart. 
 
 The two Layers of the Anterior Mediaftinum ar« clofely ap- 
 plied to each other, excepting at the upper-part of the Thorax, 
 where they are feparated by the remains of the 'Ihymus Gland. 
 
 At the upper-part of the Thorax, it lies exaftly behind the 
 middle of the Sternum ; but in its defcent, it inclines gradually 
 to the left edge of that Bone. 
 
 In confequence of its obliquity, a pointed inftrumerrt, puffier? 
 through the centre of the Sternum, is generally found to pafs 
 into the right Cavity of the Thorax. 
 
T6 
 
 Frequent deviations, however, from this general rule, have been 
 met with. — In particular, Lieutaud and Sabatier, relate fe- 
 veral inftances where the Anterior Mediaftinum was found to 
 delcend along the middle of the Sternum; and others, though 
 rare, where it defcended even to the right hde of this Bone. 
 
 The Pofterior Mediaftinum reaches from the root of the Lungs 
 and back-part of the Heart, to the Dorfal Vertebrae. 
 
 Between the Layers of the Pofterior Mediaftinum, a triangu- 
 lar ftpace is formed, in which are fituated the under end of the 
 Trachea, the Efophagus, the Ao.ta Defcendens, the Vena Azy- 
 gos, and Thoracic Du£t, wth the Eighth Pair of Nerves. 
 
 The Blood-vejj'sls of the Medaftinum are from thofe of the 
 neighbouring parts : — The Anterior Mediaftinum is l'upplied by 
 Branches from the Subclavian, Internal Mammaries, and Dia- 
 phragmatic;., — and the Pofterior Mediaftinum, by Branches from 
 the Intercoftals and Elbphageals. 
 
 The Feins accompany the Arteries, and have the fame names. 
 
 The Mediaftinum divides the Thorax into two Cavities, fup- 
 poi ts its general Contents, hinders one Lung from prefilng upon 
 the other, when the peifon lies on his fide, and prevents Fluids, 
 — whLh, in coniequence of acc der.t or difeafe, may be contain- 
 ed in the Cavitj of the Thorax, — from palling from one fide to 
 the other. 
 
 Pericardium. 
 
 The Pericardium, Sac, or Capfule of the Heart, is one of the 
 itrongeft Membranes of the Body, and its fize fuch as to be pro- 
 perly adapted to that of the Heart, which it contains. 
 
 It is formed of tnuo Layers, the External of which is a conti- 
 nuation of the Anterior Mediaftinum, which afterwards paffes to 
 the Lungs and lateral parts of the Diaphragm. 
 
 The Internal Layer is l'mooth, tendinous-like, and polilhed on 
 its inner Surface, and is ftronger than the other. 
 
 It adheres fo firmly to the Tendinous part of the Diaphragm, 
 as not to be l'eparatcd from it without much difficulty. 
 
 The Pericardium extends a confiderable way beyond the Bafe 
 of the Heart, and includes the large Blood- velfels," as far as the 
 roots of their firft principal Branches, in coniequence of which 
 it forms leveral angles, which have been termed Cornua of the 
 Pericardium. 
 
 While the External Layer is reflected to cover the parts which 
 furround it, ihe inner one is aifo reffefted, firft over the roots of 
 the large Blood- veffels, and then over the Heart, to form its 
 proper covering, in the fame manner the Tunica ConjumStiva is 
 reflected from the Eye- lids to cover the fore-part of the Eye. 
 
 From the ends of the Extreme Arteries, upon its Surface, a 
 Fluid, called Liquor Pericardii, is difcharged, by which it is lu- 
 bricated, and the efte&s of Fri&ion diminilhed. 
 
 Vox. II. G 
 
The Liquor Pericardii is commonly found, after death, in the 
 quantity of a few drachms, though not unfrequently of one or 
 .two ounces. 
 
 Its colour is redder in a young iubje£I, than in a perfon ad- 
 vanced in life, in whom it becomes paler, or more of a ftraw- 
 colour. 
 
 The Arteries of the fore-part of the Pericardium are from the 
 Internal Mammaries and Biaphragmaties ; thofe of its fore-part 
 from the Bronchial and El'ophageal. 
 
 The Veins correfpond with the Arteries, and have the fame 
 name. 
 
 The Ufe of the Pericardium is, to preferve the Heart in fitu, 
 .to defend it from being injured by the parts which furround it, 
 and to rtftrain its inordinate motions. 
 
 OF THE HEART. 
 
 TitE fleart is a hollow Mufcle, divided into different Cavi- 
 ties, and 'inclofed in the Pericardium. 
 
 It is fituated in the Cavity of the Thorax, behind the Sternum, 
 fcetween the Right and Left Lungs. 
 
 It is of a Conical figure, flattened at one fide, and is divided 
 into Bafe, Body, and Apex., with a Superior and Inferior Surface, 
 and a Right and l.ejt Margin. 
 
 The Bafe is placed backwards next the Spine, while the Body 
 and Apex are turned forwards, anil obliquely over to the left 
 fide. 
 
 In Quadrupeds, the Heart is placed upon a line with the Ster- 
 num, the point only touching the Diaphragm : — In the Human 
 Body, the Apex, or Point of the Heart, is but little lower than 
 the Bafe, and projects between the two lobes of the left Lung, 
 Beh'nd the Cartilages of the Fifth and Sixth True Ribs of the 
 left Side, or a little below the left Nipple, where the Pulfation 
 may be felt. — The fituation, however, vai ies a little, according 
 to the pofition of the Body, and ftate of Refpiration. 
 
 Though this be the common fituation of the Heart, a few rar* 
 3nd fingular inffances have occurred, where it has been found to 
 occupy the right fide of the Thorax; and a difplacement has 
 fometimes happened, in confcquence of different kirds of tu- 
 mours m tire left fide of the Thorax. 
 
 The Superior or Anterior Surface of the Heart is convex, and 
 is oppofed to the Pofterior Surface of the Sternum, the anterior 
 edges of the Lungs intervening. 
 
 The Inferior or Poferior Surface is flat, and refrs upon, the 
 Tendon of the Diaphragm, which fupports it; the Heart is not 
 
much affefted, however, by the motions of that Mufcle in time 
 of Refpiiation, its Tendon moving only in a fmall degree. 
 
 The right tide of the Body of the Heart is fharp, and is cal- 
 led Margo Acuius. 
 
 The left tide of the Body of the Heart is round, and is termed' 
 Margo ObtufuS. 
 
 rire Bale is formed of a right and left Auricle , and the Body 
 of a right and left Ventricle. 
 
 When the Heart is defended, the right Auricle, and part of the 
 cori efponding Ventricle, occupy the right, and the relt of the 
 Heart the left Cavity of the Thorax. 
 
 The Heart is connefted above and behind to the upper and 
 back-part of the Thorax, through the medium of the great Vef- 
 fels wh ch go into, or pal's out from it. 
 
 The- other parts of the Heart are free, be. ng merely contigu- 
 ous to .he inlhle-of the Pericardium. 
 
 TheEx.emal Surface ef the Heart is covered with a thin 
 frnooth Membranous Coat , which is a retleftion of the inner Layer 
 of the Pericardium, and which gives additional ftrength to its 
 Flclhy Fib es. 
 
 Between the Coat and Subftance of the Heart, there is com- 
 monly a confiderable quantity or Fat, which lubricates it, and 
 ■facil tales its motions. 
 
 The Subdance of the Heai t con lifts of Mufcular Fibres, firm 
 and more ciolely connected than the generality of Fibres of Mul- 
 cles in otlver parts of the Body. 
 
 The Fibres run in different directions, longitudinal and tratif- 
 verfe, but molt of them oblique. 
 
 Many of them run over the Po>nt of the Heart from one Sur- 
 face to the other, and the whole lo much twilled and folded, and 
 ib varioufly intermixed, as to be difficult to be unravelled or de- 
 feribed : — In general, however, their couife is l’ucli as to leffen 
 the Cavities of the Heart in all their dimensions. 
 
 The Cavities of the Heart are lined wth a Membrane extreme- 
 ly thin, but denfe and ftrong, to defend them againtt the pref- 
 fure of the Blood. 
 
 The Heart is formed of an anterior or right and a poferior or 
 left hde, or of a right and lejt Hea t . j fined together by a Par- 
 tition, which prevents the two fides from having any d left com- 
 munication with each other. — The lenns Right and Letr, how- 
 ever, are more applicable to the Heai t of the Quadruped, and 
 thofe of Anterior and Pofterior to the Human Heart. 
 
 Each ; de of the Heart is fui milled w.th a let of Veins, with 
 an Auricle, a Ventricle, and an Artery, and alio with two lets of 
 Valves, — one between the Auricle and Ventricle, the other be- 
 tween the Ventricle and Artery. 
 
 At the right fide of the Heart are two Veins, ca’letl horn their 
 large fize Vena Cava f the one Superior , the other Inferior. 
 
76 
 
 The Superior Vena Cava, called alfo Vena Cava Defcendens , 
 returns the Blood from the upper parts of the Body; and the 
 Inferior Vena Cava, termed likewise Afcendens , returns it from 
 the lower parts ; and both terminate in the right Auricle. It is 
 prevented from returning by the fullnefs of the Veins, and by 
 the preffure of the Blood a tergo. 
 
 The Auricle is fituated upon the right, and partly upon the 
 back-part of the Heart, and is divided into the right Sinus Veno- 
 fus and proper Auricle. 
 
 The Sinus Venofus is formed by the union of the two Vena? 
 Cavae, which i'weil out towards the anterior and left fide. It is 
 notched at its anterior edge, is a Mufcular Bag of confideiflbie 
 ftrength, and is unifot m and fmooth, both upon it* outer and 
 inner Surface. 
 
 At the upper and left fide of the Sinus, is the projection or 
 Appendix, teimed Proper Auricle, from its fuppofed refemblance 
 to the Ear of a Quadruped : — It is formed by a blind Sac, which 
 is ferrated and notched on its poflerior edge, and convex or 
 rounded on the other, and terminates obliquely in an obtufe 
 point. 
 
 ' The Sinus and proper Auricle form one common Cavity, have 
 no Valve between them, and are therefore filled and emptied at 
 the fame time. 
 
 Where the t.vo Cavities meet in the Hearts of Quadiupeds, 
 there is a Projection feen in the Sinus Venofus, called Tuberculum 
 LOWER!, which is fuppofed to prevent the Blood of the one Ca- 
 va from rufhing upon that of the other, and to diredt it into the 
 Auricle. 
 
 At the meeting of the two Cavae in the Human Heart, an an- 
 gle is formed, which alfo has fiequently got the name of Tuber- 
 culin?] Loweri : — That fubftance, however, is peculiar to the 
 Hearts of Brute-Animals. 
 
 Under tins Angle, or joining of tlie Venae Cava?, there is the 
 Veftige of the foramen Ovale, which, in the Foetus, forms a 
 communication between the right and left Auricles ; but, in the 
 Adult, is filled up by its Membrane, and foims the Ft fa Ova- 
 lis. 
 
 The Foffa Ovalis has thick and ffiong fides, called Column* 
 Foraminis Ova/is, Iftbmus Vieussenii, or Annulus Fofj'a Ova- 
 lis. 
 
 At the left fide of the Mouth of the Inferior Cava, where it 
 joins the Sinus, is the Valve of Eustachius. 
 
 It is in form of a Crefcent, with the convex edge fixed to the 
 union > f the Sinus and Cava, and the concave edge turned ob- 
 liquely upwards, reaching about half way over the Mouth of 
 the Cava. — Its fize and appearance, however, vary much in dif- 
 fident Subje&s. 
 
77 
 
 Its pofterior Cornu is continued with the left fide of the Ifth- 
 mus of the Foramen Ovale ; the other end vanilhes in the oppo- 
 fite fide of the Sinus. 
 
 It is equally ditfinft in the Adult as in the Foetus ; but in the 
 former it is frequently found reticulated, or Cribiiform, which 
 appearance is l'eldom, though fometimes, met with in the latter. 
 
 In the Adult, it is fuppofed to prevent the Blood of the Au- 
 ricle from palling into the Inferior Cava; and in the Foetus, to 
 direft the Blood of the Inferior Cava to the Foramen Ovale. 
 
 Upon the left tide of the Valve of Eustachius, in the under 
 part of the Auricle, s the Orifice or Termination of the g. eat 
 Coronary Vein of the Heart. 
 
 Over the Orifice of this Vein, there is a Semilunar Valve, to 
 prevent the Blood in the Auricle from palling into the Vein. 
 
 The inner fide of the proper Auricle is readily dillinguilhed 
 from the Sinus, by having a number of Columns Carnes, or 
 Flejhy Pillars in it, which, from their fuppoied rei’emblanee to 
 the Teeth of a Comb, fometimes obtain the name of Mufculi 
 Auricula Pechnati. 
 
 The Mufculi Pe&inati have fmalier Columns running in dif- 
 ferent diiv£Vons, giving the whole a reticulated appearance. 
 
 Between the Column* Carneae, are Deprejjions or Furronus, in 
 which the tides of the Auricle are thin, and femi • tranfparent, 
 being chiefly formed by the outer and inner Membrane of the 
 Auricle. 
 
 At the under and left fide of the Sinus Venofus, and oppofite 
 to a Groove, fitilated externally between the Auricle and Ventri- 
 cle, there is a Hols, above an inch in diameter, which opens in- 
 to the upper and right part of the correfponding Ventricle. 
 
 The right Auricle receives the Blood from the Vense Cavas 
 and Coronary Veins, and, by its MufcuUr contra&ion, difchar- 
 ges it into the correfpondmg Ventricle, out of which it is pre- 
 vented from returning oy a Valve, called Tricufpid , placed with- 
 in the Ventricle. 
 
 The Right or Pulmonary Ventricle, is fit ua ted on the fore-fide 
 of the Heart, is of a triangular form, and much thicker and 
 Wronger than the correfponding Auricle. 
 
 it iias many itrong Eminences, Columns, Lacertuii, or Cords, 
 called Colamna Carnes. 
 
 The Columns run in different directions, but the ftrongeft of 
 them longitudinally, and tie or various iizcs, forming fo many 
 diitinft Muicles, which are extremely compaft in their ftruc- 
 ttire, and compofe a beautiful, intricate, and irregular Net- 
 woik. ' 
 
 In general, they adhere through their whole length to each o- 
 ther, or to the fidcs of the Ventricle; but many of them are loofe 
 ;n their middle, and.may be railed by a probe put under them. 
 
 Yoi„ II. G 3 
 
78 
 
 They affift the Ventricle in its SjJlole or contraction, and pre- 
 vent it from bei n oveiftretched in it : Dyajt'le or dilatation, and 
 agitate the Blood in its palfage through the Ventricle. 
 
 They are fuppofed to bring the oppofite Tides of the Ventricle 
 completely together, during its contraction. 
 
 Between the Columnae are many deep Grooves, Pits, 01F0- 
 veae, into all of which the Blood readily enters. 
 
 Around the Paffige, between the Auricle and Ventricle, there 
 is a tendinous Margin or Ring, from the whole edge of which 
 a circular Membrane is fent off, called Valvula Tricufpis, or Tn- 
 glochin, from its having thiee principal points or divisions. 
 
 From the edge of the Tricufpid Valve, many 1’mall round 
 'Tendinous Cords are fent off, of unequal fize. 
 
 The Chorda Tendinea defcend obliquely within the Ventricle, 
 in the fame direction with the Valve from which they arife. 
 
 They are fixed to the extremities of a few ftrong Papillae or 
 Columnae Caineae, which are joined by their other extremites to 
 the comlpondmg fides of the Ventricle. 
 
 The Tricufpid Valve prevents the reflux of the Blood to the 
 Auricle, during the contraction of the Ventricle. 
 
 The Tendons allow the Valve io be puffied back by the Blood, 
 until a Septum or Partition is formed by it at the Mouth of the 
 Ventricle, during the contraction of the latter.— The Papillae, by 
 their contraction, prevent the Valve from going into the Auri- 
 cle. 
 
 The Valve is opened and prefi'ed back by the Blood in its paf- 
 fage from the Auricle to the Ventricle. 
 
 The upper and left fide of the Ventricle becomes fmooth and 
 uniform, and leads to a large Opening, about an inch in diame- 
 ter, which is the Mouth of the Pulmonary Artery. 
 
 The right Ventricle, by its dilatation, receives the Blood from 
 the Auricle, and fends it, by a thong and hidden convuifive 
 contraction, to the Pulmonary Artery, from whence it is pre- 
 vented from returning, by three Valves placed in the Mouth of 
 the Artery. 
 
 The Valves at the Mouth of the Pulmonary Artery are called 
 Valvula Semilunares, or Sigmoidea, from the refemblance of 
 their edges to thofe of a Crefcent. — Two of them are placed in 
 the fore, and one in the back-part of the Artery. 
 
 Each cf them forms a fmall Sac, one edge of which adheres 
 to a third part of the circumference of the infide of the Artery ; 
 the other edge is loofe in the Cavity ot that Veffel, and is fotne- 
 what thicker and ftronger than th# teff of the Valve,— the thick- 
 ened edges ferving as Ligaments to it. 
 
 The loofe edge has a general Curve, divided into tvso fmaller 
 ones, which meet in a point in the middle. 
 
 The Valves are chiefly formed of a doubling or exttnfion of 
 the inner Coat of the Artery. 
 
In the middle point or loofe edge of each of the Valves, there 
 is a fmall hard triangular Granula, of a fomewhat redder colour 
 than the relf of the Valve, called, from its reputed dilcoveries, 
 Corpufculum Au R ant ii, or Corpufculum Morgagni ; or from 
 its rel'emblance in fhape to the Sefamum feed, Corpufculum Sefa- 
 moideum. 
 
 The Corpufcles complete the Valves at the centre of the Arte- 
 ry, and enable them to make, a ftronger reiiftance againfl the 
 B.ood, while the Artery is in a£bon. 
 
 The Semdunar Valves zee. con cave towards. the Artery, convex 
 towards the Ventricle, and, when fliut, their loofe edges are op- 
 pofed to each other, fo as to enable them to form a complete Par- 
 tition between the Ventricle and Artery. 
 
 Oppofite to the Semilunar Valves, the Artery bulges out, and 
 forms three Projections, which have correfponding Pitts or De- 
 preflions within, and are called, from their defcoverer, Sinus 
 Valsalva. 
 
 The Sinufes of Valsalva are of the fame nature w : th thofe Di- 
 latations which are found in the Veins and Lymphatics, between 
 their Tides and Valves ; and, like them, are partly formed by the 
 prefiure of the Fluids upon the tides of the Velfels. 
 
 The Pulmonary Artery receives the Blood from the right 
 Ventricle, and by its contractile power, aflilts the Ventricle in 
 driving it through the Lungs. 
 
 The Semilunar Valves, preffed back by the Blood in the Ar- 
 tery, prevent its return into the Ventricle. 
 
 The Valves are opened again by being driven towards thefides 
 of the Artery by the current of the Blood, upon the next con- 
 traction or ftroke of the Ventricle. 
 
 The Pulmonary Artery pafl'es behind the Sternum, and fepa- 
 rates into right and left Branches, which go to the correfponding 
 parts of the Lungs. 
 
 The two Branches of the Pulmonary Artery, like thofe of the 
 Arteries of he Vifcera in other pans of the large Cavities, fud- 
 denly divide into Itill fmaller Branches. 
 
 From the extreme Arteries of the Lungs, correfponding Veins 
 arife, and are merely the continuation or reflection of the Arte- 
 ries, without any intermediate Cell " or Dilatations. 
 
 The Pulmonary Veins, in the Su-'ftance of the Lungs, srradu- 
 ally unite, and form four principal Trunks , which terminate in, 
 and carry the Blood to the left Auricle. 
 
 Of the Pulmonary Veins, two come from the right, and two 
 from the left lung, and terminate m the correfponding Tides of the 
 left Auricle. 
 
 The left Auricle is confiderably thicker and A: onger than the 
 right, and, like it, is divided into Sinus Veubfus. and proper 
 Auricle, which from one common Cavity without the interven- 
 tion of any Valve. 
 
80 
 
 The left Sinus Venofus, called alfo Sirius PulmQnalis, is turned 
 towards the Spine, is more of a cubic form than the right one j 
 but refenrbles it in the uniformity and fmoothnefs of its outer 
 and inner Surfaces. 
 
 From the fore and left part of the Sinus, the Proper Auricle 
 projects, and forms a diftintf flat Appendix, or Bag, with dif. 
 ferent Curvatures or Indentations upon its edges. 
 
 The inner part of the Proper Auricle is longer, but narrower 
 than that on the right fide , like it, however, it is formed of 
 Columns Carnete, with Furrows between them. 
 
 The Proper Auricle is fomewhat lefs capacious than that on 
 the right fide j but the Smus is as much larger as to tender the 
 two common Cavities of the right and left Auricles nearly 
 equal. 
 
 The two Auricles have a Plefby Septum between them, in which, 
 as has been already mentioned, there is the Foramen O-vale in the 
 Foetus ; — but in the adult the Partition is generally perfefl. 
 
 From the under part of the Sinus Venofus, a PaJJage leads 
 down to the Cavity of the Left Ventricle, and is oppolite to a 
 Grove Celt externally between the Auricle and Ventricle, fimilar 
 to that on the right fide. 
 
 The Left Auricle receives the Blood from the Pulmonary 
 Veins, and by its Mufcular contraction, drives it into the Left 
 Ventricle, from which it is prevented from returning, by a Valve 
 in the Ventricle, called Mitralis. 
 
 The Left Ventricle is lituated in the pofterior and left part of 
 the Heart. 
 
 Its fides are about three times thicker and fronger than thofe of 
 the Right Ventricle, being in proportion to the force required to 
 propel the Blood to the moil remote parts of the Body. 
 
 It is nanower and rounder, but coniider bly longer, both on 
 its External Surface and in its Internal Cavity, than the R : ght 
 Ventricle, and generally defcends fumeway below the other, and 
 forms the Apex cordis, or Point of the Heart. 
 
 The Cavity is commonly defcribed as being lefs than that of 
 the Right Ventricle ; — But the* apparent difference, which takes 
 place after death, is accounted tor with feemii g propriety by fome 
 Authors, — from the left Ventricle being tic ■ c r the me ft part 
 found empty, and the Right one full, and front cite, g: inter de- 
 gree of contraftiiity n die former 
 
 That the capacity of the Cavity cf t! e ripht ami 1- , t dec of 
 the Heart is more nearly equal during lire that after cl ath, or 
 than it is generally fuppofed to be . tv -mv- re. tne ar. earance 
 
 of the Heart of the Human ai.d ;»o of > i ; k nn, ami .torn 
 
 inj flions nto the two Tides of the f.-'iic where the : tree ap- 
 plied is in pro" ition to the relative It re ; cth r i 1 < 
 
 The inner Sm face of the Left Ventricli has h > fame general 
 appeal ance with the Ventricle of the ng. i flue, and only d.fters 
 
SI 
 
 from it in having ns Column* Came* larger, firmer and ftvong- 
 er. 
 
 In the Paffage of communication between the Auricle and 
 Ventricle, there is a Ring, from which a Circular Palms goes 
 off, with all its apparatus fimilar to that between the right Au- 
 ricle and Ventricle, and differing in no reipeft from it in llru&ure 
 and ufe, excepting in being ftronger, and in being divided into 
 two principal portions only. 
 
 This Valve has been fuppofed to bear fome refemblance to a 
 Bijhop's Mitre, from which it has been called Palmula Mitralis. 
 
 One of the portions of this Valve is larger than the other, lies 
 over the Mouth of the Aorta, and is fuppofed to cover it while 
 the Ventricle is a filling. 
 
 The Palmula Mitralis prevents the reflux of the Blood during 
 the cor.traftion of the Ventricle. 
 
 After the coatraction is over, the Valve returns to its former 
 fituation by the impulle of a frelh current of Blood from the Au- 
 ricle. 
 
 Between the Right and Left Ventricle, there is a thick ftrong 
 impervious Partition, wlrch forms a fhare of the general Septum 
 Cordis, and is compofed partly by the wall of the Right, but 
 chiefly by that of the Left Ventricle, the Right being united to 
 the Left, almoft in the form of an Appendix. 
 
 The Partition prevents any dirett communication between the 
 two Ventricles. 
 
 • Oppofite to the outer edge of the Septum, both upon the up- 
 per and under Surfaces of the Heart, there is a Groome in which 
 fome of the principal Trunks cf the Coronary Veflels are fitu- 
 ated. 
 
 At the fore and right fide of the Valvula Mitralis, and behind 
 the beginning of the Pulmonary Artery, there is a round Opening 
 which is the Mouth of .he Aorta, and which is nearly of the 
 lame fize wiih that of the Pulmonary Artery. 
 
 Under this opening, the Surface of the Ventricle becomes 
 fmootb, and equal, having none of the Columnse Came* which 
 are l'een on the other parts of its Cavity. 
 
 The Left Ventricle receives the Blood fent to it from the Au- 
 ricle, and by a contraffion fimiar to, but much ftronger than 
 that of the Right Ventricle, propels it to the Aorta. 
 
 At the Mouth of the Aorta, there are three Semilunar Palmes, 
 with the'r Corpufcula Aur an Tir, perfectly fimilar to thole of the 
 Pulmonary Artery; — but a little ftronger. 
 
 On the outiideof the Semilunar Valves, are the Sinufss of Val - 
 salva, like thofe of the Pulmonary Artery, — but a little more 
 prominent. 
 
 The Semilunar Valves are prefled back by the Blood, and pre- 
 vent its reflux during the contraftion of the Aorta.-— They are 
 
82 
 
 returned towards the Tides of the Aorta, in the fame manner, 
 and from the lame caufe, as in the Pmmonaiy Artery. 
 
 The Aorta paffes upwards from ihe top of the Left Ventricle, 
 and is lituated fit It behind, and then on the right line’' of the 
 Pulmonary Artery, and betwen it and the Superior Cava. 
 
 It bears nearly the lame proportion in thicknefs and Itrength 
 to the Pulmonary Artery, which the Tides of the Left Ventricle 
 do to thole of the Right. 
 
 When the Aorta is about to fend off the full of its large 
 Branches at the top of the Thorax, it is f great fize, and is 
 fometimes called the Large Sinus of Valsalva. 
 
 The Aorta receives me Blood from the Left Ventricle, and by 
 its Muicular contraftiun re-afts upon it, and aflilhi the Ven- 
 tricle in fending it by numberlels Branches through the d ft’erent 
 parts of the Body, from whence it is returned by the Veins to 
 the Rit lit Auricle. 
 
 B.eiides the Blood -veflels already taken notice of, and which 
 are common to the Heart and the red of the Body, the Heart is 
 furn. filed with Veffels peculiar to itlelf, termed Coronary from a 
 Corona which they form upon its fuiiace. 
 
 The Coronary Velfels con lift of two Arteries and one principal 
 Fein, 
 
 The Coronary Arteries arife from the Sin life- , at the Mouth of 
 the Aorta, oppufite to two of the Semilunar Valves. 
 
 One tuns in a Groove between the Right Auricle and Ventri- 
 cle, and fupplies chiefly the right fide of the Heart. 
 
 The other paffes partly between the Left Auricle and Ventri- 
 cle, and partly in the Groove between the Ventricles, on the fore- 
 fide of the Heart,— fupplying the left fide of the Heart, and com- 
 municating wuh the Branches of the other Artery on its upper 
 and under Surfaces. 
 
 The Coronary Arteries are entirely difperftd upon the fubflance 
 of the Heart, and upon the roots of the great Veffeb, forming 
 upon thef’e fume of the minute Blanches, termed Fafa Faforum. 
 
 The Coronary Arteries, from their fituation oppofite to the 
 Valves, have been fuppofed to be filled at a different time from- 
 that of ihe reft of the Aiterious Syftem ; — but from experiment, 
 it Teems now AifRcient ly evident, that the Coronary Veffels have 
 their puliation at the fame inltant with the other Arteries. 
 
 The Coronary Feins return the Blood from their correfponding 
 Arteries : The greater part of them join into a Trunk., called 
 the Great Coronary Fein, which, after making a turn from the 
 left fide, and running between the Left Auricle and Ventrcle, 
 terminates in the under part of the Right Auricle, where it i9 
 covered by its Semilunar Valve. 
 
 Other Coronary Veins, much fmaller than the former, termi- 
 nate in different parts of the right fide of the Heart. 
 
The Abforbents o f the Heart go to the neighbouring Lympha- 
 tic Glands. 
 
 The Nerves are from the great Sympathetics and Eighth Pair. 
 
 With refpedl to the Circulation in general : — The Veins re- 
 turn the Blood from all the different parts of the Body by a flow 
 and equal motion, and without puliation, to the Aui icles, which 
 on account of the quantity and ffimulating quality of the Bicod, 
 contrail fuddenly and at the lame time, and fend it to the Ven- 
 tricles. 
 
 The Ventricles, from the fame caufe which (Emulates the Au- 
 ricles, and from the ffroke they receive from them, contraftcon- 
 vulfively, with a force proportioned to the tliicknefs of their fidesf 
 and fend the Blood to the Arteries.; and, during their contraftion, 
 they are thrown by the dilatating Auricles againft the Ribs, where 
 the ffroke occafioned by the Pull'e of the Heart may be felt. 
 
 The Arteries, by their contradffile power and elafticity, fend 
 the Blood fuddenly to the Veins, through which, by the united 
 force of the Ventricles and Arteries, and iikewife, as is fuppofed 
 by fome, by a contraflile power of the Veins and preffure of the 
 furrounding parts, it is driven again to the Auricles. 
 
 In its coutfe the Blood performs a double Circulation,— -one 
 called the Leffer or that through the Lungs; — the other called 
 the Greater, ®r that through the Body. 
 
 In the former it pafl'es from the Right Ventricle to the Lungs, 
 and returns to the Left Auricle. — In the latter, it goes from the 
 left Ventricle to the different parts of the Body, ana returns to the 
 Right Auricle. 
 
 During this Circulation, the Auricles and Arteries, and the 
 Ventricles and Veins, a<EI in concert, contrafting and dilating at 
 the fame time. 
 
 UTe of the Heart. -The Heart is the centre of the Vafcu- 
 
 lar Syltem, and the principal agent in the Circulation of the 
 Blood. 
 
 The right fide of. ihe Heart receives the Blood, which is con- 
 taminated in paffing through the Body, and fends it to the Lungs, 
 where it is purified through the medium of the Air. 
 
 From the Lungs, ihe Blood, now purified, is returned to the 
 left fide of the Heart to be circulated through all the other parts 
 of the Body, thereby imparting Nourifhment, Growth, and 
 Strength to the general Syftem ; being found all'o to be the fource 
 of Senfibility, Irritability, and Motion, and Iikewife of the Ani- 
 mal Heat. 
 
OF THE LUNGS. 
 
 The Lungs are two foft fpongy bodies, which occupy by much 
 the greater part of the Cavity of the Thorax. 
 
 They completely fill the two bags of the Pleura, and are every 
 where in contatt with the parts adjacent ; no Air intervening be- 
 tween them and the Thorax. 
 
 In figure, they have been compared to that of the Foot of an 
 Ox, with the back part turned forwards or, their fhape cor- 
 refponds exaftly with the infide of the Thoiax, being rounded 
 next the Ribs, hollow towards the Diaphragm, and irregu- 
 larly flattened and depreffed next the Mediaitinum and Heart. 
 
 They are of a reddifh or pink colour in Children, of a light 
 blue or greyifh colour in Adults, and more of a purple and li- 
 vid colour in Old Age, at which period they are alfo oblerved to 
 be tinged with black fpots, proceeding from a matter fecreted in 
 their Subllance. 
 
 They are joined to the Neck, by the Trachea; to the Spine, 
 by the two Layers of the Mediallinum, which ferve them as 
 Ligaments ; and to the Heait, by the Pulmonary VelTels; — the 
 relt of them being free and unconnected, unlefs an adhefion has 
 taken place in confequence of inflammation . 
 
 They are divided into Right and Left Portions, or Lungs, 
 which are feparated from each other by the Heart and Mediaiti- 
 num and which have no communication, excepting through the 
 Medium of the Trachea. 
 
 Each of the Lungs is again divided, into large portions, called 
 Lobes, which facilitates their motion and the dilatations of their 
 Cells. 
 
 Of the fe Lobes, three belong to the Right Lung, correfpond- 
 ing with the larger Bag of the Pleura, and tnxso to the left, be- 
 tween which there is a Notch or Sinus, occupied by the Point of 
 the Heart. 
 
 Each of the Lobes is fubdivided into many fmaller parts, 
 termed Lobules, which are of different lizes, anti of an irregular 
 angular form. 
 
 The Lobules dimlnifh in fize, and degenerate at laft into finall 
 Vefclcs or Cells, which conftitute a large /hare of the Lungs, and 
 •which are merely vifible to the naked Eye. 
 
 The Cells of the Lungs are purely Membranous, of an irregu- 
 lar figure, comprefled and clofely connefted, and have a free 
 communication with each other. 
 
 Between the different Lobes, Lobules, and Cells, a large 
 quantity of common Cellular SubUance, flefldtute of Fat, is in- 
 
85 
 
 tcrpofed, which unites and (Lengthens them, and allows the 
 Bjood-veffe'ls to be minutely dil'peried over them. 
 
 The Cells of :he Lungs have no communication with this, 
 common Cellular Subffanre ; for when Air is blown into it, the 
 Lobules are coinprefled ; but when the - Air is blown in through 
 a Bran.h of the Trache-i, the Cells are again iliffended, and tne 
 Lobules lecover their former dimenuons. 
 
 In the Fee. us, the Cells are. empty and in a collapfed ftate ; 
 — but as icon as Respiration begins, they become diffended, and 
 continue fo during life, and in every ftate of Refpiration, and 
 even in the recently dead Body : — But if an opening be made 
 into the Cavity of the Thorax* whether, in the, living or dead 
 Body, — and the Air in this or in any other way admitted, they 
 immediately co.lapfe by their own weight and e,iaftscitv, the 
 prelfure of the air being then the fa ne on the outer Surface of 
 the Lungs, and inner Surface of the Trachea. 
 
 The Lungs are covered by .two Coats, an External or Com- 
 mon, and an Internal or Proper one. 
 
 The External o. Common Coat is a continuation or reflefljon of 
 the Pleura, is extremely thin, butdenfe, and, like the other parts 
 of tbe Pleura, is found to polfefs little Sepfibiiity, It forms a 
 general covering to the Lungs, but does not enter between their 
 different Lobules. 
 
 The Internal or Proper Coat adheres fo firmly to the former, 
 as to appear to conffitute part of its Subffance. It not only co- 
 vers the Lungs, but infinuates itfelf between their Lobules, and 
 is intimately connected with their Cellular Subffance. 
 
 Befides the Cells, various kinds of VefTels, viz. th tAir-vef- 
 f els or Branches of the Trachea, Blood-'vejJ'els and Ahforbents, to- 
 gether with fmall Branches of Nerves, enter into the compoiition 
 of the Lungs. 
 
 Trachea. 
 
 The Trachea, or Afpera Arteria, fo called from the inequali-' 
 •V of its Surface, and from its conveying Air, begins at the un- 
 der put of the Cricoid Cartilage, and defeends in the fore part 
 ot the Neck, between and behind the Sterno-hyoid and Sterno- 
 thyroid Mufcles. 
 
 From the Neck, it naffes into the Thorax, vfrhere it is fituated 
 between t!ie Layers of the upper-part of the posterior Media- 
 ftsnnnj. 
 
 Behind the Curvature of the Aorta, and oppofite to tlife 1 
 thud Vertebra or the Th rax, the Trachea divides into 'two 
 Lateral Branches, termed Bronchi, from the Greek, one of which 
 goes to the Right, and the other, which is the longer of the two' 
 to the Left Lung. - . . 
 
 Vo L. II. 
 
 H 
 
86 
 
 The Bronchi are divided into Branches, which by degrees be- 
 come fmallei-, and at lad terminate in the Cells of the Lungs, 
 which communicate To freely with each other, that, upon intro- 
 ducing Air into any of thefe Brandies, a large portion of the 
 Lungs may be inflated. 
 
 The Trachea confifts of Cartilaginous Rings, about fixteen or 
 eighteen in number, which give (Length and firmnefs to it, and 
 preierve it conftantly open for the trammiffion of Air. They are 
 incomplete behind, where the Trachea is formed of a foft Elejhy 
 Sub_ftar.ce , which yields to the Efophagus in the time of Deglu- 
 tition. 
 
 Each Cartilage forms a large fegment of a circle, about a line, 
 or one-twelfth of an inch in bre'adch, and one-fourth of a line in 
 thicknels. 
 
 The Cartilages are fituated horizontally, with their edges op- 
 pofed to each ether, fmall fpact s intet veiling between them. 
 
 They are united to each other, by a Ligamentous Subftance, 
 which is lb elaftic, that when the Lungs are taken out of the 
 Body, it draws the Cai tilages cloiely together. 
 
 At the upper end of the Trachea, two or three of the Cartila- 
 ges are frequently joined by an union of Subftance ; but below 
 this, they are perfedly dift nft from each other. 
 
 The beginnings of the Bronchi have the fame kind of Cartila- 
 ges with the Trachea ; but after they enter the Lungs, they are 
 broken into two or three pieces, which go completely round the 
 Bronchi, and are fo conneded to each other, as to keep the Paf- 
 fage open and free from compiefiion. 
 
 The Trachea has feveral Coats entering into its compofition, 
 fomefor (Lengthening it, others for giving it a certain degree of 
 motion, viz. 
 
 A Cellular Coat, which, in the Thorax, is coveted by the Me- 
 diaftinum. 
 
 An Elajlic Ligamentous Coat, which pafles along the Trachea, 
 and alio upon the different Branches in the fubftance of the 
 Lungs, adding much to the elafticity of thefe. 
 
 A Mufcular Coat, placed between the Cartilages, and in the 
 back-part of the Trachea, and coinpofed of Circular Fibres 
 without, and Longitudinal Fibres within ; — the former for 
 ftraitening, the other for (hortening the general Paffage. 
 
 The Longitudinal Fibres arecolleded into bundles, which are 
 diftindly feen through the inner Coat, and may be traced con- 
 siderably farther, in the Subftance of the Lungs, than the Carti- 
 lages. 
 
 The inner fide of the Trachea is lined with a very Cafcular 
 und Irritable Membrane, continued from the Mouth, and form- 
 ing at latt the extreme Branches of the Trachea, which terminate 
 m the Cells of the Lungs. 
 
S7 
 
 The inner Membrane of the Trachea is every where perforated 
 by the Duels of Mucous Glands, and by the Mouths of the Ex- 
 hales:! Arteries, the former pouring out Mucus to lubricate the 
 Lungs, tne other the Vapour which is thrown off in Perfpira- 
 tion. 
 
 Three different kinds of Glands are conneiled with the Tra- 
 chea, — the Thyroid, the Tracheal, and the Bronchial. 
 
 The Thyroid Gland has its name from its connection with the 
 Thyroid Cartilage, though more immediately connected with 
 the Trachea. 
 
 It is a large reddifh mafs, fi uated at the under and fore-part 
 of the Larynx, behind the Sterno-hyoid and Sterno- thyroid 
 Mufcles . 
 
 It has two Lobes placed at the under and lateral parts of the 
 Larynx, del'cending a certain way upon the Trachea and Efo- 
 phagus. 
 
 fhe Lobes are joined by an intermediate portion, which lies 
 acrofs the upper and fore-part of the Trachea, 
 
 Sometimes a Procels from the middle portion afeends between 
 the Sterno-hyoid Mufcles, and is loft behind the Bafe of the Os 
 Hyoides. 
 
 This Gland has a Grandulous appearance within, and a vifeid 
 Liquor is fometimes obferved in it, which has been fuppofed by 
 Sabatier and others, to lubricate the parts in the neighbour- 
 hood. 
 
 It is fupplied with large Blood -veffels, and with feveral 
 Nerves, from thofe of the Larynx ; it is likewife furniflied with 
 numerous Lymphatics, — but no Excretory Du£l has yet been ob- 
 ferv£d to come from it ; nor is its office yet underftood. 
 
 The Tracheal Glands are fmall, but numerous, and of different 
 fizes, furrounding the Mufcular Coat of the Trachea, and its 
 Branches in the Lungs ; the largeft of them are placed in the 
 Flefhy Subftance behind. 
 
 From each of thefe Glands a fmall Du£I iffues, and throws 
 out a Mucus, to defend the inner Surface of tne Trachea from 
 being injured i>y the Air, or by the extraneous particles which it 
 carries along with it. 
 
 The Bronchial Glands are placed in the Cellular Subftance 
 round the under end of the Trachea and roots of the Bronchi, 
 where thefe penetrate into the Subftance of the Lungs. 
 
 They arc of various fizes, from that of the point of the Lit- 
 tle Finger to that of a Millet-feed, and have a bluifh or black 
 colour, correfponding in a great meafure with the colour of the 
 darkeft pails of the Lungs. 
 
 They were formerly confidered by many Authors as fending 
 Fluids to the Trachea, but are now fufficiently known to be entire- 
 
 
83 
 
 iy ef the Lymphatic kind, — the Abforbents of the Lungs paffing 
 through them in their way to the Thoracic Dufl. 
 
 The Trachea is furnifhed with Blood-<vc£els from the Inferior 
 Laiyngeals, and Nerves hem the Recurrents and great Sym- 
 pathetic Pair. 
 
 The Trachea ferves to convey Air into, or out from the Cells 
 of the Lungs, during Relpiration, and to carry off the Peiipir- 
 able Mattel front their Arteries in time of Expiration. 
 
 The Blood- Vejfels tf the Lungs confift of the Pulmonary and 
 Bronchial VeJJ'els ; the one for the general Circulation, the other 
 proper to the Lungs. 
 
 Tlie Pulmonaiy Artery arifes from the top of the Right Ven- 
 tricle, divides, like the Trachea, into Right and Left Branches, 
 which are dilperled through the lubltance of the Lungs. 
 
 The minute Blanches tunning in the common Cellular Sub- 
 ftance, form at lall a Plexus upon the proper Cells, fometimes 
 called Rete Mirabile, and Rete Vafculofum Malpighii, from 
 which that Halitus is derived which is expelled by the Lungs in 
 Expiration. 
 
 The Pulmonary Veins are commonly obfetved to be fmaller in 
 proportion to the correTponding Arteries, than Veins are to Ar- 
 teries in other parts of the Body, which has been fuppofed to be 
 owing to the large quantity of Fluids expired. — They join into 
 four principal Trunks, which terminate in the Left Auricle. 
 
 The Bronchial Arteries arife by tlnee or four fmall Branches, 
 one of which is from the right Superior Intercollal, the reft'from 
 the Trunk of the Aorta. 
 
 They aie dilperled upon the Bronchi and Bronchial Glands, 
 and fubftance of the Lungs in general, and are found to com- 
 municate with the Pulmonary Artery. 
 
 The Bronchial Arteries are fuppofed to ferve for the nourifh- 
 ment of the Lungs and fecretion of the Mucus. 
 
 The Veins return the Blood to the Vena Azygos, and left fu- 
 per'or Intercollal Vein. 
 
 The Lymphatics form a Plexus upon the Surface of the Lurgs : 
 —They communicate fieely with the deep-fcated Abfcrberiis, 
 and pafs through the Bronchial Glands. 
 
 The Nerves of the Lungs are partly from the great Sympathe- 
 tics, but chiefly from the Eighth Pair, and are rather fmall in 
 proportion to the bulk of the organ on which they are dilperled. 
 
 The Lungs ferve the general purpofe of Refpiration, which 
 con fills of Indication and Expiration, or the paflage of the Air 
 inlu or out from the Lungs by the alternate dilatation and con- 
 fiaffion of the Thorax. 
 
 I/ifpiration is. performed in confequence of the Thorax being 
 dilated by the aftion chiefly of the Diaphragm and In ei coital 
 Mufcles ; the Lungs, which are paffive, and in contact with 
 
89 
 
 the Thorax, following it, and the Air rufhing into the Trachea 
 by its own gravity. 
 
 Expiration is performed in confequence of a relaxation of the 
 Mufcles which dilate the Thorax, — of the action of the Abdo- 
 minal and a few other Mufcles, — of the elaftic ty of the C irtila- 
 ges of the Ribs, and likewife of the Lun . s, by which the Cavity 
 of the Thorax is diminifhed, and the Air is expelled from the 
 Lungs. 
 
 Upon the alternate (dates of Infpiration and Expirat'on, de- 
 pend the formation of the Vo ce, the fenfation of Smell, and all 
 the other functions of the Body : but the g eat and principal 
 office of the Lungs, which was formerly fuppofed to be that of 
 cooling the Blood over-heated by friction, is, during Infpda- 
 tion, to receive from the Atmofphere pure At, upon wbicn the 
 principle of heat and life Depends; and, during Expiration, to 
 carry off an impure Air, which is noxious to An mal Life. 
 
 According to late experiments, it appears, that the Venous 
 Blood parting to the Lun;s, of a dark red or purple colour, is 
 charged with Carbon or Charcoal, and Hydrogen, or Inflamma- 
 ble Air; — that while crcularing upon the Bronchial Cells, one 
 part of the Oxygen, or V.tal Air, contained in the common Air 
 which has been infpired, Unites with the Carbon and. lydrogen, 
 ant forms Fixed Air and a Watery Hal.tus, whi.b are earned 
 off by Expiration ; — that another part of the Oxygen is imbibed 
 by the Blond, which, in confequence of thef'e changes, returns 
 from the Lungs, of a florid red colour, and full of heit in a 
 latent (late, which becomes fenlible in the coilffe of the general 
 Circulation, and is diffufed over the different parts of the Body ; 
 and,— hat the Blood thus changed alfo affords a St, nidus to the 
 Arteries, and promotes the different Secretions. 
 
 Esophagus. 
 
 • iHe Esophagus, called aifo- Gala or Gullet , derives its 
 name from can ying whet is eaten into the Stomach. 
 
 It is a tieftiy Canal, which begins fr, m t ie nferior part of 
 tne Pnarvnx, dec end along the Neck, and through the Thorax, 
 following nearly t ie direaion of the Spine 
 
 It is tituated between the Trachea and Vertebra ; and in the 
 Thorax, ,t proceeds behind the Bafe of the Heart, and between 
 
 ..e -ayeis of the Polterior Me.diaihnum, fioin which it receives 
 a lateral covering. 
 
 Soon after entering the Thorax, it makes a flight turn to the 
 r-ht, and partes down upon the fore and right fide , f the Aorta, 
 b) w h i n tney are- prevented fr, m injuring each other. 
 
 ;' S l >ro S re!s > inclines more forwards and to the left fide: 
 and aoom the Ninth Vertebra of the Thorax, it perfura es the 
 
 anJ teiini — - “PI- 
 
 Vol. II. H 2 
 
 
so 
 
 It has fevrral Coats proper to it, the ft, ft f which is Cellular, 
 and conn £ls it to the adjacent par s. 
 
 The ffcond Coat is Mufcular, and is fonsetimes termed Vagi- 
 nalis GuLe. — It con inis ot two Layei s ■, the external of which 
 has thick, lining, longitudinal F.bres ; the internal is forme I of 
 Circular and tranfverfe Fibres, and is thinner than the former. 
 — The outer Layer is fitted for fhorten ngand relaxing, and the 
 inner for contracting the Canal, during Deglutition. 
 
 The third Coat is termed Nervous, but is properly Cellular, 
 being formed of loofe Cellular Subltance, which councils the 
 Mufcular to the Inner Coat. 
 
 The Inner Coat is continued from the Lining of the Mouth : 
 It confilts cl many longitudinal Plica 1 or Folds, which are 
 fcarcely vifible when the Efophagus is dilated, and is funufhed 
 with numerou Foramina, which difeharge a Mucus for lubri- 
 cating the paflage, anil facilitating Deglutition. 
 
 The Arteries of the Efophagus are Branches of the Inferior 
 Laryngeal', which fupply the Cervical part of it, and Efopha- 
 geils and Branches of the Bronchials, which are derived fiom 
 the Aorta Defcendens, and fupply the Thoracic part of it. 
 
 The Veins go to >he inferior Laryngeals, to the Vena Azygos, 
 and left Superior Jut: recital Vein. 
 
 i he A'olbrbents are numerous, and intermix with thofe of the 
 Heart and Lungs. 
 
 The Nerves are chiefly from the Eighth Pair. 
 
 TTe ufe of tiie Efophagus is, to receive the Aliments from the 
 Pharynx, and convey them to the Stomach. 
 
 Thoracic Duct. 
 
 The Thoracic Duct is a i mall Membranous -like Canal, 
 fttuated in tile back part of the Thoiax, and is the principal 
 Tiunk of the Abforbent Syflem. 
 
 It begins upon the thud Vertebra of the Loins, and paffes be- 
 hind the Aoita, eroding obliquely from left to right, till it gets to 
 the r'glit fide of iha Artery. 
 
 Upon the fidl Lunibai Veitebir, 1 foims an Oval Sac, term- 
 ed Receptaculum Chyli , wh ch is , i ced behind the Right C> us 
 of toe Diaphragm, and a iiitle higher than the Right Renal 
 Artery. 
 
 The Du£l afterwards paffes between the Cruiaof the Dia- 
 phr gm, and allends in the Thorax, on the anterior part of the 
 Spii e, : etween the Layers of the Pofterior Mediallinuro, on the 
 right fide of the Aorta, and between it and the Vena Azygos. 
 
 It erodes behind the upper part of the descending Aorta, and 
 emerges fiom the Thorax, to reach the under part of the 
 Neck. 
 
 In the Neck, it paffes behind the Internal Jugular Vein, and a 
 little higher than the Subclavian. 
 
91 
 
 It then turns downwards, forming an Arch, which termi- 
 nates in the upper part of the Angle, between the Internal Jugu- 
 lar and Subclavian of the Left Side. 
 
 The Thoracic Duft receives the Chyle from the L:.£leals, and 
 Lymph from the Lymphatics, and difcharges thefe into the red 
 Veins. 
 
 »^»oooooooo @00000000 **■- 
 
 OF THE ABDOMEN. 
 
 The Abdomen or Belly extends from the Thorax to the under 
 part of the Trunk. 
 
 It is bounded above, by the Diaphragm, and the Bones to 
 which that Mufcle is fixed; below, by the Pelvis; behind, by 
 the Lumbai Vertebrae and Mufcles of the Loins; anteriorly, by 
 its Proper Mufcles ; and laterally, by the Falfe Ribs, Ofia Ilii, 
 and Mufcles connected with thefe; — all of which have been de- 
 fcribed in their places. 
 
 It is diftin 0 uiflied into three Di-vi/ions or Regions, termed Up- 
 per, Middle, and Under Region ; each of which is fubdivided 
 into three others. 
 
 The Upper Region begins oppofite to the Carfilapo Enfiformis, 
 at a fmall depreffion called Scrobiculus Cordis, or Pit of the Sto- 
 ma. h, and extends to about a hand-breadth from the Umb.licus 
 or Navel. 
 
 The mddle of this Region is termed Epigajirium, or under 
 part of the Belly, and the two lateral paits Hypochondria, from 
 their lying under the Cartilages of the Falfe Ribs. 
 
 The Middle Region occupies an equal distance above and be- 
 low the Umbilicus. — I'he middle part of it s called the Umbilical 
 and its lateral pirts the Lumbar Regions or Loins. 
 
 The Under Region begins where the middle one terminates, cr 
 at a line drawn between the fuperior anterior Spinous Procefl'es 
 of the Oifa Ilii, and forms in the middle, the HjpogaJlrium or 
 bott< m T the Belly ; and at the Tides, the Iliac Regions. 
 
 The Abdomen is covered on the outfide bv the common Integu- 
 ments, and l’ned within by the Peritoneum, in the manner the 
 Thorax is lined by the Pleura, but without being divided by the 
 intervention of a Partition. 
 
 The Abdomen contains the Cbylopoetic and Afjiftanl Chylopoeiic 
 Fife era or Organs of Digefion , — the Organs of Urine, and part of 
 
92 
 
 thofe of Generation, with the Vefj'els and Nerves which belong, 
 fome of them to thefe Vifcera, and others to the lower parts of 
 the Body. 
 
 The Cbylopoelic Vifcera comprehend the Stomach, which is fi- 
 tuated in the Upper and left part of the Abdomen, — the Intefines, 
 which fill the greater part of it, — and the Membranes, termed 
 Omenta and Mefentery, which are conne&ed with thefe. 
 
 The AJJiflant Cbylopoetic Vifcera conlift of the Liver, which is 
 placed in the upper and right; of the Spleen, which is fituated 
 in the upper and left fide of the Abdomen ; — and of the Pancre- 
 as, which lies undei the Stomach. 
 
 Of the Organs of Urine, the Kidneys are placed in the back- 
 part of the Abdomen, and the Bladder, with iome of the Organs 
 of Generation in the Pelvis. 
 
 Peritoneum. 
 
 The Peritoneum, named from its being ftretched or fpread a- 
 round the Bowels, is a firm but fimple Membrane, by which the 
 Abdominal Vifcera are furrotinded, and pai tly fupporled. 
 
 Its External Surface is rough and Cellular, and clofely con- 
 nected with the parts to which it belongs. 
 
 The Internal Surface is remarkably fm.ooth, and lubricated 
 by a Liquor which is exhaled from its own VefTels. 
 
 It is very elaftic, and admits of great extenfion, as happens 
 in Geilation, Corpulency, or Afcites; but, upon the caufes of 
 extenfion being removed, it returns to its former dimenfions. 
 
 It lines the Diaphragm, paffes downwards, adhering firmlvto 
 the Abdominal Muicles, — lines the containing, and covers the 
 contained parts of the Pelvis, from which it is rePitCIed in the 
 bar k-part of the Abdomen, lining its Mu cles, and, by its re- 
 duplications, covering the Bowels and great Blood- vefl'els of that 
 Cavity; — thorp h, (inCtlv ipeaking, the Abdominal Vifcera may 
 be fa i d to lie 0.1 the outfide of it. 
 
 In its pafta.e from one Bowel to another, it forms doublings 
 which f'erve as Ligaments to fix them to each other, and like- 
 wife to the Body. 
 
 It gives a general covering to mod of the Bowels, a partial 
 one to a few, and to thofe which are deep-feated, and projecl lead, 
 ■a (fill more partial covering. 
 
 It forms a large Sac, tlu pnfteripr part of which adheres firm- 
 ly t > the differt; t Vifcera, and the anterior to the Ah loin nal 
 MolCies ; — he par lining the Abdomen being merely in contact 
 with ns Co tents, and allowing a (mail degree of motion. 
 
 Til Cellular Sub.. ance, on the Ex'.ei nal Surface of tins Mem- 
 brane, in not every whe. e of equal thicknefs, being m fome parts, 
 as upon lilt Bowels, remuka ly thin; in ethers, as over the 
 . Kidneys, filled with a cunfiderable quantity of Fat. 
 
93 
 
 The Cellular Subftance forms various Precedes or productions, 
 feme of which, as thole on the Spermatic Cord's, pafs through 
 Foramina, to be connected with the neighbouring parts ; and the 
 Proceffes are fent off, without affeCting the Internal Membrane, 
 the one not. accompanying the other. 
 
 The Fejfels and Nerves of the Peritoneum are from thofe which 
 fuppjy the, contiguous parts ; its Veflels, however, are not very 
 mimetous; neither does it p off. is much S enlibi 1 i ty when free 
 from difeafe. 
 
 The Arteries come from the Internal Mammary, Epigaltric, 
 Inferior Inte, coftai, Lumbar, Sacral, and lleo lumbar Arteries, 
 and from thofe whica fupply the Abdominal VilCeva. 
 
 The Veins have the fame courle, bear the fame names, and in 
 general pals to the Inferior Cava. 
 
 The Abforbents are numerous, and run chiefly to the Iliac and 
 Lurubar Plexus. 
 
 . ..The Nerves, which are few in number and fmall, are from 
 the Inferior Dorfai, the Lumbar, the Great Sympathetic and 
 Sacral Nerves. 
 
 The ufe of the Peritoneum is to line and ftrengthen the Cavity 
 of the Abdomen ; to inclofe and aflift in fuppprting its different 
 Vifcera ; to furnilh molt of them with an External Coat ; to con- 
 ned them to the Body, and, by its fmoothnefs and fiipperinefs, 
 to prevent the effeds of FriCiion. 
 
 Upon the outfid,e of the Peritoneum are Four White Lines, or 
 fmall Cords, three of which are Veflels in the Fcetus,— one of 
 them a Vein, and two of them Arteries ; the fourth is the Ura- 
 chus. — In the Adult, they are fhrivelled up, and ferve as Liga- 
 ments, the Vein forming the round Ligament of the Liver, the 
 three other Cords, foiming Ligaments of the Bladder. 
 
 STOMACH. 
 
 Til E Stomach is a large Bag or Refervoir, fituated obliquely 
 acrofs the upper and left part of the Abdomen, in the left Hy- 
 pochondriac and Epigaftric Regions. 
 
 It is turned downwards and fo. wards, fo as to form an angle 
 wtth the Efophagus, the angle becoming more confpicuous, ac- 
 cording to the diiftenfron of the Stomach. 
 
 I he right part of the Stomach is fituated under the left part of 
 the Liver, the reft of it is placed immediately under the Dia- 
 phragm, its extremity being in coiitaft with the Spleen. 
 
 The Stomach is long, round, and tapering, acd has beeo 
 compared in fliape to the Bag of a Bagpipe. 
 
94 
 
 The Cize is in proportion to the quantity of Aliment it has 
 been accuftomed to receive, and therefore is commonly larger in 
 Men than in Women. 
 
 it has a Labge and Small Extremity , ah Upper and Under Sur- 
 face, a Great and Small Curvature, a kept and Right Orifice , 
 and confifts of feveral Layers or Coats. 
 
 The Large, called alfo the Left Extremity, is fituated in the 
 left fide of the Abdomen, and is confiderably higher than the 
 Tight. 
 
 The Upper Surface is turned towards t he Diaphragm, the Un- 
 der towards the Inteftines; but when the Abdomen s Hid o- 
 
 pen,— unlefs the Stomach be conliderabiv d i (tended , — the Supe- 
 rior Surface becomes anterior, and the Inferior Surface poitcrior. 
 
 The Large Curvature is turned obliquely forwards and down- 
 wards towards the Abdominal Mufcies, and extends from one 
 Orifice to the other. 
 
 The Small Curvature is oppofed to the other, and turned 
 backwards and upwards, towards the Spine, extending alfo be- 
 tween the two Orifices. 
 
 The Orifices are next the Small Curvature. The left is termed 
 Cardia, or Os Ventriculi, or Upper Orifice of the Stomach. — It 
 is oppofed to the Spine, at a little diftance from it, and is for- 
 med by the termination of the Efophagus.' — It allow* a free Paf- 
 fage for the Food into the Stomach, the return ol which is pre- 
 vented by the Angle formed by this part of the Stomach, and 
 by the Flefhy Parts of the Cardia, and of the Diaphragm in 
 which it is fituated. 
 
 The Right, or Inferior Orifice, is commonly termed Pylorus 
 from its office as a Porter. 
 
 It is fituated under the fmall Lobe of the Liver, a little to 
 the right fide of the Spine, — is turned more forwards than the 
 Cardia, and is confiderably lower, but rifcs in proportion to the 
 diftenfion of the Stomach. 
 
 The Stomr.ch is conneXed by the Cardia to the Efophagus,-— 
 by the Pylorus to the beginning of the Inteftines, — by the Peri- 
 toneum and Blood-vefi'els to the Spleen, — and by a refleXion of 
 the Peritoneum to the root of the Liver and to the great Intef- 
 tines. 
 
 The Strufiure of the Stomach is in general fimilar to that of 
 the Efophagus, of which it is a kind of Expanfibn. 
 
 The Coats uf the Stomach are four in number. 
 
 The firft or External Coat, called alfo Peritoneal, is a Reflexi- 
 on of that part of the Peritoneum which comes from the root of 
 the Liver. 
 
 It ftrengthens the Stomach ; by its fmoothnefs it diminifhes 
 the efteX of FriXion, and poffeffing few Nerves or Blootl-vefiels, 
 it is not very fufceptible of pain or inflammation. 
 
95 
 
 The Cellular Subftar.ee under the Peritoneal Covering, is def- 
 cribed by fonie Authors as a diltincl Co -it, called Tunica Cellu- 
 lofa Ruyfchiana ; — but ought not to be numbered among the 
 Coats of the Stomach. 
 
 The Second or Mufcular Coat is ccmpofed chiefly of two 
 Planes of Fibres variously dilpofed. 
 
 The External Plane is Ion . itudinal, extends from the longi- 
 tudinal Fibres of the Efophagus, and follows the f. me general 
 courfe with that of the Stomach from the Great to the Small Ex- 
 tremity. 
 
 Upon each fide of the Small Curvature, the longitudinal Fi- 
 bres form a thick, ftrong, Mufcular Band. 
 
 The fecond Plane is chiefly tranfverl'e or circular, and confi- 
 derably thicker and ftronger than the other. 
 
 Its Fibres are interfered by many lmall, whj*e, Tendinous- 
 like Lines ; — thefe, however, are in a great meafure formed of 
 that Cellular Subftance by which the rwo Coats are united. 
 
 The Mufcular Coat affifts in the Digeftion of the Food, by 
 giving a gentle motion to the Stomach, accordin ; to the direflion 
 of its Fibres, the one fet fhortening, the other rendering it nar- 
 rower. 
 
 The Pylorus is formed by a doubling of the two inner Coats, 
 which project into the Pafface between the Stomach and Intef- 
 tine, and contain a Ring of Mufcular Fibres, which form a 
 Sphincter, called Sphincter Pylori. 
 
 This lublt2nce, by contrailing, prevents the gre (Ter ind gefted 
 parts of the Aliment from efcaping, and, by dilating, allows 
 the Pulpy digefted part to pals to the Inteftines. 
 
 The Third. Coat , commonly called Nervous, but properly Cel- 
 lular, confifts of a large quanfty of fine Cellular Subftance, 
 without Far, and is intermixed with, and fupported by fmall 
 Aponeurotic like Filaments, which crofs each other obliquely, 
 but which are alfo of a Cellular nature. 
 
 This Coat ftrengthens the Stomach, and allows the Veflels to 
 be diftributed to the Inner Coat, with which it is intimately con- 
 nefled. 
 
 The Fourth or Inner Coat, called alfo Villous, from its refem- 
 blance to Velvet, is continued from the Inner Coat of the Eio- 
 phagus, but is much more Villous. — It is formed of fine, fhort, 
 prominent Villi, which are crowded with Small Veflels, fome for 
 furnifhing a Mucous Liquor to the Stomach, others for abloibing 
 a portion of the thinner part of the Food. 
 
 The two laft Coats are more extenfive than the reft, and form, 
 upon the inner part of the Stomach, many doublings, termed 
 Ruga, the greater number of which run in a waving tranlverfe 
 direflion, and are afterwards divided Into a fort of Net-vuork , 
 
96 
 
 Near the Orifices, however efpecially towards the upper one, they 
 run more in a longitudinal direflion, and have a radiated appear- 
 ance at the Cardia. 
 
 The Rugae, like the Plicae of the Efophagus, are molt diftimft 
 when the Stomach is empty ; — when full, they are much lefs 
 evident. 
 
 They admit of diftention without endangering the VefTelS and 
 Nerves difperfed in them, and aflift a little in detaining the Ali- 
 ment till properly digefted. 
 
 From the Inner Surface of the Stomach a Liquor iffues, which 
 is found to approach' to the nature of Saliva, and is termed Gaf-. 
 trie Juice . — This was formerly fuppofed to come from Glands 
 feated in the Third Coat, but is now more frequently cOnfideVed 
 as a Secretion from the Aiteries of the Stomach, no Glands be- 
 ing evident there, at lead in the found (late of this Vifcus. 
 
 The Arteries of the Stomach aie derived from the Coeliac 
 Artery. They confift of the Superior Gaftric, which fupplies the 
 place next the final! Curvature • the Right Infer ior Gaftric, which 
 is a bianch of the Hepatic; the Pyloric Arteres, which are 
 final! branches from the Gaftrics and from the Hepatic ; and of 
 the Left Gaftric and Arteriae breves, which are branches of the 
 Splenic Artery. 
 
 The Veins have the fame names, and nearly the fame courfe 
 with the Ai teries. 'J he whole of them terminate in the Vena 
 Port®. 
 
 The Abforbents of the Stomach are numerous and large. They 
 pafs through final! Glands fituated upon the Curvatures, and go 
 afterwards to the Thoracic Du£t. 
 
 They appear to carry Lymph only, no Chyle having been dr 
 tested in them, evur in cates where the Lafteals were found full 
 of it. 
 
 The Nerves are chiefly from the Eighth Pair, and partly from 
 the Gi eat Sympathetics, and are moft numerous upon the Car- 
 dia. 
 
 The Stomach receives the Food from the Efophagus, and af- 
 terwards prepares it, by digeftion, fur the Inteftir.ss. 
 
 The digtftion of the Food in the Stomach is found to be efrer. 
 ted, — by Trifure, which is performed by the motions of the 
 Stomach and furr minding Mtifcles, — by dilution, — by a partial' 
 fermentation. — but chiefly by the action of the Gaftric Juice Li- 
 ving as a Menltruum. 
 
97 
 
 INTESTINES. 
 
 The InteJHnes eonfift of a long Cylindrical Canal, which be- 
 gins at the Inferior Orifice of the Stomach, and, after winding 
 in various directions, terminates in the Anus. 
 
 In general they are about fix timesthe length of the Body to 
 which they belong ; though, in a perlon of fhort Ifature, the pio- 
 portional length of the Inteftines is greater, and vice ve<fa. 
 
 They occupy a large part of the Abdomen, and are connected 
 to the Body through their whole extent, by a doubling of the 
 Peritoneum. . 
 
 On account of the inequalities of their fize, they are divided in- 
 to Small and Large Intelfines, and each of thefe is fubdivided in- 
 to others. 
 
 Small Intestines. 
 
 The Small Intejlines are fmooth on their outer Surface, and of 
 a tapering form, becoming gradually Ids in their diameter from 
 their upper to their under extremity, and are divided into the 
 Duodenum , Jejunum, and Ilium. 
 
 The Duodenum, fo called from its being about twelve fingers- 
 bneadth in length, begins at the Pylorus, and makes a fhort 
 turn upwards and backwards, by the Neck of the Gall-bladder, 
 to which it is contiguous, having the Anterior Layer of the 
 Omentum fixed to its inferior part, and the Omentum Minus to 
 its oppofite fide. 
 
 It then palTes obliquely downwards and to the right fide, before 
 the great VefTels which go into the Liver, and likewiib before the 
 .Renal Artery and Vein, included in the Ceilular Subftauce of 
 the Mefocoion. 
 
 Oppofite to the under part of the Kidney, it makes a turn to 
 the left fide, where it is lodged in the common root of the Me- 
 focoion and Melentery, and receives into its back-part the ends 
 of the Biliary and Pancreatic Duds, and goes over the Aorta and 
 Vena Cava, oppofite the laft Vertebra of tiie Back. 
 
 In palling acrofs thefe VefTels, it is involved in the root of the 
 Mefentery, and afeends a little t : 1 1 it gets to the left fide of the 
 Spine, where it perforates the common root of the Mefentery and 
 Mefocoion, and makes a turn forwards, where it obtains the 
 narpe of Jejunum. 
 
 The Jejunum fo named from its being commonly more empty 
 than the other Inteftines, in confequence of the thinner parts of 
 its Contents being fooner abforbed, begins at the laft turn of 
 ♦he Duodenum, aud forms numerous Convolutions, which run in 
 all directions, and are fituated in the upper part of the Umbili- 
 cal Region. 
 
 VOL. II. 
 
 I 
 
98 
 
 The Ilium , named from its numerous Turns, begins where 
 the Jejunum terminates, or where the Internal Plicae become lefs 
 confpicuous, and is diftinguifhed externally from that Gut, by 
 being fmaller, thinner in its Coats, and paler, and from its 
 forming about three-fifths of the length of the two Inteftines. 
 
 The Ilium, like the Jejunum, forms many Convolutions, 
 which are fituated on the under part of the Umbilical Region, and 
 extend as far as the Hypogaftric and Iliac Regions, and not un- 
 frequently, efpecially in Women, into the Cavity of the Pelvis. 
 
 It furrounds the lateral parts of the Jejunum, and is fupport- 
 
 by the Offa Ilia; and, the laft turn of the Gut parting acrofs 
 towards the upper edge of the Right Os Ilium, it terminates by 
 a Valve in the left fide of the beginning of the Colon. 
 
 Through the whole of this couife, the Jejunum and Ilium 
 are fixed to the Spine by a continuation of the Mefentery. 
 
 Great Intestines. 
 
 The Great Intejlines, like the Small, form one continued Ca- 
 nal, which tapers from its upper to near its under extremity ; 
 but differ from them in being confiderably larger, fhorter, and 
 flraighter, and in being irregular in their Outer Surface, and 
 tacked up into Cells, having beficles many Precedes depending 
 from them, termed Appendiculce Pinguidenofa? . 
 
 Like the Small Inteftines, alfo, they aie divided into three 
 parts, termed Cacum, Colon, apd Re Sum. 
 
 The InteJUnum Cacurn, or Blind Gut, forms a round fhort Bag, 
 only about three or four Fingers-breadth in length, and nearly 
 the fame in diameter. The Caecum, properly fo called, is that 
 part of the Inteliine which lies under the Iniertion of the Ilium, 
 through frequently the dilated beginning of the Colon is diftin- 
 gui filed by the fame name. 
 
 It is fituated in the Right Iliac Region, retting on the Cavity 
 of the corrcfponding Os Ilium, at the under end of the Right 
 ‘Kidney, and is concealed by the laft Convolutions of the Ilium. 
 
 The bottom of it is turned downwards, and forms a fhut 
 Sac, the mouth of which is turned towards the Colon, and may 
 be confidered as forming the Ceecum Caput Coli. 
 
 At the poftei ior and left fide of the Caecum, there is a fmall 
 Proeefs, about the fame length with the Caecum itfelf, but the 
 diameter not larger than that of a Goofe-quill,— termed Appen- 
 dix' Vermiformis, from its refemblance to an Earth-worm, and 
 Appendix Ca-ei, from its connection with the Caecum. 
 
 It is convoluted, and fixed by its fides to the Caecum. 
 
 It has two extremities, one of which is impervious, the other 
 ®pens obliquely into the back-part of the Caecum. 
 
 The Colon, fo called from the Greek, is by much the longeft 
 of the Lar«e Inteftines. It encircles the Small Guts, and is con- 
 tiguous to mod of the Abdominal Vifcera, 
 
It is a continuation of the Caecum, beginning at the termina- 
 tion of the Ilium. 
 
 It attends in the Right Lumbar Region, over the Kidney of 
 that fide to which it is conne6ted. 
 
 From the Kid ;ey, it puffes forwards, and erodes the Abdo- 
 men in the Epigalcric and Hypochondriac Regions, connected to 
 the Duodenum, under the name of Great Arch of the Colon, 
 
 Theri ,ht portion of the Great Arch is tnuated under the Li- 
 ver and Gall-bladder, which, after death, commonly tinges part 
 of it and of the Duodenum with Bile. 
 
 The left portion is lituated under the Stomach; and immedi- 
 ately below the A.ch are the Convolutions of the Jejunum. 
 
 In the Left Hvpochondriuro, it turns backwards under the 
 Spleen, and defends in the left Lumbar Region, on the fore- 
 fide of the Kidney, to which alfo it is clofely connected. 
 
 In the Left II ac Region, it forms two Convolutions, com- 
 pared in fhape to the Greek Sigma , and hence called Sigmoid 
 Flexure of the Colon, wh ch afterwards conllitutes the Reftum. 
 
 The Sigmoid Flexure varies confiderably in length in different 
 perfons, extendng fiequently into the Hypogallric Region, and 
 in feme inftances, as f r as the Inteltinum Caecum. 
 
 The Colon, through its whole extent is fixed to the Body by 
 means of the Mefocolon. 
 
 The Reflum begins at tjte laft Lumbar Vertebra, and has its 
 name from appearing ftraight when viewed anteriorly. 
 
 Itdcfeends upon the fore-fide of the Os Sacrum and Os Coc- 
 cygis, and terminates ir. the Anus, a little beyond the extremity 
 of the lalt named Bone. 
 
 In its courfe, it follows the direction of the Bones over which 
 it paffes, turning firft downwards, then a Hide backwards, then 
 forwards, and is fixed to them by the Mefore&um. 
 
 The Reftum differs from the other Inteftines, in becoming 
 wider in its prog refs downwaids, and forming below a Refer- 
 voir for the Faxes. 
 
 At the Anus, it contrails into a narrow Orifice, the fides of 
 which are d'l'pofed in clofe longitudinal folds. 
 
 Upon the Outer Surface of the Great Inteftines, but more 
 efpecially upon the Colon, are the Appendicitis P inguedinojee , fi- 
 tuated at different diftanecs from each other, — thin at their roots, 
 becoming thicker in their bodies, and projeiling from the Intef- 
 tines like fo many pendulous Papillae. 
 
 They are covered by the Peritoneum, and are of the fame 
 ftruflure and ufe with the Omentum. 
 
 Befides the Appendiculae, there are on both fides of the adhe- 
 fions of the Mefocolon, Adipofe Strata , which are of the fame 
 nature with the others. 
 
 The Colon is divided, longitudinally, into three parts, by as 
 many Livamentous-hke Bands , which run upon its Su • f 
 
100 
 
 One of them goes along each fide of the Colon ; and that molt 
 expofed to view when the Omentum is leparated, is the largeft : 
 The tliiid, which is the fmalleft, and which was difcovered by 
 Morgagni, is concealed by the attachment of the Melb-colon. 
 
 They begin at the root of the Appendix Vermiformis, and, 
 after running along the Caecum and Colon, unite into two, and 
 then terminate on the Return. 
 
 Mesentery. 
 
 The Mefentery is formed by a doubling of the Peritoneum, 
 which is detached forwards, and includes the Inteftines as in a 
 Sling. 
 
 It is named from its fituation in the middle of the Inteftines, 
 and is divided into two parts, one connecting the Small Intef- 
 tines, and retaining the name of Mefentery ; the other, the Great 
 Inteftines, and termed Mefocolon. 
 
 The Mefentery begins at the laft turn of the Duodenum, and 
 runs obliquely downwards and towards the right fide,- along the 
 Vertebrae of the Loins, to the firft, fecond, and thiid of which 
 it is chiefly connected. 
 
 Between the two Layers of the Mefentery, are inclofed a con- 
 fiderable quantity of Cellular Subftance and Fat, the numerous 
 Blood-veffels and Nerves, with the LaCteals and Glands of the 
 Jejunum and Ilium. 
 
 Its anterior edge is much more extenfive than the pofterior, be- 
 ing plaited and folded, — the Plaits correfponding with the Con- 
 volutions of the Inteftines to which it is fixed. 
 
 The Mefo-colon is the continuation of the Mefentery, which, 
 after reaching the lower extremity of the Ilium, contracts, and 
 obtains this name. 
 
 It follows the courfe of the Great Inteftines, and fixes them 
 in their place. 
 
 Under the Right Kidney, it is narrow and firm, and forms 
 the Right Ligament of the Colon. 
 
 Oppofite to that Kidney, it appears to be loft by the immedi- 
 ate adhefion of the Colon to the Kidney and Duodenum. 
 
 It then tui ns acrofs, and forms a broad expanfion, which in- 
 clofes the Arch of the Colon at its anterior edge; and behind, 
 it ieparates and inclofes the anteiior part of the Duodenum, and 
 is fixed to the Spine. 
 
 It adheres a little to the under part of the left extremity of 
 the Stom3ch, and aftei wards defeends over the left Kidney, at 
 the under end of which it forms the left Ligament of the Colon. 
 
 It afterwards expands, adheres to the large Pl'oas Mufcie, and 
 forms a loofe fold, which retains the Sigmoid Flexure of the 
 Colon. 
 
 At the laft Vertebra of the Loins, it forms the Mefore&um, 
 which by decrees becomes narrower, and difappears towards the 
 
101 
 
 under part of the Pelvis, the Reftum being then immediately 
 connected to the Os Sacrum. 
 
 Between the Layers of the Mefocolon are placed the Arteries, 
 Veins, and Nerves, will* the Abforbents and Glands of the Co- 
 lon. . _ 
 
 The ufe of the Mefentery, in general, is to fufpetid, connect, • 
 and retain the Inteftines in their places,— to furnilh them with 
 an external Coat, — to receive the^r Glands, Veflels, and Nerves, 
 and to allow the two lalt to be properly diftributed. 
 
 Omentum. 
 
 The Omentum or Canjul, formerly called Epiploon, from its 
 feeming to float upon the Inteftines, is a fine Membranous Bag, 
 intermixed with much Fat, and covering a large portion of the 
 Anterior Surface of the Abdominal Vifcera. 
 
 It is divided into Omentum Gafro-colicum, and Omentum Coli- 
 cum, the former common to the Stomach and Colon, the latter 
 proper to the Colon : They are, however, a continuation of one_ 
 and the fame lubftance. 
 
 The Omentum Gafro-colicum confifts of an anterior and pofte*. 
 rior part, each of which is formed of two Membranes intimate- 
 ly unired. 
 
 In young fubjefts, the Omentum forms a diftinft Bag, but in 
 old people, the layers of which it is compol'ed become more or 
 lefs incorporated, and Cribriform or Reticular. 
 
 The Anterior Layer is a continuation of the Peritoneal Coats, 
 produced from the upper and under Surfaces ef the Stomach. 
 
 This Produ£lion arifes from the whole length of the large 
 Arch of the Stomach, and beginning of the Duodenum ; — its 
 origin extending as far as the Spleen, and del’cending to a little 
 below rhe Umbilicus, efpecially in fat people,— but without ad- 
 hering to the Abdominal Mul'cles behind which it is fituated. 
 
 Its under edge is refiefled, to form the Pofterior Layer, which 
 alcends without adhering ro the Small Inteftines over which it is 
 fpread, till it reaches the Arch of the Colon, to the greater part 
 of which Arch, and to the Veflels of the Spleen, it is connected. 
 
 The Omentum Colicum arifes from the right part of the Arch 
 of the Colon, in the manner the other part of the Omentum a- 
 riles from the Stomach, and fends downwards and to the right 
 fide a Cuneiform Procefs, 10 be con.ne&ed to the Caecum. 
 
 Befides the Omentum, there is a Membrane much fmallerthan 
 the former, fituated between the Liver and Stom tch, termed 
 Omentum Hepato-gafricum, or Omentum minus of Winslow, 
 or Membrana Macitentior of Haller from its having little Fat 
 in it. 
 
 It paffts from the foie-part of the Sinus of the Porta, to the 
 under and back-part of the Liver, to be conne&ed to the whole 
 
 VOL. II, I 2 
 
102 
 
 edge of the (mall Curvature of the Stomach, and to the begin- 
 ning of the Duodenum. 
 
 L ke the other Omentum, it is compofed of two Layers, but is 
 thinner, lets F.-.t, and more uniform in its ftruflure, and alfo 
 differs from it in having no refleflion upwards. 
 
 After the Omentum M nus reaches the Stomach, its two 
 Layers feparate from each other, inclofe that Vilcus, and form 
 it; External Co t. 
 
 A. the great Curvature of the Stomach, they rejoin, and form 
 the Anterior, then the refle&ed or pofterior part of the Omentum 
 Mnjus. 
 
 The pofterior part 'Separates again into two Layers, which 
 inclofe the Colon, and form its External Coat. 
 
 At the oppofite fide of the Colon, the Layers re-unite, and 
 form the Mefo colon. 
 
 By the Membrane thus continued, a large irregular Bag is 
 foimed, of which the Omentum Minus, Stomach, and anteriot 
 pori ion of the Omentum Majus, conftitute the anterior, and the 
 reflexion of the Large Omentum, the Colon, and Mefo-cclon, 
 the pofterior part. 
 
 At the upper and right fide of the Sac, there is a PafTage large 
 enough to admit a Finger, termed Foramen Winslowi. 
 
 It is fituated immediately behind the Coid of the great Veflels 
 which lead to the Liver, and is of a Semicircular form. 
 
 It is compofed of the Peritoneum, under the appearance of two 
 Ligaments which connect the funounding parts to each other. 
 
 The Foramen of Winslow maintains a communication be- 
 tween the Large Sac of the Omentum and common Cavity of the 
 Abdomen, from which circuniftance, Fluids generated by dif- 
 cnfe may readily pafs from one of thtfie Cavities to the other. 
 
 The Omentum, by its Fatty nature, ferves to lubricate the Vif- 
 ccra, and prevent them from being injured by friction. 
 
 Structure of the Small Intestines in General. 
 
 The Structure of the Small Inteft nes is nearly fimilar to that 
 of the Stomach, and the number of their Coats the fame. 
 
 The External Coat, excepting in a port ; on of the Duodenum, 
 is a continuation of that part ot the Peritoneum which forms the 
 Mefentery. It clofely furrounds the lnteftines, adhering to them 
 by fine Cellular Subttance. 
 
 The Second, or Mufcular Coat, as in the Stomach, is compo- 
 fed of two Planes ot Fibres, the External or Longitudinal of 
 which are more minute than the Internal. 
 
 The Circular Fibres are diftinft and numerous: They confift 
 of Segments of Circles, which unite at different diftances, fo as 
 to fui round ths Canal. 
 
 The Longitudinal Fibres ffiorten, and the Circular contract the 
 lnteftines; and upon the alternate relaxation and contrafticn of 
 
103 
 
 thefe Fibres, depends that Vermicular motion, called Perijialtic, 
 by which the Contents are pufhed through the Canal. 
 
 The Third commonly called Nervous Coat, like that in the 
 Stomich, is while and firm and compoled of Cellular Subftance, 
 without Fat ; — its firmnel’s giving; iirerigth to the Inteftines. 
 
 The Fourth, or Villous Coat, differs from that of the Stomach, 
 in forming, with the Cellular Coat, numerous tranfverfe Folds, 
 termed Vatvules Conniventes , from their ferving, as a kind of 
 Valves, to retard the motion of the Food. 
 
 One edge of thefe Valves is fixed to the Inteftine, the other is 
 loole.—- 1 hey are much deeper than the Rugae of the Stomach, 
 and placed oppofite to the Inierftices of each other, and are of 
 different lengths, not forming entire Circles. 
 
 The Villi of the Inner Coat are much more confpicuous than 
 in the Stomach, being compofed not only of the extremities of 
 Arteries, Veins, and Nerves, but particularly of the Mouths of 
 Laffeal Veffels, the Origins of which are extremely fmall, and 
 have a fungous appearance. 
 
 Numerous Dufts of Simple and Compound Glands terminate on 
 this Coat, for the fecretion of Mucus. 
 
 The former are called Solitary, and the latter Congregate 
 and, form their defcribers, Glandules Peyeri, and Glandules 
 Brunneri. 
 
 They are in the form of Papillae, but fo minute as feldom 
 to be leen, excepting in the difeafed Hate, — though they are fup- 
 pofed to be difperfed over the whole of the Canal. 
 
 Structure of the Small Intestines in Particular. 
 
 The Duodenum is the laxeft and ftraighteft of the Small Intef- 
 tines, and fo large as to have been conlidered as a Ventriculus 
 Succenturiatus, or Secondary Stomach. 
 
 It is of a redder colour than the reft, has a thicker Mufcular 
 Coat, receives only a partial covering from the Peritoneum, and 
 is fixed more clofely to the Body, without floating like the other 
 Inteftines. 
 
 It is perforated at the diftance of three or four fingers-breadth 
 from the Pylorus, bv the ends of ihe B. diary and Pancreatic 
 Duffs, for the reception of Bile and Pancreatic Juice. 
 
 In the Duodenum, the Laffeal Veffels begin to make their ap- 
 pearance, and numerous Mucous Glands are found in it efpeci- 
 ally near the Pylorus 
 
 The ufe of the Duodenum is to receive the Food from the Sto- 
 mach, and detain it till mixed with the Bile and Pancreatic 
 Duff. 
 
 The Jejunurn differs from the Duodenum in deriving its com- 
 mon Coat wholly from the Peritoneum, in being Invidtr, — in 
 having a weaker Muf’euia C v at, the external Fibres of which 
 are extremely minu.e,— in the Valval* Cormiventes being larger 
 
104 
 
 and more numerous,— -and in the Villi and Lafleals which pro- 
 ceed from them being much more confpicuous. 
 
 The Ilium differs from the former in being lefs in diameter, 
 and its Coats thinnei and of a paler colour, and in having fewer 
 and fmaller La&eal Veffels.— In this Inteftine theValvulae Con- 
 niventes gradually decreafe infize and number, and at length en- 
 tirely difappea. At its under end, the Mucous Glands are 
 diftin£t and numerous. 
 
 The ufe of the Small Inteftines in general is, — to promote the 
 formation of the Chyle, — to allow it to be abforbed, and — to 
 propel the remains of the food into the Large Inteftines. 
 
 Structure of the Great Intestines in General. 
 
 The Great have the fame number of Coats with the Small In- 
 teftines, but differ from them in being thicker and (Longer. — The 
 Valvulae Conniventes are deep, and placed oppofite to each other, 
 and, as in the Small Inteftines, dimimlh n number and in fize 
 towards the under extiem ty. — The Villous appearance is much 
 lefs diftin£L — r The Mucous Glands are larger, but fimpler than 
 thole of the Small Inteftines, 
 
 Structure of the Great Intestines in 
 Particular. 
 
 The Ir.tejlinam Caecum is of the fame general ftt'ufture with the 
 reft of the Great Inteftines. Its Villi are very (hort ; and it has 
 a number of i'olitary Mucous Glands, broader than thole oi the 
 Small Inteftines, which, when difeafed, lometimes appear like 
 fniall-paxy with a perforation in ea.li. 
 
 The Appendix Vermijormu is of the fame ftruflure wi h the 
 other Inteftines, contains no f aeces, but is furnilhed with nume- 
 rous Glands fimiiar to thofe of the Duodenum, the conents of 
 which pafs into the Caecum, a 1 tile feiow the Valve of the Co- 
 lon, and aftift in lubricating that Inteftine, and in facilitating 
 the expulfion of the Faeculent M iter. 
 
 In the Caecum, and beginnm of the Colon, the Food coming 
 from the Ilium is letained for fame time, and, in cor.lcquence of 
 abforjv ion, acquires a grea er degree of conliftency, end lece.ves a 
 foe id fmell. •' 
 
 The Culvula Coli , fomtlimes called V l-uula llei, or Valvula 
 Baughini, from its fuppofccl dife verei , ami Faivula-Tvi.PlX 
 from the Author who gives a particular dvfc i iptiou of it, is iitu- 
 ated at the beginning of ihe Colon, and is placed traniveriely in 
 the polterior and left part of that Inieftine. 
 
 It is formed of a pmjeflion of the Villous and Nervous Coats, 
 and Circular Muicui n Fibres of the Ilium, Caecum, ar.d Colon, 
 and has two Fouls or Lip , with an aperture in feum of a Mouth 
 or Chink be 1 ween them. 
 
 At the ends of the Valves aie two cords, termed Retinacula , or 
 
105 
 
 Freena Morgagnii, which retain the Valve in its proper fitu- 
 ation. 
 
 The Valve of the Colon allows a free paffage for the Contents 
 of the Small into the Large Inteftines, but completely prevents 
 their return. 
 
 The Colon is of a funilar ftrufhire with the Caecum.— T'ne 
 Longitudinal Mufcular Fibres are collated upon it into three 
 Fafciculi or Bands, which arife at the root of the Vermiform 
 Procefs, and are continued along the Colon to the Reflum. 
 
 The Longitudinal Bands are (hotter than the inner parts of the 
 Colon, and of confequence afiift in contracting it, and forming 
 it into Plicae, which lie acrofs the Gut, aufwenng to the Valvulx 
 Conniventes ; only they are at a greater diftance from each other, 
 and much larger, dividing the Colon into little apartments, called 
 Cells. 
 
 The Cells of the Colon , with their Partitions, have a threefold 
 order, the Inteftine being aimoft quite fmooth or plain, oppofite 
 to the Longitudinal Bands. 
 
 The Cells aflilt in preventing the too quick defcent of the Fae- 
 ces. 
 
 The ufe of the Colon is,— to receive the Excrementitious parts 
 of the Aliment,— to retain them,— to change them into Faeces, 
 and then, by the periftaltic motion of the Inteftines and power 
 ef Refpiration, to pulh them, by (low degrees, to the Re£h>m. 
 
 The ReSum differs from the Colon in being covered only an- 
 teriorly and laterally by the Peiitoneum Its Mufcular Fibres 
 are ftronger and thicker, and f read uniformly over the Inteftine. 
 —The Circular Fibres are fo thick at the end of the Reclum, as 
 to have been named Internal Sphincter. 
 
 It has no Cells like the Colon ; but the Cellular and Inner 
 Coat are fo much larger here than they are higher up, as to fall 
 into tranfvetfe folds, which, however, difappear in proportion to 
 the diftention of the Inteftine. 
 
 The middle and under end of the Reftum has numerous large 
 Mucous Glands or, Follicles. 
 
 The extremity of the Redum forms a firm Circle, which afts 
 as a Vaive, and afiifts the proper Sphinfter in preventing the in- 
 voluntary difcharge of the Faeces. 
 
 The Verge of the Anus is lurrour.ded with deep Follicles, the 
 contents of which pi event the tendei Skin of the Anus from be- 
 ing excoriated by hard or act'd Fx es. 
 
 The Anus is alfo lurrounded with a _ reat tfeal of Fat, which 
 admits of the dilatation of the Reffurn, and facilitates the dif- 
 char e of the Faeces. 
 
 The Reftum receives the Faeces from the Colon, retains them 
 for a cei tain time, till, by their weight and Acrid nature; it is 
 flimulated to difcharge them ; which it does by the power of its 
 
106 
 
 Mufcular Coat, and of the Levator Ani, affifted by the aftion of 
 the Diaphragmatic and Abdominal-Mufcles. 
 
 The Blood-veJJ'els of the Inteftines are large and numerous, and 
 are derived from d flferenr fources. 
 
 The Duodenum receives Branches from the Splenic and Hepa- 
 tic Arteries. 
 
 The Jejunum, Ilium, and right half of the Colon, are fup- 
 plied by the Superior Mefenti ic Artery ; and the lefi half of the 
 Colon with the Re£fum, by the Inferior Mtfemric Artery. 
 
 The Veins of all the Inteftines fend their Blood to the Vena 
 Portae. 
 
 The Abforbents of the Inteftines are large and numerous. — 
 They arile from the inner Surface of the Inteftines, tun in the 
 Mefentery and Mefo-colon, parting through their numerous 
 Glands.— The Abforbents of the Small Inteftines terminate in 
 the receptacle of the Chyle ; thole of the Large Inteftines, which 
 are fmaller than the former, gopaitly to theThoiacic Du£l, and 
 partly to the Lymphatics of the Loins. 
 
 The Nerves of the Inteftines are fmall, but numerous, and 
 are derived partly from the Eighth Pair, but chiefly fjom the 
 Great Sympathetic®. 
 
 The Veflels and Nerves of the Omenta are Branches of thofe 
 •whi,ch fupply the Stomach, and have the name of Gajiro - 
 Epiploic. 
 
 LIVER. 
 
 The Liver is a large folid Mafs, of a dufky red colour, fitu- 
 ated immediately under the Diaphragm, extending downwai ds 
 to the margin of- the Thorax, but not going beyond t. 
 
 It is placed partly in the Right Hypochondrium, which it in a 
 great meafute fills, and partly in the Epigalhium, reaching over 
 a little way into the Left Hypochondrium. 
 
 It is convex and very fmooth on the upper Surface, where it is 
 oppofed to the Diaphragm, though a l.ttle flattened on the up- 
 per part of its left fide, svhere it is placed oppofite to the Heart. 
 
 It is irregularly concave on the under fid'-, where it refts upon 
 the Stomach and Inteftines, and is perforated by feveral large 
 Blood-vefFels. 
 
 It is thick on its right and pofterior part, and becomes gradu- 
 ally thinner towards the left fide ; is ohtufe or blunt on its pofterior, 
 and acute or Jbarp on its anterior edge, — and confiderably broad- 
 er ftotn one fide to the other, than from before backwards. 
 
107 
 
 It is divided into Prominences or Lobes , two of which, called 
 Great and Small, or Right and Left Lobes, are fo confiderable as 
 to form the Body and whole upper part of ibe Liver— The 
 others are 1’malJ, and are placed upon the under fide of the for- 
 mer. 
 
 The Great Lobe is placed obliquely in the Right Hypochondriac 
 Region, following the Curve of the Diaphragm, and relts upon 
 the Pylorus, Colon, and top of the Right Kidney. 
 
 The Small Lobe, diftingu fhed from the Great one by a broad 
 Ligament, is placed almolt horizontally, chiefly in the Hepeaftic, 
 and reaching only a little way into the Hypochondriac Region. 
 
 —The other Lobes are, — 
 
 The Lobules Spigelii, which is fmall when compared with the 
 two former Lobes, but is the principal one below. 
 
 It is fituated near the Spine, upon the left fide of the Great 
 Lobe, and ( is of a Pyramidal form, projecting like a Nippie, at 
 the fmall Curvature of the Stomach. 
 
 Th e Lobulus Caudatus, which is merely the root, or one of the 
 angles of the Lobulus Spigelii, advancing towards the middle of 
 the lower fide of the Great Lobe. 
 
 The Lobulus Anonymus , or Sluadratus, which is placed between 
 the palTage of -the round Ligament and the Gall-bladder, and is 
 lefs prominent, but broader than the former Lobule. 
 
 From the Lobulus Anonymus, abridge called Pons, or IJlh- 
 mus Hepatis, runs acroi's the PalTage for the Round Ligament, to 
 be joined to the Left Lobe : — It is fometimes awanting. 
 
 Upon the under fide of the Liver, there are feveral Fiffures , of 
 which the following are the principal. 
 
 The Great Fijfure, called Foffa Umbilicalis, between the Right 
 and Left Lobes, at tile under and tore part of the Liver. 
 
 This is terminated by a Notch at the fore-part of the Liver,— 
 of different depths in different bodies,— and behind, it is com- 
 monly covered with the Bridge above mentioned. 
 
 The Principal Fiffure, termed Sulcus Tranffoerfus, or Sinus 
 Fortarum, extending from right to left, between the Great and 
 Small Lobes, and bounded by thefe Lobes at its extremities, and 
 by the Lobulus Anonymus before, and by the Lobulus Spigelii 
 behind, the two latter forming parts compared by the An- 
 cients to a Gate, and therefore called Porta. 
 
 The Deprejfion between the Great Lobe and Lobulus Spigelii, 
 for the palTage of the Inferior Vena Cava, which has frequently 
 a bridge over it, forming it into a Canal. 
 
 A Small Depreffion, called Foffa DuN us Venofi, between the 
 | Left Lobe and Lobulus Spigelii, running a little obliquely from 
 I right to left fide, and receiving a Ligament,— which is a Branch 
 I of the Umbilical Vein in theFcetus. 
 
The Liver is conneEled to the Body by different Procejfes, 
 termed its Ligaments, all of which, excepting one, are formed by 
 doublings of the Peritoneum, viz. 
 
 The Ligamentum Latum, or Sujpenfirium Hepatis, placed be- 
 tween the Right and Left Lobes above, and extending below into 
 the FofTa Umbilical, is. 
 
 It is fixed obliquely to the Diaphragm and tip of the Enfiform 
 Cartilage, and then del'cends in the fame oblique direElion, ad- 
 hering to the inner part of the Vagina of the Right ReElus Abdo- 
 minis Mufcle, as far as the Umbilicus. 
 
 The Ligamentum Rotundum, — which is the Umbilical Vein in 
 the Foetus, placed in a doubling at the under part of the Liga- 
 mentum Latum, and fixed to the Umbilicus. 
 
 Thefe two Ligaments have been fuppofed to refemhle a Falx, 
 with the edge turned uppermoft, from which circumftance the 
 Ligamentum Latum is fometimes alfo called Falciforme. 
 
 The Ligamentum Dextrum, or Right Lateral Ligament, which 
 is fhort, and conneEls the back-part of the right extremity of the 
 Great Lobe to the Diaphragm. 
 
 The Ligamentum Sinifirum, or Left Lateral Ligament, which 
 is longer than the former, and conneEls the left extremity of the 
 Small Lobe to the Diaphragm. 
 
 The Ligamentum Coronarium, confidered by fome as merely 
 Cellular Subftance, and by others as a refleElion of the Peritone- 
 um, or both. — It unites the root of the Liver to the Tendinous 
 Portion of the Diaphragm. 
 
 Befides the Ligaments already mentioned, two others are de- 
 fcribed by Haller ; one called Hepatico-colicum, which paffes 
 from the Gall-bladder and contiguous Sinus Portarum, acrofs 
 the Duodenum, to the Colon ; another called Hepatico-renale , 
 which defcends from the root of the Liver to the Kidney.— 
 Thefe, as well as the other Ligaments of the Liver in gene- 
 ral, are produElions of the Per itoneum. 
 
 The Ligaments of the Liver- preferve it in its proper fituation, 
 and of courfe prevent it from inditing too much in any dirt Elion. 
 The Stomach and Inieftmes fupport it when the Body is upright 
 and the Diaphragm, when the Body s inverted. 
 
 The Liver has a Ample Coat adhering clofely to it which it de- 
 rives from the. Peritoneum, and is every where covered by this 
 Membr ane, excepting behind, where it adheres to the*Diaphragm 
 by Cellular Subifance. 
 
 The Subftance of the Liver is eom ofed of feveral kinds of 
 Veffels, the extreme Branches of which are intermixed in fuch a 
 manner, as to form numberlefs Pulpy Corpufcles, named Acini, 
 from a refemblance to finall Stones or Kernels of Fruit, which 
 when minutely examined, are obferved to be compofetl of Veflels 
 in the form of radiated Villi or Penicilli. 
 
10 ® 
 
 The Vejfels of the Liver are, the Hepatic Artery, Vena Porta- 
 rum, Vena llcpatica , Abforbents, and Biliary Duels. — It has 
 iikewife numerous Nerves. 
 
 The trunks of the Hepatic Artery, Vena Portas, Biliary Dufls, 
 and Nerves, with the Abforbents and Lymphatic Glands of the 
 Liver, form a large Cord at its under part. 
 
 The Artery is fituated in the left part of the Card, the Vein 
 in the right, with the Trunk of the Biliary Dufls before it 
 the Nerves and Lymphatics furrounding the great Veflels. 
 
 The Cord of Veflels and Nerves is intermixed with moch Cel- 
 lular Subftance and covered externally by a reflection of the Pe- 
 ritoneum, which has obtained the name of Capfule of G lisson. 
 
 The Brandies of Veflels and Nerves accompany each other- 
 through the fubftanceof tire Liver, forming fmall Fafciculi, in 
 a manner fomewhat fimilar to that by which the Cord is formed 
 by their Trunks. 
 
 In their courfe through the Liver, the Branches of the different 
 Veflels and Nerves, but particularly thofe of tli£ Vena Portae, are 
 inclofed in a large portion of Cellular Subftance, which is alio 
 frequently called Capfule o/Glisson, from that Author fuppo- 
 fing it to be a continuation of the Capfule which covers the Vef- 
 fels before they enter the Liver. 
 
 The Hepatic Artery is derived from the Caeltac, and is difpsrfed 
 throughout the whole fubftance of the Liver, and alfo upon the 
 Coat which covers it, and is fo fmall when compared with the 
 bulk of the Liver, as to have been generally l'uppofed to be def- 
 ined for the nourifhment merely of that Vifcus ; but from in- 
 jed ons palling from the Artery to the Biliary Duffs, and from 
 other c a ufe;-, it has been l'uppofed by fotne Anatom ills, that the 
 Hepatic Artery is not only intended to nourilh the Liver, but is 
 capable of fecreting part of the Bile ; — and this fuppolition is 
 farther confirmed from the Vena Porta; having, in a recent cafe 
 been found awanting, while, at the fame time, the Hepatic Ar- 
 tery -vus larger than ufual, and the Veins which commonly form 
 the Vena Portae, terminated in the Vena Cava. 
 
 The Vena Porta is named from its iittmion with l efpeff to the 
 Porta of the L’ver. 
 
 It partakes of the nature of an Artery and a Vein Like the 
 former it^carries the Blood from the Trunk to the Branches, and 
 like the latter, it carries it ro the Heart; — or it is peculiar in' the 
 Blood, m one part flowing from theBranches to the Trunk and 
 in another from the Trunk to the Branches. 
 
 It is formed by the Veins of the Stomach and Inteftines, joined 
 to thole of the Spleen, Omentum, and Pancreas, and ap- 
 proaches to the nature of an artery in the thicknefs of its Coats 
 tnougn it has no puliation. 
 
 It p.tffes to the Porta, where, from Its great flze, it is named 
 iiuus of the,Vena Port®, and divides into Branches which ?c 
 Vox., n. K 
 
1 10 
 
 company thofe of the Artery in their courfe through the fub Gance 
 of the Liver, terminating at lad in the Pulpy Corpufcles. 
 
 The Vena Porta Li ves to carry Venous Blood* to the Liver, 
 for the fecretion of the Bile. 
 
 The Vena: Hepatic# are numerous. They are reflected partly 
 from the extremities of the Artery, and partly from thofe of the 
 Vena Pori®. 1 hey unite by degrees, and accompany the other 
 two fets of Vdfels ; but at the root of the Liver they form two or 
 three large Trunks which terminate in the Vena Cava, where it 
 h about to perforate the Diaphragm. — They likewife fend off 
 feme final 1 Branches which terminate in the Cava, where that 
 Vein lies behind the Liver. 
 
 The Venae Hepatic® receive the Blood from the Hepatic Ar- 
 tery and Vena Port®, after the Bile has been fecretcd, and return 
 it to the Vena Cava, to be conveyed by it to the Heart. 
 
 The lymphatics of the Liver are fo numerous as to cover al- 
 molt the whole of its outer Surface. They difcharge their con- 
 tents, partly intd'the beginning of the Thoracic Duff, and partly 
 to a Plexus fituated in the- fore-part of the Thorax. 
 
 The Nerves of the Liver are alfo numerous. They ai ife from 
 the Great Syrr.pathctics and Eighth Pair, and accompany the 
 Blood-veffels. 
 
 The Biliary Duels aVife by extremely- minute Branches, termed 
 Fori Bilarii or Tubuli Biliferi, chiefly front the extremities of the 
 Vena Port®, in the SuDltance of the Corpufcles, through the 
 whole of the Liver. 
 
 The Pori Bilarii run in company with the Branches of the Ar- 
 tery and Veins, and unite into larger and larger Branches, which 
 afterwards go into two, and thd'e again into a fingle Tiunk in 
 the Sinus Portarum, called Du'S us Hepaticus . 
 
 Tite DuShis Hepaticus ferves to carry "The Gall or Bile, which 
 is of a yellow green colour, from the Liver, — and to convey it 
 by the power ot the Heart, Hepatic Artery, and Vena Pori®, 
 alTifted by the preffure of the furrounding Mul'cles, to the Duo- 
 denum, and partly to the Veficula Fellis. 
 
 The Veficula, or Cyjlis Fellis, or Gall-bladder , is a fmail ob- 
 long, Pyriform Bag, confiding of a Bottom, Body, and Neck, 
 fituated upon the concave fide of the Great Lobe of the Liver, 
 and placed in a tranfverfe direction from belvnd forwards. 
 
 It extends fiom the Sinus Portarum, where the Neck is fitu- 
 oted, to the anterior edge of the Liver, and when full advances 
 beyond the edge of the Liver, fo as fometimes to have its Fun- 
 dus oppofed to the fofc parts of the Abdomen, under th? edge of 
 the Falfe Ribs. 
 
 The bottom is a little lower than the Neck, when the Body 
 is in the erect pollute. It inclines alfo a little to the right 
 tide, and refls upon the Colon at the beginning of the Duo- 
 denum. 
 
Ill 
 
 It is compofed of feveral Coats, the external of which is nr 
 continu r.To.i of the Membrane of the Liver : i his however, is 
 on. ' ,. rartiai Coat covering that part of th$ Gall-bladder, which 
 prop. cts neyohd the Surface of the L.ter. — It iiiv.es to give 
 it' . ih to the Gall-bladder, and to fix it to the Liver. 
 
 o er the former Coat, a few pale featured Fiores, running 
 i,i V inous directions, are fometimes oblerved, which have been 
 c.ididered as a Ahtfcul'ar Coat ; and under this is a fin all quanti- 
 le of Cellular Subltance, which has obtained the name of Ner- 
 vous Coat , 
 
 ' lit Inner Coat, fometimes called Fillous., is. full of finall Re- 
 ticular Rugae or Folds, which become extremely minute towards 
 the CervcX, where they run in a longitudinal direction. 
 
 The Surface of th s Coat is every where perforated by the 
 Ducts of final 1 Follicles, which diicharge a vilcid Mucus, to de- 
 fend the Suifaceof the Inner Coat from the Stimulant natuie of 
 the Bile. 
 
 The Gall- Bladder is connected through its whole length to 
 the Liver by Cellular Sublfance, Blood- velfels, and Abforbenis, 
 among which the Hepato-cyJHc Dull, limilar to thole round in 
 many Animals, were in former times delcribed, and iuppofed 
 to carry the Bile found in the Gall-bladder immediately from the 
 Liver. It is now fufficiently afeevtained, — that no iuc’n Dufts 
 txilf in the Human Body. 
 
 The Gall-Bladder has Blood -refill?, abforbents, and Nerves, 
 in common with thole of the Liver.— Its Veins pafs into the Vena 
 Portae. 
 
 The Neck of the Gall-bladder is twifted and folded againft it- 
 fe If, and afterwards con: rafts and lends out a Duct called CyJiicuj, 
 which runs near the Dtifius Hepaticus , and then joins it, to form 
 the Duffles Communis Ctoledochus . 
 
 The Duffus Cijiicus is fmalier than. the Dtiffus Hepaticus, and 
 differs from it allbin having a number ef imperteft Partitions or 
 Plica', running in a femewhat fpiral direction, and forming it in- 
 to Cells which retard the flow of the Bile. 
 
 The Gall-bladder ferves as a receptacle for the Bile, when the 
 Stomach and Inteffines are empty and have no need of it, and re- 
 tains it till wanted for the purpofe of digellion. — It is afterwards 
 difeharged from the Gall-bladder, when the Stomach is full, in- 
 to the Duftus Communis, and from that to the Duodenum, 
 chiefly by the preflfure of the furrounding Vifceva, and partly as 
 fame Anatomilis fuppofe, by a contraftile power in the Gall-blad- 
 der iifelf. 
 
 The whole of the Bile contained in the Gall-bladder is found, 
 by experiment, to pafs from the Liver through the Hepatic Duft 
 to the Duftus Communis, and from that by the Cyclic Duft into 
 the Gall-bladder. , 
 
 The Bile returning from the Gall-bladder is cbferved, from 
 the thinner parts being abforbtd, to be thicker,, mere aciid and 
 
Liver. 
 
 The DuSus Communis C.boledochus, called Choledochiis,S rum its 
 conveying Biie, is about the iize of a Goofe-quii], an .d is con- 
 siderably larger than either of theDufts which open into it. 
 
 It dei'cends at the pofterior and left part of the Duodenum, and 
 pafl’es for 1'orcie way obliquely between the Mulcular and Inner 
 Coats of that Gut, — the obliquity anfvvering the purpofe of a 
 Valve. 
 
 It terminates in the left, pofterior, and near to the under part 
 cf the I’econd Turn of the Inteftine, by a projecting Orifice, 
 which is rounded above, and pointed below. 
 
 The Stt ufture of the Duilus Chcledochus, and of the Biliary 
 Du£ls in general, is of the fame nature being entirely Membra- 
 nous : The Inner Surface of the Dufts alfo agree in being per- 
 forated by numberlel's pores, winch are the Mouths of Mucous 
 Follicles, fimilar to thole upon the infide cf the Gall-Bladder. 
 
 The Bile ferves to mix t he different parts of the Food properly 
 together, for the foimation of the Chyle, — to correct too great 
 a difpofition to acidity, — and to excite the Perilfalic motion of tlie 
 Inttlfir.es, 
 
 SPLEEN. 
 
 The Spleen is a foft and very Vafcular Subfiance, and of a 
 purple colour. 
 
 It is fomewhat deprtlTed, is of a long oval form, and of a con- 
 fiderable fize, but varying in this refpefl in different fubje&s. 
 
 It is (ituated in the Left Hypochondriac Region, between the 
 laige extremity of the Stomach and correfponding Falfe Ribs; — 
 It sounder end lying behind the Colon, and over the top of the 
 Left Kidney. 
 
 The fu nation of the Spleen varies a little, according to the 
 (late of Refpir-tion, and to the fullnefs or emptinefs of the Sto- 
 mach ; — riling or failing as the Lungs ate lels or more dilated, 
 and becoming more oblique in its iituation,— with its inferior ex- 
 tremity turned more forwards, — in proportion as the Stomacn 
 becomes more diftended. 
 
 Its External Surface is convex and uniform, like that of the 
 Ribs, &c. to which it is oppofed. 
 
 Its Internal Surface, or that next the Spine, is irregularly 
 concave; and is divided into an Anterior and Pofterior Plane, by 
 a longitudinal Groove or Fifl'ure, where the Veffels and Nerves 
 
 enter. . 
 
 The Anterior Plane is more concave than the Pofterior, ccr- 
 refponding to the contiguous convexity of the Stomach. 
 
 The SpTeen has frequently deep Fiffures upon its edges ;— fume- 
 times it has ltnall /Ippendages attached to it, and not unfieouent- 
 ly there is one or more Small Spleens connetfed with it. 
 
113 
 
 At the under fide, it is fixed to the Omentum, and, by means 
 of that and Blood- veffels, to the Stomach and Pancreas.— -Be- 
 hind, it is connedted to the Diaphragm ; and below, to the Lett 
 Kidney and Colon, by refledlions of the Peritoneum, and by 
 Cellular Subftance. 
 
 It is covered by a double Membrane, one Layer of which is a 
 production of the Peritoneum, the other proper to the Spleen it- 
 felf j but fo clofely connedled to the common Coat, that they ap- 
 pear to be one and the fame Membrane. 
 
 The fubftance of the Spleen is remarkably foft, and is by 
 much the mod tender of the Abdominal Vifcera. 
 
 It confifts of a Congeries of Blood-vefl'els, Lymphatics, and 
 Nerves, joined together and fupported by a large quantity of Cel- 
 lular Subftance. 
 
 The extreme Branches of the Blood-vefi'els put on the appear- 
 ance of Penicilli, or fmall Brujhes, which have been miftaken 
 for Glands. 
 
 Thefe VelTels are fo tender, that when an injection is forcibly 
 thrown into either Artery or Vein, it burlts into the common 
 Cellular Subftance, and gives the appearance of Follicles or 
 Cells. 
 
 The Blood-veJJ'els of the Spleen are among the largeft of the 
 Body, in proportion to the Vilcus on which they are dil’perfed. 
 
 The Artery is a principal Branch of the Caeliac. — It runs in a 
 ferpentine direction, and, after fending Branches to the Pancre- 
 as, &c. and the Arteria Breves to the left end of the Stomach, 
 it goes into the fubftance of the Spleen, where it is fubdivided in- 
 to Branches, which are crowded together, and run in every direc- 
 tion, forming at length Plexus and Penicilli, which terminate in 
 the Branches of the correfponding Vein. 
 
 The Vein, like that in molt other Vifcera, is larger than the 
 Artery: — It receives the Blood immediately from the termi- 
 nations of the Artery, without the intervention of Ceils. 
 
 The Splenic Vein receives the Vena Breves of the Stomach, the 
 Pancreatic Veins, & c. and forms one of the principal Branches 
 ot the Vena Porlx. 
 
 The Lymphatics from the fuperficial parts of the Spleen join 
 the deep Laied Abforbents at the Filin re where the Biood-veffels 
 enter, and afterwards pits through feveral Conglobate Glands 
 lying over the Splenic Artery. 
 
 They intermix with Lymphatics belonging to feveral other 
 Vilcera, and terminate in the Thoracic Duff. 
 
 The Nerves of the Spleen, which are i’m.ill, but confiderable 
 in number, are Branches of the Great Sympathetic and Eighth 
 Pair, and form an irregular Plexus which furrounds the Veflels. 
 
 No Excretory Duff has been found to proceed from the Spleen, 
 in confequenc| of which very various opinions have been enter- 
 tained with refpefil tc the nfe of that Organ. 
 
 Yol. II. K id 
 
Many of the ancients were of opinion,— that befides the Bile 
 of the Liver, there was an Atra Bills, or Black Bile, and that 
 the Spleen was the re.cepticle of the latter. 
 
 Others have thought a particular Menflruum was fecreted in it, 
 and conveyed to the Stomach for the purpofe of digeftion. 
 
 Others again,— that the Blood of the Spleen promotes the flug- 
 giflr circulation of the Blood of the Vena Portae. 
 
 The late Mr. Hewson, who has written particularly on the 
 Spleen, was of opinion it concurred with the Thymus and Lym- 
 phatic Glands, in forming the red Globules of the Blood, and 
 that thele Globules were rendered complete in the Spleen. 
 
 It h as been alfo fuppofed,— that as the Stomach becomes full, 
 the Spleen is compreffed by it, in confequence of which a greater 
 quantity of Blood is fent to the Pancreas, for the Secretion of 
 the Pancreatic juice. 
 
 But the prefent moll prevalent opinion is,— that the Blood un- 
 dergoes fome change in it, which renders it ufeful in the fe- 
 cretion of the Bile and the opinion is fupported from the 
 great quantity of blood with which this Organ is known to be 
 fupplied, and from its Vein, not only in Man, bet in other ani- 
 mals, palling to the Vena Portae. 
 
 PANCREAS. 
 
 The Pancreas, i. e. AllFleJh , or the Sweat Bread, is a long 
 flat Gland of the Conglomerate kind, and of the fame nature 
 with the Salivary Glands, of which it may be reckoned the 
 largeft. 
 
 It is lituated in the Epigaftric Region, and is placed tranfverfe- 
 ly in the back-part of the Abdomen, between the Stomach and 
 Spine. 
 
 It has a large or Right Extremity, and a Small or Left one, an 
 Anterior and Pofterior Surfaee, and an Upper and Under Edge. 
 
 The Right Extremity is attached to the left fide of the Second 
 Turn of the Duodenum, or to that part where the Inteftine is 
 about to go acrofs the Spine. 
 
 From the under part of the Right Extremity, the Pancreas 
 fends down an Elongation or Procefs, which adheres clofely to 
 the Duodenum. 
 
 This Procefs was difeovered by Winslow, and termed by 
 him Pancreas Minus. — It is alfo called Head of the Pancreas. 
 
 The Body of the Pancreas palfes before the upper part of the 
 tranfverfe portion of the Duodenum, and over tire Aorta, Vena 
 Cava, and part of the Splenic Velfels, to all of which it is at- 
 tached. 
 
 The fmall extremity, which is rounded, is fixed to the Spleen, 
 through the medium of the large Omentum. 
 
 The Pancreas is covered anteriorly by the two Layers of the 
 root of the Mefo-colon 5— pofteriorly, it is only covered with 
 Cellular Subfiance, which conneas it to the Vertebras 
 
It is composed of Acini, which form fmall Glands or Lobes ; 
 and thefe are connefted loofely by Cellular Subftance,^n fuch a 
 manner as to give an appearance of uniformity and lihosthnefs 
 to the External Surface. 
 
 The Arteries of the Pancreas are derived, partly from the He- 
 patic, but chiefly from the Splenic, by f'everal fmall Branches, 
 which pafs at various places into its Subftance, in a tranfverfe 
 direftion. 
 
 The Feins correfpond in name and courfe with the Arteries, 
 and aflift in forming the Vena Portae. 
 
 The Lymphatics run to the Splenic Plexus, and terminate in 
 the Thoracic Duft. 
 
 The Nerves of the Pancreas are fmall : Like thofe of the o- 
 ther Vifcera of the Abdomen, they are derived from the Great 
 Sympathetic and Eighth Pair. 
 
 From the different Acini of the Pancreas, fmall Duffs arife, 
 which join into larger ones running tranfverfely in the Subftance 
 of the Pancreas, and forming a common Duff, called Duflus 
 Pancreaticus. 
 
 The Pancreatic Dud, termed alfo Duiius Wirtsungi, after 
 the difcoverer of it in the Human Body, is remarkably thin, of a 
 white colour, and femi-tranfparent. 
 
 It begins at the Left Extremity of the Pancreas, runs in the 
 fubftance of the Gland, a littlh below its middle height, and be- 
 comes gradually larger in confequence of receiving tiie different 
 Branches which compofe it,— and is at laft about the fize of a 
 Raven’s-quill. 
 
 At the Right Extremity of the Pancreas, it receives the Prin- 
 cipal Duft of the Pancreas Minus, and terminates obliquely in 
 the Duodenum along with the Duftus Communis Choledochus. 
 — In fome rare cafes, however, it terminates at a little diffance 
 from the Biliary Duft; and fometimes alfo, the Duff of the Pan- 
 creas Minus ends feparately in the Duodenum. 
 
 The Pancreas fecretes a Liquid or 'Juice, refembling Saliva 'in 
 quality and appearance, and difcharges it by its Excretory Duft 
 into the Duodenum. 
 
 The Pancreatic Juice incorporates the Bile with the Alimen- 
 tary Mafs, and may be faid alfo to anfwer the fame purpofe to the 
 contents of the Inteffines, which the Gaftric Juice does to ihofe 
 of the Stomach ; — or, it finifhes that digeftive Procefs in the In 
 teftines which was begun in the Stomach. 
 
116 
 
 OF THE 
 
 ORGANS OF URINE AND GENERATION 
 
 IN THE MALE. 
 
 KIDNEYS. 
 
 The Kidneys are two Glandular bodies, of a pale red colour, 
 fituated in the upper and back-part of the Abdomen, in the Lum- 
 bar Region. 
 
 They are placed one on each fide of the Spine, extending from 
 the Eleventh Pair of Ribs to near the Ofia Ilia ; and reft upon 
 the Diaphragm, large Pfoae, Quadrati Lumborum, and Tranf- 
 verfales Abdominis Mufcles. 
 
 The Right Kidney is fituated at the under and back-part of 
 the large Lobe of the Liver, behind the Colon, and is common- 
 ly a very little lower than the left. 
 
 The left Kidney is placed at the under and back-part of the 
 Spleen, and behind the left parts of the Stomach, Pancreas, and 
 Colon. 
 
 The Kidney is about five or fix fingers -breadth in length, but 
 confiderably let's from the outer to the inner fide, and lefs than 
 that ftii) from before backwards; or, it is compared in ftiape to 
 a French or Kidney bean. 
 
 It is rounded anteriorly, flattened pofteriorly, convex and uni- 
 form at its outer margin, and has a deep deprefiion or Sinus to- 
 wards the Vertebrae, furrounded with unequal edges, where the 
 Renal Veflels and Nerves enter. 
 
 It is a little broader behind than before, and a little broader 
 and more curved above than below, from which circumftanee, 
 but more particularly from the dilpofition of the Veflels to be af- 
 terwards mentioned, it is enfy to diftinguifh the Right from the 
 Left Kidney when taken out of the Body. 
 
 The Right Kidney is connected to the Liver and Duodenum, 
 the Left to the Spleen, and both to the Mufcles on which they 
 are placed, and to the Renal Glands and Colon, by Cellular 
 Subrtance and by the Peritoneum. 
 
 They are alfo conne&ed to the Aorta and Vena Cava by the 
 Blood-vefl'els, and to the Bladder of Urine by the Ureters. — 
 
117 
 
 They accompany the motions of the Liver and Spleen, in the dif- 
 ferent Hates of Relpiration. 
 
 Each Kidney is furrounded by loofe Cellular Subftanc#, which 
 commonly contains a confidera'ole quantity of Fat, from which 
 it is termed Tunica Adipofa . 
 
 The Tunica Adipofa covers not only the Kidney, but large 
 Veffds, and defends them from the prelfure of the furrounding 
 Vifcera. 
 
 Under the Tunica Adipofa, there is a Membrane campofed of 
 -the original proper Coat and Cellular Subliance incorporated, 
 which adheres clofely to the Kidney, and is rcflefled over the 
 edges of the Sinus, toLe joined to the Pelvis and large Veffels. 
 
 The fubltance of the Kidney is commonly fmooth and uni- 
 form, though fometimes it is irregular, in coniequence of the 
 Lobes which originally form it not being completely incorpora- 
 ted. — It conlifls of an outer part called Cortical, and an inner 
 termed Medullary. 
 
 The Cortical Subfancc, termed alfo Secerning, furrounds the! 1 
 Kidney, and forms about a third ;of its breadth ; — it likewife 
 fends in Precedes or Partitions, which feparate the Medullary 
 parts from each other. 
 
 The Medullary, termed alfo Uriniferous Subfance, is of a red- 
 der colour than the former, and is divided into a number of dif- 
 tinft Columns, each of which terminates in a proje&ion called 
 Papilla, or Procejfus Mammillaris* 
 
 The PapilLe are merely the continuation of the Uriniferous 
 part ; though frequently conlidered as a third division of the fub- 
 lfance of the Kidney. 
 
 Each Kidney has one, and fometimes more Arteries, which 
 run trar.fverfely from the Aorta, and a Vein ft; 11 larger, .which 
 terminates in the Cava. — They enterat the Sinus of the Kidney, 
 and are included in Cellular Subliance, which accompanies them 
 throughout their courfe. 
 
 The Right Renal Artery is longer than the Left, in confe- 
 quence of the Vena Cava, behind which it palfes, being placed 
 upon the Right Side of the Aorta. 
 
 1 he Artery, as it approaches the Kidney, is divided into 
 Branches, which are afterwards minutely d.ftributed through 
 the Cortical Subliance, forming Arches and Analtomofes ; — but 
 thefe are found to be much Id’s frequent than are commonly de- 
 feribed. 
 
 7 he fmall Branches, after turning and winding in var ous di- 
 reiSticns, pafs partly towards the Surface of the Kidney, where 
 they form irregular Stars, fonieof which fupply the proper Mem- 
 brane. 
 
 Others turn inwards in a waving direction, and form Corpuf- 
 cles, which are difpofed fomewhat after the manner of Clufsrs of 
 fmall Berries, which can only be feen diltinftly by the aliitlance 
 of Glades, after a minute injefiicn. 
 
The Corpufcles were eonfidered by Dr. Nichols as the Glo- 
 bular .termination of Blood-velTels, and termed by him Globuli 
 Arteriarum Termini-, — but thei'e Globuli were afterwards ob- 
 l’erved by Mr. Hewson to confift of final 1 Veffels intimately in- 
 termixed. 
 
 The Ve ins returning from the extremities of the Arteries unite 
 in the Cortical Subftance of the Kidney. 
 
 The Blanches of the Renal Vein are much larger than thole 
 of the Artery, but correfpoml with them in their courle. — They 
 form a large Trunk on each fide, which lies anterior to the cor- 
 refponding Artery, and runs tr.mfverfely to the Cava ; — the left 
 which is the larger of the two, parting acrofs the fore pai t of tl 
 Aorta, 
 
 The Lymphatics of the Kidney run from without i.nwards, and 
 terminate in the Lumbar Glands, and aftei wards in the Thora- 
 cic Du£t. — The Superficial Lymphatics are fo fmall, as Ibidem 
 to be feen, excepting in the difealeri it ate of the Kidney. 
 
 The Nerves aie from the Scmilunai Ganglion formed by the 
 great Sympathetic and Nighth Pair. They form a Plexus which 
 furrounds the Blood- vertels, and, accompanies them in the Kidney, 
 
 From the minute Extremities of the Renal Artery, in the Cor- 
 puicles feated in the Cortical Subftance, the Uriniferous Tubes 
 arife. They are mixed with fome extremely fmall Blood- veffels. 
 and conftitute the Medullary Subftance of the Kidney. 
 
 By degrees they unite into larger Tubes, which run in a ra- 
 diated manner, the direflion being from the outer edge or citcum- 
 fer?ncej towards ih? inner part or Cavity of the Kidney. 
 
 The radiated Tubes, becoming ftill larger in their pafl’age, ter- 
 minate in the Papilla ’, which are of a comprefled conical form, 
 and are at a little diftance from each other. 
 
 The Papilla are twelve or more in each Kidney, the number 
 varying according to that of the original Lobes of which the 
 Kidney is compoied, and likewife from fome of the Papillae be- 
 ing incorporated with each other. 
 
 Upon the points of the Papilla? are the terminations of the Ui i- 
 niferous Tubes, — large enough to be diltinguifhed by the naked 
 Eye, — through which the Urine diftils from the Subftance of the 
 Kidney. 
 
 Round the root of each Papilla, a Membranous Tube arifes, 
 termed Infundibulum or Calix, which receives the Urine from the 
 Papilla?. 
 
 The Infundibula are commonly the fame in number with the 
 Papilla? ; the number, however, varying in different fubje£ls, two 
 or more of the Papillae fometimes opening into the fame Infundi- 
 bulum. 
 
 The Infundibula join into two or three larger Trunks, which 
 afterwards form a Dilatation of confulerable llze, of the fttape of 
 an inverted Cone, and termed Pelvis of the Kidney. 
 
119 
 
 The Pel-vis is placed partly within, but the greateft part of it 
 without the body of the Kidney, and contrails into a long Tube, 
 about the fize of a Writing-pen, called Ureter. 
 
 The Ureters are commonly one to each Kidney, though in 
 fomc rare inftances they are double on one or on both Tides. 
 
 The Artery of the Kidney is placed uppermoft, — the Vein in 
 the middle and fore-part,— and the Pelvis and beginning of the 
 Ureters at the under and back-part of the Blood-veffels. 
 
 The Ureters delcend obliquely inwards behind the Perito- 
 neum, and go over the great Pfoae Mufcles and Iliac Veffels, op- 
 pofite to the anterior and lateral parts of the Os Sacrum. 
 
 They pafs afterwards into the Pelvis, and terminate in the un- 
 der, outer, and back-part of the Bladder. 
 
 In their defeent, they are not ftraight, but form turns which 
 are commonly compared to the Italic neither are they cylin- 
 drical, as they form night dilatations and contractions in their 
 courfe, two of which contraflions a;e more obfervable in their 
 paffage over the Pfoae Mufcles, and at their infection into the 
 Bladder. 
 
 The Ureters are covered anteriorly by the Pertoneum, and 
 compofed of an External Membranous Coat , a middle Mufcuiar 
 one, formed chiefly of circular Fibres, and an Internal Coat , 
 fometimes called Villous. 
 
 The Inner Coat is very Vafcular, and is perforated hy'the 
 Mouths of fmall Du6ls, which line it with a Mucus to defend it 
 from the Urine. 
 
 The Veffels and Nerves of the. Ureters are from thofe of the 
 contiguous parts. 
 
 The Ufe of the Kidneys is to fecrete the Urine from the Blood, 
 and couvey it by means of the Ureters tu the Bladder. 
 
 RENAL GLANDS. 
 
 The Renal Glands , termed alfo Capfula: Atrabilaritr, Capfula 
 Renales, Renes SUccenturiati, and Glandulee Suprarenales, are two 
 final!, flat. Glandular-like bodies of a dark-yellow-colour, ly- 
 ing in the upper and back-part of the Abdomen. 
 
 They are lituated at the upper, inner, and fore-part of the 
 Kidneys, over the large Pfoae Mufcles and Diaphragm, and high- 
 er than the Renal Veffels. 
 
 They are of an irregular figure, and are about a couple of fin- 
 gers-breadth in length, but much larger, proportionally, in the 
 Foetus han in the Adult. 
 
 The Right one is connected to the Liver, the Left to the Spleen 
 and Pancreas, and both to the fmall Mufcle of the Diaphragm, 
 and to the Pfose Mufcles and Kidneys, by Cellular Subftanc'e. 
 They are likewile retained by numerous Veffels and Nerves which 
 aie fpread over them. 
 
120 
 
 They are furrounded by Cellular Subftance, which is part of 
 the Tunica Adipofa of the Kidneys, and have a thin proper Coat, 
 wh’ch adheres firmly to them. 
 
 They are frequently obferved to be hollow, and to contain a 
 dark-coloured Bilious-like matter, which is confidered by many 
 Anatomifts as the Internal, very Vafcular and tender parts melted 
 down by putrefaction. 
 
 Their Arteries come from thofe of the adjacent parts, particu- 
 larly from the Renal, and alfo from the Aorta, and Diaphrag- 
 matic Arteries. 
 
 Of the principal Veins, the Right goes to the Vena Cava, and 
 the Left to the Renal Vein. 
 
 The Lymphatics go chiefly to thofe of the Kidneys. 
 
 The Nerves come principally from the Renal Plexus. 
 
 They have no Ex- retory Du£ts. 
 
 The Renal Glands have been l'uppofed to furnilh Lymph for 
 the dilution of the Blood returning in the Renal Veins, after the 
 discretion of the Urine; 
 
 Or, — to reftore to the Blood of the Vena Cava the irritable parts 
 which it lofes in the l'ecretion of the Urine and Bile ; 
 
 Or,-— to convey fomething ufeful to the Thoracic Duff ; 
 
 Or, in the Foetus,; — to divert-the Blood from the Kidneys, and 
 thereby leflen tide quantity of Urine. 
 
 But their ufe is ltill undifcovered ; though it is fuppofed from 
 their vicinity to the Kidneys, not only in Man, but in many o- 
 ther animals, that they are fubfervient to tilde Organs, and par- 
 ticularly to thofe of the Foetus. 
 
 VESICA URINARIA. 
 
 The Vefica Urinaria , or Bladder of Urine, is a large Sac fitu- 
 ated in the Pelvis of the Abdomen, in the bottom of the Hypo- 
 gaftric Region. 
 
 It is placed in the fore-part of the Pelvis, behind the Oft'a Pu- 
 bis, and before the upper, and above the under portion of the In- 
 teftinum RcClum. 
 
 When empty, it is contracted into a final] fize, which occupies 
 the underand fore part of the Pelvis; but, when fully diltended, 
 it rdes above the brim of that Cavity, and fometimes afcends to 
 within a little diftance of the Umbilicus. 
 
 When moderately dilated, it is of a roundifh, or irregular ob- 
 long form, but a little flattened before, more convex behind, and 
 broader at its anterior and pofterior, than towards its lateral 
 parts, — a little more capacious, alio, below than above, efpecially 
 at its pofterior part. 
 
 It is dillinguilhed into Fundus, Body, and Cer-vix, the fuft of 
 which is placed upwards and a little forwards ; — the l.ifl at the un- 
 der and fore- part. 
 
121 
 
 It is connected below to the Reflum, and at the Tides to the 
 Pelvis by the reflefted Peritoneum and Cellular Subftance, the 
 former of which, when the Bladder is empty, has the appearance 
 ef lateral Ligaments. 
 
 It is attached, at the fore-part of its Body, by Cellular Sub- 
 ftance, to the Ofl'a Pubis, without the intervention of the Perito- 
 neum. 
 
 It is alfo fixed to the Umbilicus by three Ligaments fituated 
 between the Peritoneum and Abdominal Ivlufcles. — They are 
 formed of the Urachus running upwards from the Fundus, and 
 the ftu ivellcd Umbilical Arteries palling obliquely from the fides 
 of the Bladder. 
 
 The firmed connexion is by means of a Ligamentous expan- 
 sion, which runs from each fide of the Neck of the Bladder and 
 Proftate Gland, to be fixed to the infide of the Arch of the Ofia 
 Pubis. — It is connected, aifo, at this p ace, to the Penisj' by the 
 Urethra. 
 
 It is compoftd of different Coats joined together by Cellular 
 Subftance, the firfit of which is only a partial one dontinued from 
 the Peritoneum. 
 
 The Peritoneal or Common Coat, recedes from the Abdominal 
 Mufcles at the top of the Pubes, and palfea over the Superior, and 
 clown upon the porterior and lateral parts cf the Bladder, to near 
 the termination of the Ureters, where it is about a finger’s- length 
 from the Anus, — and is there reflefted upon the Refturn and 
 back part of the Pelvis. 
 
 When the bladder is much diftended, it carries the Peritoneum 
 with it, and leaves a fpace between that Membrane and the 
 Pubes, of fuch length, that an incifion has frequently been made 
 here, and large Calculi extracted from the Bladder, 'without pe- 
 netrating into the Abdomen, or wounding the Peritoneum. 
 
 The fecond Coat is termed Mufcular. — It is compofed of dif- 
 tinci Fleftry Fiores, interwoven with each other, and forming 
 Fafciculi. 
 
 The F.xternal Fibres run clmfiy in a longitudinal direflion, 
 and are connected, at the under and fore part of the Bladder, 
 with the Ofia Pubis. 
 
 More internally, are Fibres which run ir. all direflions, arid 
 are intermixed with each other in the form of Net-work. 
 
 The Mufcula^ Fibres are contrafted about the Neck of the 
 Bladder, and form what has been termed SphinBer Vejlcee •_ 
 thefe, however, are merely the continuation of the other Fibres. 
 
 The Mufcular Coat, by its contra&ioB, occafions the complete 
 evacuation of the Bladder. — The Fibres about the Neck of the 
 Bladder, by ailing leparately from the reft of the Mufcular Coat, 
 prevent the involuntary difeharge of the Urine. 
 
 The Cellular Subftance, under the Mufcular Fibres, is fre- 
 quently termed Nervous Coat. 
 
 Vol. II. L 
 
122 
 
 The Intier Coat, though often called Villous, is fmooth like the 
 iniide of the Peritoneum, and, though thin, is fo denfe as to pre- 
 vent the exfud.ition of the Urine. 
 
 This Coat is rendered fomewhat unequal by the projefling of 
 the Falciculi of the Mufcular Fibres ; and when the Bladder is 
 empty, it forms large wrinkles or Rugae. 
 
 The infide of the Bladder is very irritable, in eonfequence of 
 •which a delire to expel the Urine is occasionally excited. It is 
 lined, however, by a Mucus, difcharged from its Arteries, which 
 prevents it from being conftantljr ii ritated by that Fluid. 
 
 The under part of the Bladder is perforated by three Openings, 
 of which one is placed anteriorly, and two pofteriorly. 
 
 The Anterior Opening is the beginning of the Pnlfage called 
 Urethra, and is furrounded by the Neck of the Bladder. 
 
 It comes off aimoft at a right angle from the lower part of the 
 Bladder, wi tliout any tapering of that, Vifcus. 
 
 The other two openings are formed by the termination of the 
 Ureters, which run obliquely forwards and inwards, between 
 the Mufcular and Inner Coat of the Bladder. 
 
 They terminate in the Bladder at a little diftance from each 
 other, and at the fame ddtance behind the beginning of the Ure- 
 thra, each by a fomewhat oval Opening, which is more contract- 
 ed than the Ureter is immediately above it. 
 
 The Arteries of the Bladder corne from various fources, but 
 chiefly from the Umbilical and Pudenda Communis. 
 
 The Veins return to the Internal Iliacs : — They form a Plex- 
 us of confiderabie fize upon each fide of the Bladder. 
 
 The Lyhiphatics accompany the principal Veins on the Blad- 
 der, and, at the under part and fides, pafs into the Iliac Glands. 
 
 ' Xhe Nerves are Branches of the Great Sympathetic and Sa- 
 cral Nerves. 
 
 The Bladder receives the Urine from the Ureters by drops, and 
 fometimes by fmall thread-like ftreams or fquirts, till by its ac- 
 cumulated quantity and aciimony, it forces that Vifcus to con- 
 tract and expel it. 
 
 The Urine is expelled, partly by the contraflion of the Blad- 
 der itfel f, and partly bv the a£lion of the Abdominal Mufcles and 
 .Piaphrs gm.prtfilng the Intclfines again if the Bladder. 
 
 The frequency of the evacuation depends upon the fize and 
 fenfib.lity of the Bladder, upon the quantity of Urine fecreted, 
 and the degree cf acrimony it pofleffes. 
 
 TESTES. 
 
 The Tejlcs, formerly termed Didymi or Gemini, are two Glan- 
 dular Bodies floated in the Cavity of the Scrotum. 
 
 The Scrotum, which furniftVes an external covering to the 
 Te!?f s,'is a continuation of the common Integuments,. .has the 
 
123 
 
 fame Stru'Sure with the Skin in general, but is more plentifully 
 l'un plied with Sebaceous Follicles, has no fat in its Cellular Sub- 
 fta'nce, and is occafionall; relaxed and corrugated in a greater de- 
 gree than the Skin in the other parts of the Body. 
 
 Upon the Suiface of the Scrotum, there is a luperftcial, longi- 
 tudinal projecting Line, which divides it into two equal parts, 
 and has the name of- Raphe. 
 
 The in; er Surface of the Scrotum is lined with Cellular Sub- 
 ftance, winch is firmer and more Vafcular than in other places. 
 
 The Cellul r Subihuice of the Scrotum, in ccnfequenc'e of 
 its rednefs. Fibrous appearance, and fuppoled power of contrac 
 tion, has, by mr-iv Anatomifts, been considered as a Mufcje, and 
 C- lied Dartos . — This opinion, however, has of iate years been re- 
 jected. 
 
 The Cellular Sublhnce of the Scrotum involves each Teftf- 
 cle finglv, and forms a Septum or Partition between' the two, 
 which prevents AT or Water fiom palling readily from one fide 
 ef the Scrotum to the other. 
 
 The Vejj-'ds and Ncr-ves of the Scrotum are chiefly from thofe of 
 the neighbouring parts. 
 
 The Blood-velTels are Branches of the Pudendal and Fe- 
 moral. 
 
 The Lymphatics go moftly to the Inguinal, — but fome o-f them 
 accompany thofe of the Teftes to the Lumbar Glands. 
 
 The anterior part of the Scrotum derives Nerves from the 
 Lumbar, and the pofterior from the Pudendal Nerves. 
 
 The Scrotum affifts in fupporting and protecting the Teftes. 
 
 Under the Scrotum are two Membranes or Coats, proper to 
 each of the Teftes, the one termed' Vaginalis, the other Albuginea. 
 
 The "Tunica Vaginalis, named from its forming a (heath, is of 
 the fame nature with the Peritoneum, being originally a Procefs 
 of that Membrane, which in the Fcetus delcend, with the Tefti- 
 cle irom the Abdomen. 
 
 It forms a fhut Sac, which has no communication with any o- 
 ther part. 
 
 It inclofes the Tefticle, as the Pericardium does the Heart, and 
 lies loofe every where, excepting behind, where it is continuous 
 with the Albuginea. 
 
 It is confiderably larger than the Teftis which it inclofes, 
 reaching as far above and below it as to allow it a certain degree 
 of motion. 
 
 It is connected by its external Surface to the Cremafter Mu fi- 
 de, and partly, by means of that, to the inner Surface of the 
 Scrotum. 
 
 It afiifts the Cremafter in fupporting the Teftis, and, by being 
 conftantly moiftened within by a Fluid exhaled from its Surface, 
 and from that cf the Tunica Albuginea, it allows the Tefticle 
 to move eafily. 
 
124 
 
 The Tunica Albugineas fo called from ils white colour, is, like 
 the former Coat, a continuation of the Peritoneum, and inveits 
 the Body of the Tefticle clofely. 
 
 It is a thick, ftrong, denfe, and inelaftic Membrane, of a glif- 
 tening appearance. 
 
 It is lemarkably fmooth on the outfide, but internally it is 
 rough and unequal, adhering every where firmly to the Body of 
 the Teftis. 
 
 It covers both the Teftis and Epididymis, connefts them to 
 each other, gives ftrength to them, and condudts their Veflels 
 in the manner the Mefenteiy does thofe of the Inteftines. 
 
 a he Body of the Teftis is of a yellowifh colour, and has a Pul- 
 py appearance, — is of an oval form, a little flattened at its outer 
 and inner Surface ; — and frequently one Tefticle is a little larger 
 ihan the other. 
 
 . The Tell es are placed obliquely, with one end upwards and 
 forwards, and the other end backwards and downwards. 
 
 At the outer and back-part of the Teftis, there is an Appen- 
 dix named Epididymis, from its fituation upon the Teftis or Di- 
 dyrnis, which is inclofed in the fame covering with the Teftis 
 itfelf. 
 
 The Epididymis begins at the upper part of the Tefticle, im- 
 mediately above the entry of the Blood-veflels ; and this part of 
 it being large and of a round form, is termed Globus Major, or 
 Mead of the Epididymis. 
 
 In its defcent, it becomes fomewhat fmaller and flatter, and is 
 attached behind to the Body of the Tefticle, where the Blood- 
 veflels go in ; but forwards it is loofe, the Tunica Albuginea 
 dipping in this place, and forming a Cavity or Pouch. 
 
 The under part of it becomes more firmly attached to the Bo- 
 dy of the Tefticle, and forms the Cauda, or Globus Minor $ it is 
 then turned backwards upon itfelf, after which it fends out the 
 Excietory Duff of the Tefticle. 
 
 The Body of the Teftis has numerous Arteries, Veins, Abfor- 
 bents, and Nerves ; but is principally compofed of a collection 
 of minute, tender, elaftic Filaments, intricately convoluted, term- 
 ed T ubuli Seminijeri, or Fa fa Seminalia. 
 
 The Eubitli Seminijeri are difpoled in Fafciculi or Bundles, 
 between Partitions, which are formed of Blood-veflels and Cel- 
 lular Subllauce. 
 
 Thefe Septula- begin at the root or Nucleus, fituated at the 
 back-part of the Tefticle, fometimes termed Corpus Higbmori- 
 anum, and extend in a radiated manner to the Tunica Albu- 
 ginea. 
 
 The Teftis is fixed behind by its Veflels, which are codcCled 
 into a Cord termed Spermatic, but is loofe- and free before, to 
 prevent it from being pinched. 
 
125 
 
 The Spermatic Cord, properly fo called, extends from the Ring 
 of the External Oblique Mufcl'e to theBody of the Tertis, and is 
 compoled of the Trunks of the different Vtflfels belonging to the 
 Tefticle, and of a quantity of Cellular Sui iltance. — fhe Cord is 
 covered by the Creniafter Mufcie $ and within this, by the Cine 
 Procefs of the Peritoneum which forms the Tunica Vaginal's 
 Tertis. This part of the Procefs, however, is lb ncorpcrated 
 with the common Cellular Subftance of the Cord, as o appear to 
 form part of it. : 
 
 The under part of the Vagina of the Cord is feparated by a 
 Partition formed by the upper end of the Vaginal Coat of the 
 Tefticle, and by condenfed Cellular Subftance, fo that no liquor 
 can pafs ealily from the Cord to the Tefticle, and mice merfa. 
 
 The Arteries of the Teftes, termed A ter 'ue Spermatic ee, and 
 Arteries Prepay antes, arife, one on each fide, from the fore-port of 
 the Aorta, a little below he Renal Arteries. 
 
 Fhe Spermatic Artery croftes over the Pfoas Mtifcie and 
 Ureter, and defeends, behind the Peritoneum to tiie under part of 
 the Abdomen. 
 
 At the lower part of the Abdomen, it perforates the Ring of 
 the External Oblique Mufcle, and paffes in the Spermatic Corel 
 to the Tefticle. 
 
 In its defeent, it gives blanches to the adjacent parts, and is 
 fo interlaced with thoie of the correlponding Vein, as to have been 
 fupp feu by the Ancients to have large lateral communications 
 with them. 
 
 After paifing the Ring, it divides into Branches which go to 
 the Eeftis at its porter for edge. They are partly difperfed upon 
 the Epididymis, but the larger Branches run in a ferpentine di- 
 rection into the Subftance of the Eeftis, where they are minutely 
 diftributed upon the Surface of the Seminal Tubes. 
 
 Belides the Spermatic Artery, there is a (’mailer one f. otn the 
 Hypogaftricy which accompanies the Vas Deferens, and is dif- 
 perfed along with the other Artery. 
 
 . The Veins are much larger than the c rrefponTng Arte- 
 iies, and have feveral Valves in them, efpecialiy without the Ab- 
 dumn. 
 
 I hey form a Plexus, which accompanies the Artery on each 
 fide, and is (bfnetimes called Corpus P amp y n fo r me, beiife com- 
 pared to the (hoots of the Vine, or Corpus Pyramidale , from giv- 
 ing a Pyramidal form to the Cord. 
 
 The Plexus a Rends m the Abdomen, and u -on the Surface 
 0 tu ' 1 Mulcle ; and abotit the part wheie it recedes f om 
 
 the Artery, n forms a (ingle Trunk, whi h, in die tight fide, 
 tei inflates in the Vena Cava, nearly oppofite to the Artery, and, 
 in the left hde, goes into the Renal Vein. 
 
 There is alio a (mall inferior Spermatic Vein, which accompa- 
 nies ns Artery, and ends in the Hypogaitric Vein. 
 
 VoL. 11. 
 
 L 2 
 
126 
 
 Tl'e Tubuli Seminiferi in the Body of the Tefiicle confift of 
 number ids extremely minute Dufts, which are of a Cylindrical 
 form, have no divifion into Branches, and when drawn out, are 
 found to be feveral feet in length. 
 
 They are fit It coiicfted into Bundles, between the Septulae of 
 the Tdt cle, and thele again into o.hers ft. 11 fmaller, e ch of the 
 fmallerdSeing. formed of a fimple Tube, coiled up into a Conical 
 form,' v it-li its Bale forwards, and its Apex towards the polterior 
 edge of the Teftlcie. 
 
 From the convoluted Seminal Tubes, an equal number of 
 ftraight VeffeF art lent out at the back, part of the Tefiicle, under 
 the name of Vafa Refla. 
 
 At the upper and back-part of the Tefticle, the Vafa Reffa 
 comrr.nnican , and form an irregular Plexus or Net- Work, called 
 Rete Vafculcfum lefts. 
 
 Tlte Rete lefts fends out from twelve to eighteen ftraight 
 Tubes, termed Vafa Eferentia , which carry the Semen from the 
 Tefticle to the Epididymis. 
 
 The Vafa Eferentia foon become convoluted, and form Coni- 
 cal Bunches, termed Coni Vafculofi. 
 
 The Coni Vafculofi are firmly conne&ed by Cellular Subftance, 
 and ate obferved by Dr. MOi\ro, in his Treatife De Eefibus , 
 to compofe fomewhat more than a third part of the Epididymis. 
 
 The Vafcular Cones gradually unite into a Angle Tube, which 
 conftitutes the reft of the Epididymis, and though only about the 
 fize of a Hog’s Briftle, tranfmits the whole of the Semen. 
 
 The fingle Tube becomes larger in irs coui fe and lefs convolu- 
 ted, and at laft, expanding its convolutions, it conies out greatly 
 incteafed in fize, and almoft in a ftraight direction, under the 
 name of Vac Deferens. 
 
 Befides the Duffs already defcribed, a Vas Aberrans is fome- 
 times obferved, which is one of the Valcular Cones, wandering 
 off, and terminating in the Epididymis lower than ufual. 
 
 At other times, the fame kind of Veflel forms a Procefus Cecils, 
 or blind Duff, with a dilated Extremity which does not com- 
 municate with any other part. 
 
 VESICULA2 SEMINALES AND PROSTATE GLAND. 
 
 The Vefcula Seminales are two fmall Pyriform Receptacles, 
 fituated between the under and lateral parts of the Bladder and 
 the Inteftinum RefUim,-— about three finge. s-breadth in length, 
 and the third part of that in breadth, ar.d a little flattened. 
 
127 
 
 They sre at a confiderable diftsnce from each other behind, 
 but anteriorly they converge, and become contiguous, forming a 
 fliarp angle. 
 
 Each of them is compofed of a convoluted. Tube, with irregu- 
 lar PrSCeJfits, and fi i rounded by a quantity of tough Cellular 
 Subilance, and by many Veffcls and Nerves. 
 
 Internally, they have a Villous appea^ ante and are formed of 
 irregular -€ef/s which correspond .with the ^ regularities on their 
 External Surface, and communicate freely with each other — 
 Their Hi ape, lize, and general appearance, however, vary indif- 
 ferent l'ubje£ts, and not unfrequently in the lame perlon. 
 
 Between the Veficuise Seminales, the ends of the Vaia De- 
 ferentia, now become larger and Cellular, pafs forwards till 
 they arrive at the Prollrate Gland, wlieie each Vas Deferens joins 
 the Veficula of that fide, and communicates lb freely with it, 
 that inje£led Fluids readily pafs from the one o the other. 
 
 From each Veficula Semmalis and Vas Deferens of the fame 
 fide, a fmall Canal , about a Finger’s breadth in length, p-.fles out 
 which is firmly connefted to its fellow, without communicating 
 with it, and becomes gradually fmaller, piercing, obliquely, the 
 Predate Gland, and terminating in the under part of the Neck 
 of the Bladder. 
 
 The Orifices of thefe Canals are feparated from each other by 
 a Caruncula, or round Projection of the Membrane of the Ure- 
 thra, termed Veru montauum , — of, from being bioad behind and 
 voffriform before, it is compared to the Head and beak of the 
 Wood cock, and called Caput jallinaginis. 
 
 'Fire Veiiculae Seminales are commonly confidered as Refcrvoirs 
 of the Semen, receiving it from the Vafa Dcferentia, and after- 
 wards, — by a power inherent in themfelves, affifted by the aftisn 
 of the neighbouring Mul'cles, particularly of the Levatores Ani, 
 — propelling it to the Urethra. 
 
 The Semen is prevented from paffing into the Bladder, the 
 opening from it being (hut while that Fluid is expelled. 
 
 Various experiments have been made on the Veficula: Semi- 
 nales by the late Mu. Hunter, from which he was of opi- 
 nion, that they are not Refervoirs of Semen, but Glands, fe- 
 creting a particular Mucus ; — that, with oilier parts, they are 
 fubfervient to the purpol'es of Generation and that the Bulb of 
 the Urethra is the receptacle of the Semen in which it is ac- 
 cumulated previous to its ejeffion. 
 
 The Profiate Gland, named from its fituation before the Vefi- 
 culaea Sem nales, lies mimediately behind the under end of the 
 Symphyfis of ihe Pubis, and reds upon the Inteltinum Reftum. 
 
 It furrounds and clofely embiaces the Neck of .the Bladder, or 
 beginning of theUretlua; but the greater part of it is placed 
 pofteriorly and laterally, having a Lobe projefting on each fide. 
 
1 28 
 
 It i s about the'fiz'e'of a Walnut, and of the figure of a Spanifii 
 Chefiuit,— or it refetnblesa Heart as commonly painted on Play- 
 ing-cards, with the Bafe towards the Bladder, and the Point 
 towards the Penis. 
 
 It has a Spongy Subdmce, but is one of the firmed Glands of 
 the B v ody, and generally fends out ten or twelve Duds, which 
 open obliquely at the ’beginning of the Urethra, at the fides ol 
 the Caput Galbnagtn's, and neat the teimination of the Seminal 
 Du£fs. 
 
 From the Dufls of the Proflate Gland, a thin white Liquor 
 is diicharged,— b om th fame caufes, and at the fame time with 
 the Semen, — into the Uiethra, and is fuppofed to b j ufeful in 
 the procefs of Generation ; — or, according to fome Authors, 
 this Fluid facilitates the paflage of the Semen through the 
 Urethra. 
 
 The Blood -veffels, Abforbents, and Nerves of the Veficulas 
 Seminales and Prodate Giand, ate in common with thofe of the 
 parts which furround them. 
 
 P E N I S. 
 
 The Penis , which has obtained a variety of other names, 
 fuch as Merfibrutn Virile , Meutula , Sec. confilis of three S .ongy 
 Subdances, two of which form the upper pait and fid s, or Body 
 of the Penis and are tetmed Corpora Caver noj'a Penis, the 
 third lunounds the Urethra, and has the name of Corpus Spon- 
 giofum Urethras. 
 
 The Penis is covered with a continuation of the common inte- 
 gument's, which are thinner than eii'ewhere, and, indead of Fat, 
 there is as in the Scrotum, a Reticular Subdance only under the 
 Skin. 
 
 At the anterior extremity of the Penis, the Integuments foim 
 a loofe fold, te'rned >' repuce, which is connected to- the .-inter. or 
 and- under pat t, or Glaus of the Penis, by a triangular fold, 
 called Pr.enum Preputii. 
 
 The t.orpora Cavernofa Penis refemble two equal but irregular 
 Cylinders, clofely applied to the i.des of each other, and each 
 covered by a droira, eitdtic, Ligamentous Sheath, the Fibres ot 
 which run in a tranfveife, and pattly in an oblique direftion. 
 
 They ar-ife one on each fide, by two bitr.J Conical extremities, 
 calhd their Crura, from the inner part ot the Crura of tire Ofla 
 Ifchta and Offa Pubis, to both of which they are very firmly 
 connefled by Ligamentous Snbi-ances. 
 
 At tire under part of the S . mphyfis of the Pubis, they are uni- 
 ted to each' other, and continue fo till they teach the Glands, 
 where the) ten bifnate in a.i;o bided exit entity; 
 
 At the; upper mart of i lie root u uhe .Pen's, the L'n amcntoiis 
 Sheath of the Corpora Cavernoia fends up a Proeels ol a triungu- 
 
129 
 
 lar form, to be connected to the Syrnphyfis of the Ofla Pubis, 
 under the name of Ligamentum Sufpenforium, by which the Body 
 of the Penis is fup ported, and prevented from prefling too much 
 upon the Scrotum. 
 
 The Corpora Cavernofa leave a Groove above, for the princi- 
 pal Vein of the Penis, and a Channel below for the Cavernous 
 Subilance of the Urethra. 
 
 The internal fubltance of the Corpora Cavernofa ccnfifts of 
 loofe reticular Plates, foinewhat Gmilar to the Cancelli in the ends 
 of long Bones, and, like them, readily communicating with 
 each other. 
 
 Upon the Cells of the Corpora Cavernofa,- the Arteries are plen- 
 tifully difperfed, and open freely into them, the Blood of the 
 Arteries tinging the Cells in the relaxed date of the Penis, and 
 filling them completely when it is difltended. 
 
 The Corpora Cavernofa are united to each other by a Septum 
 or Partition, formed by a continuation of the Elaitic Ligament 
 which covers thefe Bodies. 
 
 The Septum Penis is compofed of Cords, extending, nearly in 
 a parallel direction, from the Dorfum, or upper part of the Penis, 
 to the Corpus Spongioi'um Urethrae. 
 
 Between the different Cords, FiJJ'ures are left, through which 
 the Blood, or an inje.fted Fluid, palfes without obftruftion from 
 one of the Corpora Cavernofa to the other. 
 
 The Corpus Spongiofum Urethrae is fituated under and between 
 the Corpora Cavernofa Penis, but projefts confiderably beyond 
 them. 
 
 It begins a little behind the part where the Corpora Cavernolu 
 are united, adheres to them by condenfed Cellular Subltance, and 
 terminates at the anterior extremity of the Penis. 
 
 It has an external covering fimilar to that of the Corpora Ca- 
 vemofa Penis, but more delicate and more of a Membranous ap- 
 pearance. 
 
 The pofterior part of the Corpus Spongiofum is dilated into 
 a longitudinal Prominence, of a Conical form, fituated within the 
 Skin of the Perineum, and termed Bulb of the Urethra. It ex- 
 tends from the root of the Penis to near the Anu~, projefts mod 
 towards the under and back pu t, and is divided anteriorly by a 
 .Septum. 
 
 The Corpus Spongiofum is continued along the under part of 
 the Coi pora Cavernofa, and at the end of thefe expands into the 
 Sublhmce called Gians Penis, which covers and indoles the ends 
 of the Corpora Cavernofa. 
 
 The Gians or Nut, named from its refemblance to an Acorn, 
 is feparated from the Corpora Cavernofa by a continuation of the 
 Ligamentous Sheath which covers them, and is encircled at its 
 pofterior part by a prominent margin, called Corona Glandis, be- 
 hind which is a Cervix or Neck. 
 
130 
 
 The Surface of the Gians is covered with a Plexus, chiefly of 
 Venous Veffels, and with Nervous Papilla ?, which give it its l'en- 
 fibility ; and thel'e are incloi'ed in a fine Membrane continued 
 from the infide of the Prepuce. 
 
 About the Cervix and Corona of the Gians, are many Follicles, 
 termed Glandules Odorij'tree, which di fell urge a Sebaceous Mat- 
 ter, to preferve the fenflbility of the Gians, and allow the Pi e- 
 puce to move backwards and forwards upon it with facility. 
 
 The Internal Stru&uie of the Bulb of the Urethra and Gians 
 of the Penis, is of the fame nature with that of the Corpora 
 Cavernofa ; and the Internal Strufture of the reft of the Corpus 
 Spongiolum differs from that of the Corpora Cavernofa only in 
 this, that the Ceils are fmaller and of a more delicate texture. — 
 Some Anatoinifts confider the greater part of the Corpus Spon- 
 giofum as merely a Plexus of convoluted Veins. 
 
 The Urethra, named from the Uiine paflinj through it, is a 
 long Canal, the Diameter of which is nearly equal to that of a 
 writing-pen. It begins at the under and fore-part of the Bladder, 
 runs through the Corpus Spongiolum, and terminates in the 
 point of the Penis by a longitudinal Orifice. 
 
 At its origin, it defeends a little, and then paffes forwards, 
 under the Symphyfis of the OfiTa Pubis, to which it is clofely 
 connefted by Cellular Subftance : It then afeends at the under 
 and fore-part of the Offa Pubis, varying in the remainder of its 
 courfe, according to the different degrees of relaxation ordiften- 
 lion of the Cells of the Penis. 
 
 There are commonly three Dilatations in the Urethra ; one of 
 which is at the Proftate Gland, the fecond in the Bulb of the 
 Urethra, and the third about the beginning of the Gians. 
 
 In general, it has alfo the fame number of J. light Contraptions ; 
 the firtt at its origin from the Bladder, the fecond between the 
 point of the Proftate Gland and Bulb of the Urethra, and the 
 third at the point of the Gians. 
 
 Between the point of the Proftate Gland and part where the 
 Urethra pene’. rates the Corpus Spongiofum,— including nearly the 
 fpace of a Finger’s -bi eaarh, — i he Urinary paff.,ge is entirely Mem- 
 branous, and covered only with the common Cellular Subftance. 
 
 At the upper fide of the Bulb, the Urethra enteis the Corpus 
 Spongiolum, m which it i incloled to its termination in the point 
 of the Penif. 
 
 The infide of the Urethra is lined by a very Vafcular and fenfi- 
 ble Membrane, wh.ch is obferved to poffefs a certain degree of 
 contradf il ity, and is therefoie prefumed by leveral Anatom ills 
 to be endowed with Mufculnr F bres. 
 
 Between the Corpus Spongiofum and Membrane which lines 
 the Urethra, el'pecially towards the Septum of the Penis, nume- 
 rous Lacunae of different fizes are fi uated, one or two ot which 
 in particular, next the Glands, are often confiderably larger that) 
 the left. 
 
131 
 
 They run in a longitudinal direction from behind forward, and 
 perforate the Urethra bv Orifices large enough to admit a Brittle. 
 — They dif'cha.ge a bland Mucus for the defence of the Uie- 
 thra. 
 
 Belides the Lacunae, two fmall bodies, each about the fize of 
 a Garden-pea, 3re frequently met with, and are termed, from 
 their difeoverer, Covvper’s Glands. 
 
 They are fituatcd at the fides of the Membranous part of the 
 Urethra, — between its Bulb and the point of the Prolfate Gland, 
 — and covered by the Accelerator Mufcles. 
 
 When prefent they are o' ferved to d fcharge from their Dufls 
 into the Urethra, a Fluid which is liippofed to ferve the fame 
 purpofe with that of the Lacunae. 
 
 The Arteries of the Penis are chiefly from the Pudicae Com- 
 munes, which are Branches of the Internal Iliacs, and partly 
 from the Femoral Arteries. 
 
 Each of the Pudic Arteries having paffed out of the Pelvis, 
 through the great Notch of the Os ilium, runs between the 
 Sacro-Sciatic Ligaments to the inner fide of the Tuber Ifchii, 
 from which it paffes along the Crus of that Bone, and of the Os 
 Pubis, to the root of the Penis. 
 
 In its coutfe, it funufhes Branches to the adjacent parts, and 
 afterwards gives off three principal Branches, which belong to 
 the Penis : — One of thefe goes to the Bulb of the Uiethra, to be 
 difperfed in the Corpus Spongiofum ; — the other two, which are 
 larger than the former, go to the Body of the Penis, one of them 
 penetrating its Crus, and running' in the centre of the Corpus 
 Cavernofum ; the other paffing between the Symphyfis Pubis and 
 joining of the Crura Penis, and extending along the Dorftim as 
 tar as the Corona Glandis. 
 
 The Branches of the Femoral Artery to the Penis communi- 
 cate with thofe of the former, and are chiefly difperfed upon the 
 Integuments. 
 
 The Arteries of the Penis are divided into minute Ramifica- 
 tions, which communicate with each other, and with their fellows 
 on the oppoiite fide and terminate partly in the correfponcling 
 Veins, and partly in the Cells of the Penis. 
 
 The Veins arife, fome from the extremities of the Arteries, and 
 others by large open Mouths from the Cells of the Penis. 
 
 The greater number of the Veins unite into a Trunk, called 
 Vena Magna Penis, which runs in the fuperior Groove formed by 
 the union of the Corpora Cavernofa, and is furniflied with Valves, 
 and with thick Alton g Coats. 
 
 The Vena Magna, at the under end of the Symphyfis Pubis, 
 feparates into Right and Left Plexus, which pafs to the corre- 
 fponding Iliac Veins. 
 
 To an oblfrudf on of the courfe of the Blood through the 
 Veins, by the pte fibre of the Mufcles at the root of the Penis, 
 
 ;> "f . 
 
132 
 
 together with an increafed influx-through the Ai'terids, is owing 
 that accumulation ot Blood in the Corpora Cavernofa, which 
 occafions a diltenfion of the Penis. 
 
 The relaxation of the Penis happens from the caufes which 
 produced the dlftenfion being removed ; — The Elaftic Ligamen- 
 tous Membrane which covers the Penis again forcing the Blood 
 from the Cells into the Veins. 
 
 Upon the Surface of the Penis, there are fmall Superficial 
 Veins, which communicaie with thofe deeper feated, and com- 
 monly terminate by one or more Branches in the Veins at the 
 top of the Thighs 
 
 Thefe Branches affift in carrying on the circulation, and return 
 part of the Blood during the diftenfion of the Penis. 
 
 Of the Lymphatics of the Penis, thofe from the Prepuce and 
 Skin., in genera], go to the right and left Inguinal Glands, while 
 the Lymphatics from the Gians and ’Body of the Penis accom- 
 pany the Arteries into the under part of the Pelvis. 
 
 The Nerves of the Penis are large in proportion to the fize of 
 thdt Organ. They come from the Hypogaffric Plexus, and prin- 
 cipally from the laft Sacral Nerves, and are diftributed chiefly up- 
 on the Ligamentous Sheath which inclofes the Corpora Cavernofa. 
 
 They are fituated upon the Doifum of the Penis, more laterally 
 than the Arteries which lie between them and the principal Vein. 
 
 For the Mufcles of the Penis, fee Part IT. 
 
 The Penis ejeJls the Semen into the Vagina, and ferves for the 
 conveyance of the Urine from the Bladder. 
 
 ■oooooooo-csoooooooo 
 
 OF THE 
 
 ORGANS OF URINE AND GENERATION 
 
 IN THE FEMALE. 
 
 The Kidneys, Renal Glands, and Ureters, have the fame fitu- 
 ation and llrufl'ure as in the Male. 
 
 The Bladder has alfo the fame fituation behind the Ofla Pubis, 
 but rifes higher when it is in the diftended (late. 
 
 It is propoi tionally larger than the Bladder of the Male, and 
 is broader from one fide to the other,, corretponding to that part 
 of the Cavity of the Pelvis to which it belongs. 
 
133 
 
 The Urethra is much fhorter, — being fcarcely two inches in 
 length, — and ftraighter than in the Male, having only a flight 
 bend downwards between its extremities. 
 
 It is produced from the mod depending part of the Bladder, 
 has no proftate Gland, but is furnilhed, as in the Male, with 
 Lacurue , which open into it, and difcharge a Mucus to defend 
 it from the Urine. 
 
 The Parts of Generation in the Female (which are here fup- 
 pofed to be in the unimpregnated Hate) are divided into Internal 
 and External. The former confift of the Uterus and its Appen- 
 dages, the latter are thofe which are feen without any Difledlion. 
 
 Internal Parts. 
 
 The Uterus , Matrix, or Womb, is a hollow Vifcus, lituated 
 in the Peivis, in the Hypogaftric Region, between the Bladder 
 and Reftum, with which it is connected. 
 
 It is of a triangular figure, and a little flattened before and be- 
 hind, but more fo anteriorly ; is large above, fmall below, and 
 has two angles at its upper and lateral parts, called Corners of 
 the Uterus. 
 
 It is diftinguilhed into Fundus, or tipper part, which includes 
 the fpace above the infection of the Fallopian Tubes, the Body 
 -or middle, and Cer-uix or under part, the two laft being nearly 
 of equal length. 
 
 The extent and figure of the Uterus varies confiderably in dif- 
 ferent fubjedts.— In Women who have never been pregnant, it is 
 commonly about two inches and a half in length, from one inch 
 and a half to two inches in breadth at the Fundus, and about 
 half as broad at the Cervix. — It is near an inch in thicknefs, and 
 is la'ger in Women who have borne Children, thanin the Virgin 
 ftate. 
 
 The Cavity, like the external part of the Uterus, is of a tri- 
 angular jorm, but is fmall in proportion to the fize of the Organ, 
 —being fcarcely capable of containing the Kernel of an Almond, 
 — and has its fides clofely applied to each other. 
 
 It is covered externally through its whole length, with a fmooth 
 polifhtd Coat, continued from the Peritoneum, which, at the 
 under part of the Cervix, is refledled forwards upon the Bladder, 
 backwards over the Redtum, and laterally towards the Sides of 
 the Pelvis. 
 
 Its Subftance is- of a compadl, Cellular, and Flelhy nature, 
 and plentifully fupplied with Blood-velfels : The Flelhy Fibres, 
 however, are feen diftindlly only in the Gravid Uterus. 
 
 It is remarkably Vafcular in its Body, lefs fo in its Cervix, and 
 is nearly of the fame thicknefs throughout, excepting at its Cor- 
 ners, where the Uterine or Fallopian Tubes terminate. 
 
 Vol. II. M 
 
 
134 
 
 It is lined with a fine and very vafcular Membrane, of a fome- 
 what Porous and Villous appearance, in which the Arteries ter- 
 minate which difcharge the Menftrual Fluid. 
 
 The Cavity of the Cervix has two fmall Longitudinal Lines 
 projefting in it, one in the anterior, the other in the pofferior 
 part, on each fide of which are numerous Ruga. 
 
 The Ruga run, in an obliquely tranfverfe direflion, and arc 
 formed not only of the inner Membrane, but alfo by the Fibres 
 which compofe the Body of the Uterus. 
 
 Between the Rugae are many fmall Follicles, which difcharge a 
 Mucus for lubricating the parts near which they are placed 
 Some of them, being of a roundifh form, were mi (taken by Na- 
 both for Female Ovula, 
 
 The under part of the Cervix projects into the Vagina, fome- 
 what in form of the Gians Penis, and is perforated by a tranf- 
 verfe (lit, termed Os Tinea: , from its fuppofed refemblance to the 
 Mouth of the Tench Fifli. 
 
 The Os Tinea, in an Uterus which has never been impreg- 
 nated, is about the fize of the orifice of the Urethra in the Male, 
 but nearly twice as laige in the Uterus of a Woman who has 
 borne Children. 
 
 Itisfmooth on its external fnrface, is placed obliquely in a di- 
 ^reftion towards the back-part of the Vagina, and is (unrounded 
 with feveral Mucous Follicles. 
 
 Appendages of the Uterus. 
 
 The Appendages of the Uterus, are the Broad and Round Liga- 
 ments, the Onjaria, the Fallopian Tubes, and the Vagina. 
 
 The Ligamenta Lata, termed fometimes Ala Vefpertilionis, 
 from their refemblance to the Wings of a Bat, are two Membra- 
 nous produ&ions, or Doublings of the Peritoneum, fent from the 
 edges ot the. Uterus and pofterior extremity of the Vagina, to be 
 fixed to the fides of the Pelvis. 
 
 Along with the Uterus, they feparate the Pelvis into anterior 
 and pofterior Cavities, and are themfelves divided into large and 
 fmali, or anterior and pofterior Alse or Pinions. 
 
 They contain and fupport the Ovaria and Uterine Tubes, with 
 part of the Spermatic and Uterine Vefi’els and Nerves. They 
 likewifir inclofe a portion of the Ligamenta Rotunda, &c. con- 
 ned! the Uterus to the fides of the Pelvis, and affift in retaining it 
 in its place. In the time of Geftation they become effaced, by 
 furniftiing the Uterus with part of its external covering. 
 
 The Ligamenta Rotunda are two long and (lender Cords, ccm- 
 pofed of Veflels and Ligamentous Fibres, arifing from the Cor- 
 ners of the Uterus, immediately before and below the Fallopian 
 Tubes, from which they defeend obliquely in the Ligamenta 
 Lata, diminishing a little in their courfe towards the Groins. 
 
135 
 
 They pais through the Rings of the Abdominal Mufcles, in 
 the fame manuer as the Spermatic Cords do in the Male, and are 
 afterwards inferted by feparate Branches into the upper and late- 
 ral parts of the Pudendum. 
 
 They affift the Ligamenta Lata in preferving the equilibrium 
 of the Uterus. 
 
 The 0*varia, anciently called Tefies Muliebres, are fituated at 
 the tides of the Fundus of the Uterus, about an inch diftant 
 from it, and are contained in the pofterior Pinions of the Liga- 
 menta Lata, which form a Coat to them fimilar to the Tunica Al- 
 buginea Tellis. 
 
 The Ovaria are plain above, and prominent and femi oval be- 
 low, flattened at their anterior and pofterior Surfaces, and the 
 ftze of each, when in a ftate of the grealelt maturity, nearly equal 
 to half of the Male Tellicle. 
 
 They are large, uniform, and fm'both, in the vigour of life, but 
 become finall, unequal, and (hrivelled, in Old Women, or in thofe 
 who have borne many Children. 
 
 They are attached to the Uterus by the Ligamenta Lata, and 
 by two fmall Cords, termed Ligamenta Rotunda Ovarii, which 
 were miltaken by the Ancients for Vafa Deferentia, carrying a 
 fecreted Liquor to the Uterus. 
 
 They ate compofed internally of a loofc whitifli Cellular Sub- 
 ftance, intermixed with Vefiels and Nerves, and contain a num- 
 ber of fmall Veficles, called Ova, filled with a limpid Fluid, 
 which partakes of the qualities of the White of an Egg. 
 
 Thefe Veficles differ much in fize in the fame Ovarium 
 largefl of them are feldom equal to the fize of a fmall Garden- 
 pea. 
 
 The number of Ova is differently eftimated by different Ana- 
 tomifts, — from ten to twenty and upwards having been found in 
 one Ovarium. 
 
 According to experiments made by Mr. Hunter, it is afcer- 
 tained, — that the number of originally exifting Ova in each Ova- 
 rium, whether that number be greater or fmaller, may be dimi- 
 nifhed, but cannot be increafed. 
 
 The Ovana ferve for the nomifhment of the Ova, which con- 
 tain the rudiments of the Foetus. 
 
 The Uterine, or Fallopian Tubes, compared in fhape, by Fal- 
 lopius, to that of a Trumpet, are two Conical and Vermiform 
 Canals, attached to the Corners or the Uterus, and terminating 
 in it, each by a fmall Opening which fcarcely admits the entrance 
 of a Briftle. 
 
 They become gradually larger in them pafi'age towards the fides 
 of the Pelvis : Near their outer extremity, they are convoluted 
 and coniiderably dilated, but are afterwards fuddenly contrafled, 
 and terminate by open Months fufficiently large to admit the point 
 et a Goofe-quil). r 
 
136 
 
 Their outer ends are free and fluctuating in the Pelvis, and ex- 
 pand into many irregular jagged or pointed extremities, called 
 i'imbria, which are conliderably longer at one fide of the Tube 
 than the other. 
 
 They are commonly upwards of a hand-breadth in length, 
 and contained in a Doubling of the Ligamenta Lata.— In their 
 natural filiation, they lie near the Ovaria ; but when drawn out 
 and extended, are a Finger's-breadth diftant from them. 
 
 The itruCture of the Tubes is nearly the fame with that of the 
 Uteius, and, like it, they are capable of dilatation and contraction : 
 Their Inner fide, however, has a different appearance, being fur- 
 nifhed with many (mall longitudinal Plicae, which are moll con- 
 Ipicuous towards the outer extremities. 
 
 The Tubes are fuppofed to convey the prolific part of the Male 
 Semen from the Uterus to the Ovaria, in order to foecundate the 
 Ova ; and by grafping that part of the Ovarium where the ripeft 
 Ovum is fituated, to carry the Ovum, according to fome Au- 
 hors, or its contents only according to others, to be mixed 
 with the Male Semen, and to be lodged in the Cavity of the 
 Uterus. 
 
 The Vagina is a Membranous Canal, which extends from the 
 Neck of the Uterus to the opening of the Pudendum. 
 
 It is fituated behind the Bladder and Urethra, ar.d before the 
 under part of the Inteftinum ReCtum, to each of which it is clofely 
 connected by Cellular Subftance. 
 
 It begins a little above the Internal Orifice of the Uterus, but 
 reaches higher at the pofterior than anterior part ; from which 
 circumftance, together with a flight Curvature it has backwards, 
 the Canal is found to be longer in its pofterior than anterior 
 Surface. 
 
 From the Os Tine as, it paffes downwards and forwards, and 
 terminates between the Labia Pudendi, the Axis of the Vagina 
 forming a confide) able Angle with that of the Uterus. 
 
 The dimenfions of the Vagina correfpond with the fize of the 
 Penis in the Male ; but vaiy according to the temperament if 
 the Body, and become larger in Women who have borne Chil- 
 dren. 
 
 The Body of the Vagina is compofed of thick, ftrong, Mem- 
 branous parts, and furnifhed internally with numerous irregular 
 Rug# or Wrinkles, ar.d Nervous Papilla, the former of which 
 confiderably diminifh the capacity of the Canal, and the latter add 
 to its fenfibility. 
 
 The Ruga run in a tranfverfe direction, and are fodifpofed as 
 to divide the Vagina into anterior and pofterior Columns, which 
 join together laterally, and produce a Raphe or Suture at the 
 right and left fides. 
 
 They aie deepeft, largeft, and moft crowded upon the anterior 
 and to winds the outer part of the Vagina; are moft confpicuous 
 
137 
 
 in Virgins, lefs fo in married Women, and become more and more 
 effaced in thole who have borne Children. — The Rugae facilitate 
 the diitenfion of the Vaginajluring Child-birth. 
 
 The whole extent of the Vagina, particularly towards its outer 
 extremity, isfuniifhed with linall Follicles, the orifices of which 
 can frequently be fein. 
 
 Tiiey fupply a Mucus, with which the Canal is always lubri- 
 cated, and which is difeharged, in time of Coition, in fuch abun- 
 dance, as to have been formerly confidered as an emilfion of Fe- 
 male Semen. 
 
 The outer end of the Vagina is covered, on effcfi fide, by a 
 Subftance compofed of Blood- velfels. and Cells fimiiarto thole of 
 the Penis, and defcribed by De Graaf under the name of Plex- 
 us Reteformis , and by later Anatomiits under that of Corpus Ga- 
 * vernof&m Fagind. 
 
 The Corpora Caasernofa are covered by the Sphinfter Vaginas 
 Mufcle, the aftion of which, joined to the Dilatation of thefe 
 Bodies, ferves to contrail the entry of the Vagina in the time of 
 Coition. 
 
 The Ufe of the Vagina is to receive the Penis and Semen, and 
 to convey from the tferus the Menltrual Flux, the Foetus, the 
 Secund.nes, and the Lochia. 
 
 The Uterus, with its Ligaments, Ovaria, and Uterine Tubes, 
 are fupplied with Blood from the Spermatic and Uterine Ar- 
 teries. 
 
 The Spermatic Arteries a ife from the Aorta, as in the Male, 
 and run in the Ligamenta Lata, to be difperfed upon the Ovaria 
 and Uterine Tubes, and afterwards upon the Uterus itlelf. 
 
 The Uterine Arteries are derived from the Internal lliacs, and 
 are much larger than the Spermatics. They direct their courl'e, 
 fil'd to the under part of the Uterus, after which they afeend along 
 its edges, and near its upper part join the Spermatic Arteries. 
 
 From the Uterine chiefly, and partly from the Spermatic Ar- 
 teries, many I'm ,11 Branches are furnilhed, which run in a Ter- 
 pentine manner, and communicate with their fellows in the oppo- 
 fite fides of the Uteius. 
 
 The Vagina is fupplied with an Artery on each fide. — termed 
 Paginal ., — from the Uterine, and with linall Branches from the 
 Umbilical, M ddle Htemorrhoidal, and Pudendas Communes. 
 
 The Spermatic Feins have the fame termination as in the Male, 
 but are coniiderably larger.— -The other Veins run into the Inter- 
 nal Iliac. 
 
 The Lymphatics, like the Blood-velfels, run alfc- in two Sets. 
 Thole of the one fet accompany the Spermatic Blood-vcflels, and, 
 like the Abforbents of the Telles in the Male, go to the Lumbar 
 Glands. Thole of the other correlpond with the Hypogaftric 
 Blood-velfels, and terminate in the Glands at the lateral parts of 
 the Pelvis. 
 
 Vol. [I. M 2 
 
133 
 
 Tile Nerves are from the Sacral and Great Sympathetics- 
 The Ufe of the Uterus is, — to receive from the Ovaria, by 
 means of the Fallopian Tubes, the Rudiments of the Foetus, — 
 to nourifh it, and, after bringing it to maturity, — to expel it 
 through the Os Internum Uteri and Vagina.— From the Inner 
 Surface of the Uterus, the Menftrual Evacuation is alfo dif. 
 charged. 
 
 The I ntern al Parts, called Pudendum or Vulva, are formed 
 of two prominent fides, termed Labia Pudendi, Labia Externa, 
 or Alee MTRbres. Thefe are contiguous, when the Limbs are 
 not much feparated, thereby preventing the accefs of Air to 
 the Internal Parts, which they at the fame time protect and con- 
 ceal. 
 
 The upper part of the Pudendum, named Pubes or Mous Ve- 
 neris, is fituated on the fore-fide of the Ofl'a Pubis, and is cover- 
 ed with Hair fimilar to that in the Male, and beginning to grow 
 about the fame period of life. 
 
 The Pubes is compofed of the Common Integuments, under 
 which a confiderable quantity of Fat is fituated, rendering it 
 thick, foft, and prominent. 
 
 The Labia Pudendi extend from the Pubes to within about an 
 inch of the Anus, the fpace between the Pudendum and Anus 
 obtaining the name of Perineum, from a moifture fuppofed to 
 flow about this part of the Skin. — It is fomerimes alfo called An- 
 terior Perineum, to diftinguifh it from that part which extends 
 from the Anus to the Coccyx, termed by feme Anatomifts Po- 
 Jlerior Perineum. 
 
 The opening between the two Labia has the name of PoJJ'a 
 Magna ; — it increafes a little in fize and depth as it defeends, and 
 forms a fmall boat-like Cavity at its under extremity, termed 
 FoJJ'a Navicularis. 
 
 The Labia are thickeft above, become thinner below, and ter- 
 minate in a tranfverfe fold of the Skin, named Franum , Furcula , 
 or Fourcbette, which is frequently lacerated in the fii ft Child- 
 birth. 
 
 The Labia are cotnpefed of the Skin elevated by a large quan- 
 tity of Cellular Subftance and fome Fat, and lined by a very 
 Vafcular Membrane, which is thin, tender, and red like the in- 
 flde of the Lips, and is furnifhed with numerous Sebaceous Fol- 
 licles, fecreting a Liquor, whereby the parts are preferved frnooth 
 and moift. 
 
 Between the upper ends of the Labia, is the Subftance named 
 Clitoris, and by fome Mentula Muliebris, — not exceeding an inch 
 in length, and little more than the third part of that in thicknefs, 
 and tied down to the fore-part of the Symphyfis Pubis. 
 
 External Parts. 
 
139 
 
 It is extiemely Vafcular and Nervous, and is compofed, like 
 the Penis in the Male, of two Crura and Corpora Cavernofa, 
 contained in a Ligamentous Sheath, with a Septum between 
 them. 
 
 The Crura are upwards of twice the length of the Body of the 
 Clitoris, and, together with Mufcles belonging to them, arife, as 
 the Crura of the Penis do in the Male, from the Crura of the Offa 
 Ifchia and Pubis. 
 
 The Clitoris is alfo provided with a Ligamentum Sufpenforium, 
 by which it is conneCled to the Ofla Pubis, and with a Gians , 
 which, like that of the Penis, is extremely fenfible* but has no 
 perforation in it for the paflage of the Urine. 
 
 It is covered by a continuation of the Skin of the Labia, which 
 at its inferior extiemity, forms a Semilunar Fold, termed Prepu- 
 tiurn Clitoridis. 
 
 The Prepuce is furnifhed with Glandula Odorifera upon its 
 inner Surface, and with a final! Frsenum which fixes it to the 
 Gians. 
 
 In the time of Coition, the Gians Clitoridis is fuppofed to pro- 
 duce nearly the fame fenfation in the Female, as the Gians Penis 
 does in the Male. 
 
 At the under and outer part of the Clitoris are two Bodies, 
 called Nymph re, from their being fuppofed to prefide over and di- 
 reCt the courfe of the Water proceeding from the Bladder. 
 
 The Nympho: arife narrow from the Prepuce and Gians, and 
 run obliquely downwards and outwards along the infide of the 
 Labia, increafing in breadth, but fuddenly contracting again at 
 their lower extremity. 
 
 They are chiefly formed by a production of the infide of the 
 Labia, have the fame florid colour with them, and in their natu- 
 ral ftate are contiguous, and cover the Orifice of the Urethra. 
 
 They are fometimes of unequal fize, and not unfrequently, 
 particularly in warm climates, they projeCi beyond the edges of 
 the Labia. 
 
 Their Internal Structure coniifts of Cellular Subllance, with 
 a large proportion of Blood- veflels. They have alfo many Ner- 
 vous Papillae, which render them very fenfible, and Sebaceous 
 Follicles, the contents of which prevent them from being injured 
 by the Urine. 
 
 The Nymphse aflift in directing the courfe of the Urine from 
 the Urethra, and in preventing the Air from entering the Vagina. 
 — They alfo tend to enlarge thePaffage for the Child in the time 
 of Parturition. 
 
 Between the Perineum and Nymphae, there is afmooth Cavity 
 or VeJUbulum, which is molt complete in Virgins, and leads to 
 two Paflages, viz. to the Urethra above, and to the Vagina be- 
 low. 
 
HO 
 
 The Orifice of the Urethra is placed a little below the Gians 
 of the Clitoris, and between the two Nymphae, and is furiound- 
 ed by a Spongy Eminence, which proje&s at its under part, — 
 called by fome Authors Corpus Glandulofum, or Glandule P re- 
 flate? Mulierum. 
 
 The Corpus Glandulofum is perforated by Lacunee, fome of 
 •which are of conliderable depth, and difeharge a Vifcid Matter 
 round the Orifice of the Urethra. 
 
 The Orifice of the Vagina termed likewife Os Externum Uteri, 
 is placed immediately under that of the Urethra, and is natural- 
 ly (traitef^Than the reft of the Canal, but in the Virgin (fate is 
 ftill more con trafled by the Subftance called Hymen, or C irculus 
 Membranofus, which partly furrounds it. 
 
 The Hymen approaches to a Circular Figure, but the Circle is 
 frequently incomplete next the orifice of the Urethra, the broad 
 part being turned towards the Perineum. 
 
 When the Hymen is ruptured, it degenerates into fmall Coni- 
 cal Papillse, termed Carunculte Myrtiformes, from their fuppofed 
 refemblance to Myrtle berries. 
 
 The Hymen has been confidered as a Teft of Virginity ; — 
 but neither the prefence nor abfence of this Membrane can be 
 depended upon as a certain Criterion. 
 
 About the Orifice of the Vagina are feveral Mucous Follicles, 
 fimilar to thofe round the Opening of the Urethra. 
 
 The Blood-veffels and Nerves of the External Parts are from 
 the Pudic Branches, and are difperfed in numerous Ramificati- 
 ons upon the end of the Vagina, Labia Externa, and Clitoris. 
 
 The Abfqrbents pafs partly to the Inguinal Glands, and partly 
 to thofe placed at the fides of the Pelvis, or upon the Lumbar 
 Vertebrae. 
 
 . 00000000 -» 00000000 ' 
 
 OF TIIE GRAVID UTERUS. 
 
 When the Rudiments of the Foetus have been conveyed from 
 one of the Ovaria into the Cavity of the Uterus, through the 
 medium of the correfponding Uterine Tube, whether in the ftate 
 of a Fluid only, or of a complete Ovum, Impregnation is faid to 
 have taken place. 
 
141 
 
 Some days after Impregnation has commenced, an Ovum, con- 
 fiding of a Veficle filled with a limpid Fluid, is found in the Ca- 
 vity of the Uterus. 
 
 The Ovurn, when firft vifible, is obferved to have a fmooth 
 Surface, but in a (hort time thereafter it fends off flocculent 
 Branches, the greater part of which are by degrees converted in- 
 to a Placenta at that part of the Uterus where the Ovum happens 
 to be firft attached. 
 
 The Rudiments of the Foetus, however, are not always 
 conveyed to the Uterus after Impregnation, for fometiines a Foe- 
 tus is found in the Ovarium ; at other times in one of the Uterine 
 Tubes j and fome rare Inftances have occurred, where the Em- 
 bryo has dropped from one of the Ovaria or Tubes, into the Ca- 
 vity of the Abdomen, where a Placenta has been formed, by 
 which it has been nouriftied. 
 
 The Ovum, at an early period of Geftation, confifts of a thin 
 Membranous Capfule, which inclofes the Embryo or Germ with 
 the Umbilical Cord and Waters ; and the Capfule, again, con- 
 fifts of an internal Membrane called Annios, on the outfide of 
 which is the ’True Chorion, which is covered with a Filamentous 
 and Spongy Subftance, termed by Ruysch Tunica Filamentofa, 
 and by more modern Authors, Falfe or Spongy Chorion. 
 
 The Spongy Chorion is defcribed by Dr. Hunter as confid- 
 ing, in early Geftation, of tnsjo Layers, one lining the Cavity of 
 the Uterus, and termed by him Membrana Decidua, from being 
 fuppofed to be call off from the Uterus : The other, covering 
 that part of the Ovum which does not adhere to the Uterus, he 
 terms Decidua Reflex a. 
 
 The Decidua is lead diftimff between the Uterus and Placenta. 
 Near the edge of the Placenta, both it and that part of it called 
 Reflexa, are thickeftand ftrongeft, and decreafe in thicknefs tow- 
 ards the other end of the Uterus and Ovum, in proportion as 
 thefe become more expanded. 
 
 The Decidua and Decidua Reflexa unite into one Membrane 
 in advanced Geftation. They have been fuppofed to be formed 
 originally by an effloi efcence thrown out upon the parts on v/hic^h 
 they are placed, in the manner it is thrown out upon inflamed 
 l'urfaces. 
 
 Between the Amnios and Chorion, a Gelatinous Fluid is con- 
 tained in the early Months, at which period a final 1 Bag, filled 
 with a milky-l’ke Fluid, is obferved on the Amnios, near the 
 Umbilical Cord, and is termed Peflcnla Umbilicalis or Alba. 
 
 T'ne Veficula Umbilicalis is conceited to the Cord by a Fila- 
 ment confiding of an artery and Vein; which, w'th the Fluid and 
 Bag, foon difappear. The life of this Veficle, which has fome- 
 tiines been miftaken for an Allantois, is not yet ur.derftood. 
 
 In early Geftation, the Ovum is large in proportion to the 
 Embryo ; but towards the latter period of Pregnancy, the propor- 
 tion is reverfed, as appears from the following Obfervations. 
 
 ■ . Sg|jfe; ft -sMM.. j . 
 
142 
 
 No well authenticated account has been yet received, of the 
 Embryo being obfervable till near the end of the third Week* 
 when it is found to appear like an oblong Veficle floating in the 
 limped Liquor of the Ovum. 
 
 In the fourth Week, the Ovum is about the fize of a Pigeon’s 
 Egg, and the Embryo not larger than that of a common Fly. 
 
 About tire end of the third Month, the Ovum is the iize of a 
 Goofe’s Egg, and weighs eight ounces, while the Embryo is be- 
 tween two and three ounces in weight, and three inches in length ; 
 —and the Head and Extremities being now diftincliy obfervable, 
 it obtains the name of Faitus, which it retains from this time till 
 the end of Geftation. 
 
 In the fixth Month the Placenta and Membranes weigh feven or 
 eight ounces, the Foetus, twelve or thiiteen, and is tighter nine 
 Inches in length, and perfect in all its external parts. 
 
 At Birth, the Seeundines weigh only between one and two 
 pounds, the Foetus lix or feven, and is from eighteen to twenty- 
 two inches in length. 
 
 Still however, from the difficulty of ascertaining when Preg- 
 nancy commences,— from the differences of Foetufesof the fame 
 age in different Women, and in the fame Woman in different 
 Pregnancies, and — from the Foetus being. -frequently retained in 
 the Uterus fome time after it is dead, as well as from the fmall 
 dependance to be placed upon many of the Figures given of 
 thefe Parts, — the above Obfervations are not altogether to be de- 
 pended upon. 
 
 Changes Produced in the Uterine System by 
 
 Immediate! y after Impregnaffon, a large Orifice is conftantly 
 obferved in the Ovarium, leading to a Cavity in that part of it 
 from whence the Rudiments of the Foetus have been derived. 
 
 This Cavity appears firft floeculent, and is afterwards filled up 
 with a Granulous Subftance, which has the name of Corpus Lu- 
 teum , from the yellow appearance it affumes, efpecially in 
 Quadrupeds. 
 
 The Corpus Luteum , confifts of an outer Vafcular, and an in- 
 ner Inorganic-looking Subftance, which has been confidered by 
 fome Authors as the remains of the Ovum. 
 
 The Corpus Luteum is not found till after Impregnation. It 
 contines during Pregnancy, and for fome time after Delivery, 
 when it gradually vanifhes, hut leaves a Scar in the Ovarium, 
 which continues for life. — The number of Corpora Lutea cor- 
 refponds with that of the Ova impregnated. 
 
 After the Embryo is received into the Cavity of the Uterus, 
 the Os Tine* is (hut up by a Ropy Mucus fecreted from the Fol- 
 
 Impregnation. 
 
143 
 
 llcles in the Cervix Uteri ; the Menftrua ceafe to /«w, — and the 
 Uterus by degrees is changed from a triangular to an oval form. 
 
 From the influx of Blood, and the growth of the Ovum, the 
 Cavity of the Uterus gradually enlarges from a fize capable on- 
 ly of admitting an Almond, to that which contains the full- 
 grown Foetus, the Secundines and Waters ; compofing together 
 a Mafs equal to nine or ten pounds weight. 
 
 Some time after impregnation, the Fundus and Body of the 
 Uterus, being fofter and loofer than the Cervix, firft yield to the 
 parts which it contains. 
 
 For the two firft Months, the Uterus increafes fo little as to 
 remain in the Cavity of the Pelvis, and it is generally after the 
 third month, before the Tumour formed by it can be felt above 
 the Symphyfis of the Pubis. 
 
 During the firft three Months, the Os Tineas remains fmooth 
 and even, and its Orifice is nearly as in the v,n--.ir.pregn;ited 
 ftate ; but between the third and fifth Month, the Cervix and 
 Orifice begin to be dilated, the former becoming fofter, and the 
 latter changing its common appearance, and projeiling more into 
 the Cavity of the Vagina. 
 
 The Uterus continues to rife through the whole period of Gef- 
 talion, but frequently inclines a little- to one fide. — In the l’eventh 
 Month, it reaches the Umbilicus, and at laft touches the Scro- 
 biculus Cordis, Stomach and Colon, occupying rhe whole of 
 the Umbilical Epigaftric Regions. 
 
 In the progrel's of Geftation, the whole Uterus becomes fofter, 
 loofer, and more Vafcular, and the Veflels are greatly enlarged, 
 the proportional increafe being nearly fimilar to that of the Ute- 
 rus. 
 
 The courfe of the Arteries is remarkably convoluted, — fully 
 as much fo as they are previous to Conception, — and greatly more 
 fo than that of the correfponding Veins. 
 
 The Veins are much larger than the Arteries, their diameters 
 being fuch as to have diftinguifhed thereby the name of Sinufes j 
 —and to them the great bulk of the Uterus is chiefly owing. 
 
 The fubftance of the Uterus was formerly fuppofed by fome to 
 be thicker, and by others to be thinner in the Gravid, than in the 
 unimpregnated ftate ; but the generality of Anatomifts feem now 
 fufficiently fatisfied, that it is nearly of the fame thicknefs in 
 both (fates, and during t fie whole term of Pregnancy. 
 
 In the latter Monthsj the Tubercle of the Os Uteri is confi- 
 derably enlarged, and the firmnefs of its texture converted to 
 tne Spongy foftnefs of the Body of the Uterus. The tranfverfe 
 Rinia or Orifice is changed into an oval Pit, and in Women who 
 have borne feveral children, it is confiderably dilated near the end 
 of Geftation. 
 
 The fituation of the Appendages of the Uterus is alfo confide- 
 rably altered. The Ovaria, with the Tubes and Ligaments of 
 
the Uterus, are lower fituated, in refpe£l to the Fundus Uteri, 
 in proportion as it afcends ; and at the full time, the Broad Li- 
 gaments, by afliffing in forming a covering to the Uterus, are 
 nearly obliterated. 
 
 In the enlarged (late of the Uterus, the Mufcular Fibres are 
 diftinctly feen. — They form Fafciculi which run in various di- 
 rections, but cannot be traced far without interruption. 
 
 A defcription is given by Ruysch of a Circular Mufcle in the 
 bottom of the Uterus, for the expulfion of the Placenta ; — but 
 the Placenta is found to adhere to other parts befides the Fundus 
 Uteri; nor has fuch a Mufcle been obferved by later Anato- 
 mifts. 
 
 The Mufcular Fibres of the Uterus aflift in the delivery of the 
 Child and expulfion of the Placenta ; and in a few days after- 
 wards, the Uterus, partly by the contraCtile power of thefe Fi- 
 bres, and partly by that of the Blood-veffels, is reftored to near 
 its former dimenfions. 
 
 Contents of the Uterus about the end of 
 Pregnancy. 
 
 The Contents of the Uterus, towards the end of Pregnancy, 
 con lift of the Foetus, the Umbilical Cord Placenta, Membranes, 
 and Waters. 
 
 The Cord, Placenta, and Membranes, are named the Secun- 
 dines, or After-birth, with which fome include the Waters though 
 thefe are difcharged previous to the expulfion of the Child. 
 
 The Cord is fixed by one end to the Umbilicus of the Foetus, 
 and by the other it is attached to the Placenta at a little diftanee 
 from its middle, from which circumftance the extra&ion of the 
 Placenta is more eafily effeCled. 
 
 It is commonly about two feet long, — in fome instances moje, 
 in others lefs ; but in general it is of fufficient length to allow the 
 Birth of the Child, while the Placenta adheres to the Uterus of 
 the Mother. 
 
 Its thicknefs is nearly equal to that of ones Finger, but fmal- 
 ler and weaker at the extremity next the Placenta. — It is feldom 
 of a cylindrical form, being marked with Sulci correfponding to 
 the courfe of its Veffels. 
 
 It is compofed of one Vein and two Arteries, which twift about 
 each other in a fpiral direction, and are covered by a fmooth Coat 
 derived from the Membranes. 
 
 The Trunks of the Veffels are inclofed in a Gelatinous Cellular 
 Subfance, which adds to the (Length and elalficity of the Cord, 
 and allows the Blood to pafs freely between the Foetus and Pla- 
 centa, without being in danger of interruption from preffure. 
 
145 
 
 The Vein is much larger than the Arteries ; it is deftitute of 
 Valves, and fends off no Branches till it reaches the Foetus. 
 
 It arifes from the fubftance of the Placenta, and, after perfo- 
 rating the Umbilicus, it paffes in the inferior part of the Liga- 
 mentum Sufpenforium, to the under fide of the Liver. 
 
 The Arteries arifefrom the Iliac Arteries of the Foetus, per- 
 forate the Umbilicus, and run to the Placenta, in the fubftance 
 of which they divide into their ultimate Branches, vifriere the 
 Ramifications of one Artery frequently form large Anaftomofes 
 with thofe of the other, and both communicate with the Branches 
 of the Vein, in the manner Arteries and Veins do in other parts 
 of the Body. 
 
 The Ufe of the Cord is, by means of the Vein, to convey pure 
 Blood from the Placenta for the nourilhment of the Foetus, and, 
 through the medium of the Arteries, to return what is not ufed 
 in Nutrition, again to be mixed with the Blood of the Uterus.— 
 By the intervention of the Cord alfo, the Placenta is more readi- 
 ly extrafled. 
 
 The Placenta fo called from its refemblance to a broad Cake, 
 is a fpongy mafs, of a round form, occupying near a fourth part 
 of the Ovum. 
 
 It is about feven or eight inches in breadth, and upwards of 
 one inch in thicknefs, but is thinner at the edges where the Mem- 
 branes go off. 
 
 The external futface, or that next the Uterus, is divided into 
 Lobules with deep FifTures, while the internal, or that next the 
 Foetus, forms a regular Mafs, which has numerous large Branch- 
 es of the Umbilical Veffels difperfed upon it. 
 
 In the Placenta are to be oblerved, — on the fide next the Child, 
 the ramifications of the Umbilical Veffels forming the principal 
 part of its fubftance, — on the fide next the Mother, Branches of 
 the Uterine Arteries, almoft of the fize of Crow-quills, palfin^ 
 in a convoluted manner between the U Writs and Placenta, and 
 terminating in the latter ; — Veins correlponding with thefe Ar- 
 teries but flat and of great fize, running obliquely to the Ute- 
 rus, — and, in the fubftance of the Placenta, an Appearance 
 which has been fuppofed by many Authors to be the common 
 Cellular Membrane, of a tender nature, and eafily ruptured by 
 injection, but which is confidered by late Authors as a regular 
 Spongy Subftance, fimilar to that in the Body of the Penisf 
 
 The Placenta is connefted to the Uterus on one fide, by Blood- 
 veffels and by the Decidua, and to the Foetus on the other bv 
 means of the Umbilical Cord. ’ i 
 
 The common place of attachment is near the Fundus Uteri 
 though it is found at different times adhering to all the other parts 
 of the Uterus, not even the Os Tincse excepted. ^ 
 
 In the cafe of Twins, there is fometimes only one, but raoft 
 frequently two diltindl Placentae, adhering together br the in- 
 VOL. II. N 
 
146 
 
 tervention of a Membrane in which the Veflels of the two Pla- 
 centa: occafionally communicate with each other. 
 
 There are in thefe cafes alfo, two diftinff Apartments feparated 
 by a Partition, each Apartment containing its own Waters and 
 Cord. 
 
 The Ufe of the Placenta is, to receive Blood from the Uterus, 
 and, according to the opinion of modern Anatomifts, to purify 
 it, (as the Lungs do in the Adult), for the nourifliment of the 
 Foetus. 
 
 The Membranes confift of the Spongy Chorion, the True Chorion , 
 and the Amnios. 
 
 They form a complete but (lender Bag, which lines the Ca- 
 vity of the Uterus, and inclofes the Foetus, Umbilical Cord, and 
 Waters. 
 
 The Spongy Chorion is a thick opaque fubftance, which adheres 
 to the Uterus, and forms the outer Layer of the Ovum, but fcarce- 
 Jy penetrates between the Lobules of the Placenta. 
 
 Between the Uterus and Placenta, it is lefs d i ft i n 61 than elfe- 
 where, being perforated there, and in fome degree concealed by 
 the Blood -veflels proceeding from the inhdeof the Uterus. 
 
 It has a Spongy and Villous appearance, and is full of fmall 
 Blood-vefl'els,. which can be readily injefted from thofe of the 
 Uterus. 
 
 The True Chorion , — the term derived from Chorus'p Company, 
 numerous Veflels being found to exifl: in it in the Qua'fruped,-— 
 is thinner, fmoother, and much denfer than the former. 
 
 It is connected with the Spongy Chorion as far as the edge of 
 the Placenta, where it fepai ates from it, is reflefted over the Sur- 
 face of the PI '.centa, which is oppofed to the Foetus, and is af- 
 terwards continued over the whole of the Cord. 
 
 It is uniform in its texture, has a tranfparent appearance, ad- 
 heres to the Spongy Chorion and furface of the Placenta, by a de- 
 licate Cellular Subftance, and has no Veflels vifible to the naked 
 Lye, or which can be in*e<Sted. 
 
 The Amnios , — fo called, according to fome Authors, from its 
 fuppofed ; efemblance to a Veflel ufed by the Ancients for the re- 
 ception of Blood in Sacrifice, — lines the Surface of the True Cho- 
 rion, and, with it, is refle&ed from the Placenta upon the Cord, 
 which it fupplies with an external covering. 
 
 It is thinner, more denfc, and tranfparent, than the Chorion, 
 to which it adheres every where by a Jeliy. 
 
 It is fmooth and polifhed on the fide next the Foetus, and is 
 ■deftitute of Blood- veflels. 
 
 The Membranes, bei’des containing the Child and Waters, 
 give origin to the latter, and, in the time of Labour, aflift in open- 
 ing the Orifice of the Uterus. 
 
 "The Waters, called Liqour Amnii, are thinned: and cleared in 
 the fir ft Months, after which they acquire fome degree of colour 
 and ropinefs. 
 
147 
 
 The Liquor Amnii is chiefly compofed of the Serum of the 
 Blood. In its natural Hate, it has all the Charafters of the Li- 
 quor Pericardii, or of the Liquors exhaled from the Surfaces of 
 other Membranes fimilar to the Pericardium. — It is fuppofed to 
 be d erived from the Exhalent Arteries of the Amnios. 
 
 It is proportionally greater in quantity in the firft than in the 
 laft Months, but the proportion and quantity' vary confiderably 
 in different Women, and in the fame Woman in different Preg- 
 nancies. 
 
 Between the Amnios and Chorion, Water is frequently coi- 
 le£led, but in much fmaller quantity than in the Amnios, and is 
 termed Falfe Water, or Falfe Deli-very . — It is frequently ail- 
 charged forae time previous to the Birth of the Child, without any 
 danger. 
 
 The Liquor Amnii defends the Child and Umbilical Veffels 
 from the preffure.of the Uterus, afliits in di {lending the Uterus 
 duiing Geffation, and allows the Foetus a certain degree of mo- 
 tion. 
 
 In the time of Labour, it alfb aflifts iu dilating the Mouth of 
 the Uterus, and, by lubricating the Vagina, facilitates Delivery . 
 
 Peculiarities of the Fcetus. 
 
 All the Bones of the Body, excepting a few, are fojt, yield- 
 ing, and imperfect , and many of them entirely in a fate of Car- 
 tilage. . 
 
 File Head is large in proportion to the reft of the Body, and the 
 Bones of the Cranium are united by Membrane, which allows the 
 nze of the Head to be diminiflied, whereby its Paffage is facilita- 
 ted in the time of Delivery. 
 
 Between the Frontal and Parietal Bones, is the Membrane 
 called Bregma, formed by the Dura Mater and Pericranium, 
 which commonly difappears before the Child is two years of age, 
 the margins of the Bones being then united, 
 
 —The other peculiarities of the Bones o f the Foetus are taker, no- 
 tice of in the Defer iftion of the Bones of the Adult . — 
 
 There is a large proportion of Fluids, and the Solids are gene- 
 rally /o//er than in the Adult. 
 
 The Skin is of a bright red colour, in confequence of its greater 
 degree of Vafcularity. 
 
 That part chiefly of the Cellular Membrane is Adijnfe, which 
 is upon the Surface of the Body ; fcarcely any Fat being found 
 in the interior parts, where it gradually accumulates as the per- 
 fon grows older. 
 
 The Brain, Spinal Marrov/, and Nervous Syftem, are propor- 
 tionally larger, but fofter. 
 
 The Sanguiferous Syftem, and Glandular Organs, are larger. 
 
 In the Eye is the Metnbrana Pupillaris, which arifes from the 
 nner margin of the Iris, and completely covers the Pupil. 
 
143 
 
 It leparates the Camerae from each other, and is very Vafcular, 
 According to Blumenbach, itkeeps the Iris expanded, during 
 the rapid increafe of the Ball of the Eye. 
 
 The Cryftalline Lens is almoft Spherical, and has numerous 
 yeJJ'els difperied upon its Caplule. 
 
 The Meatus Auditorius is wholly Cartilaginous, and adheres 
 by its extremity to an impeifefl Bony Circle, in which the Mem 
 brana Tympani is placed. 
 
 The Meatus Extei nus, and Membrnna Tympani, are lined by 
 a Mucous Membrane, which is call off after Birth. 
 
 The Thymus Gland, in the Foetus, is a large Subftauce, fitu- 
 ated in the upper part of the Thorax, between the Layers of the 
 Anterior Mediaftinum. 
 
 It lies over the Pericardium, and occupies the fpace where the 
 Aorta fends off the Carotid and Subclavian Blanches, and ex- 
 tends a fhort way into the fore-part of the Neck. 
 
 It has tvuo long Cornua above, and t-zuo broad Lobes below, 
 is of a pale-red colour, and becomes afterwards of a darker hue. 
 
 A nvhile ferous liquor can frequently be fqueezed from its fub- 
 flance ; but it has no Excretory Duff ; nor is the ufe of the Fluid, 
 or of the Gland itfelf, yet afeertained. 
 
 Some Anatomifts are of opinion, that the white Fluid is Chyle 
 fent by a retrogade motion from the Thoracic Du£l, and that the 
 Thymus Gland is a Diverticulum to the Chyle, when too great 
 a quantity of Lymph is fent to the Subclavian Vein. 
 
 In the Adult, the Thymus Gland is fo completely abfoi bed, 
 that fcarcely any thing but Cellular Subftance remains in its 
 place. 
 
 The Blood-veffels of the Thymus are Branches of the Sub- 
 clavian and Internal Mammary ; the Nerves come from the Great 
 Sympathetics and Eighth Pair. 
 
 Its Lymphatics have not yet been very accurately traced. 
 
 The Lungs are fmall, firm, and of a dark-red Colour, and Jink 
 when thrown into water, in confequence of the Bronchial Cells 
 having not yet received A : r. 
 
 But if Air be admitted to them by putrefaffion or otherwife, 
 they fiwim in Water, in the fame manner as if Air had been cen- 
 veyed to them in confequence of Refpiration. 
 
 The Valve of Euftachius is difnnSl in the Fcetus, but frequent- 
 ly Cribriform in the Adult, is larger in proportion, and is fup- 
 pofed to direft the Blood of th^ Inferior Cava, immediately 
 through the Foramen Ovale to tiucLeft Auricle. 
 
 In the back-part of the Septufn, between the Right and Left 
 Auricles, is the Foramen Ovale, nearly equal in fize to the 
 Mouth of the Inferior Cava, bounded by a thick Mufcular edge, 
 termed Annulus Foraminis Ovalis. 
 
 Upon the left fide of the Foramen Ovale, a Membranous Valve 
 is placed, which allows part of the Blood of the Right Auricle 
 
149 
 
 to pafs through the Foramen Ovale immediately to the left one, 
 but which completely prevents its return. 
 
 The Blood going through the Foramen Ovale, afbfts in keep- 
 ing up the balance of Circulation between the two fides ot the 
 Heart, till the Lungs be ready to receive it. 
 
 ThePulmonary Artery divides into three Branches, the right 
 and left of which run to the Lungs, while the middle one, called 
 Dufius Arteriofus , larger than both the other Branches, and its 
 Area nearly equal to that of the Foramen Ovale, pafles in an ob- 
 lique direction to the beginning of the defcending Aorta. 
 
 The Dufius, or Canalis Arteriofus, forms nearly one half of 
 the Aorta, carries part of the Blood of the Right Ventricle into 
 that Artery, without allowing it to pafs to the Lungs ; and the 
 Aorta, formed in this manner, receives thefo ce of both Ventri- 
 cles, by which it is more enabled to fend Blood through the Um- 
 bilical Arteries to the Placenta. 
 
 The Stomach is of a rounder form than in the Adult, and com- 
 monly contains a fmall quantity of a Gelatinous Matter. 
 
 The Appendix Vermiformis is larger in proportion, and is in- 
 ftrted into the extremity ©f the Colon, which - , at this time, does 
 not projefl to foim a. proper Cxcum. 
 
 The Colon, and fiequently all'o the end of the Ilium, are 
 filled with a greenijh black Faces, of a vifcid coqiiftence, termed 
 Miconium . 
 
 The Liver is fo large as to occupy both Hypochondriac Re- 
 gions. 
 
 The Umbilical Fein pafles from the Umbilicus, in a duplicature 
 ot the Peritoneum, to the left Branch of the Vena Portae, and 
 carries the Blood from the Placenta to the Liver. 
 
 From the Trunk of the Umbilical Vein, where it terminates in 
 the Liver, a Branch, called DuFlus, or Canalis Venofus, runs in a 
 iomewbat waving direflion, and joins the Left Vena Hepatica, 
 where that Vein enters the Cava. 
 
 The Dufius Venofus is much fmaller than the Trunk of the 
 Umbilical Vein, and carries part of the Blood of the Vein direfl- 
 ly to the Heart, without allowing it to enter the Circulation in 
 the Liver. 
 
 The Umbilical Vein fends Branches to the Right Lobe of tli« 
 Liver, but is principally diftributed through the Left Lobe; 
 while the Right Branch of the Vena Ponte carries the Blood 
 of the Splenic and Mel'enteric Arteries to the Right Lobe of the 
 Liver. 
 
 After Birth, the Left Lobe of the Liver, which was formerly 
 more particularly fupplied by the Umbilical Vein, receives an ad- 
 ditional proportion of Blood from the Vena Portarum. 
 
 The reafon why the Umbilical Vein goes partly to the Cava, 
 and not entirely to the Heart, is not underftood. 
 
 Vol. II. In 2 
 
150 
 
 The Kidneys are irregular on their Suiface, being formed of 
 Lobes, each of which confilts of a Cortical, a Medullary part, and 
 a Papilla, and is covered by a Proper Membrane. 
 
 1 he Giandula Renalis is almolt as large as the Kidney, but af- 
 terwards rather diminifhes than increafes in fize. 
 
 The Bladder of Urine is of a long form, and extends almoft 
 to the Umbilicus. The greater part of it is above the Pelvis, and is 
 more particularly covered by the Peritoneum than in the Adult. 
 
 1 he Urachus, which is of a Conical form, alcends from the 
 bottom of the Bladder, between the Umbilical Arteries, and be- 
 tween the Peritoneum and Linea Alba, to the Umbilicus, and 
 vaniihes by degrees in the Umbilical Cord. 
 
 It is formed by a production of the Fundus Veficae, and in 
 the Human Body is generally folid, forming a Sufpenfory Liga- 
 ment of the Bladder. 
 
 It has been fometimes found hollow at its beginning and 
 has been laid to be fo, in one or two inftances, throughout its 
 whole length. 
 
 In the Foetal Quadruped, it is a large Tube, which tranfmits 
 Urine from the Bladder to a Bag between the Amnios and 
 Choi ion, called Allantois. 
 
 The common Iliac Arteries divide, on each fide, into a fmall 
 External, and large Internal Branch. 
 
 The principal part of the Internal Iliac is occupied in forming 
 the Umbilical Arteries, which mount by the (ides of the Bladder, 
 on the outfide of the Peritoneum, and perforate the Umbilicus 
 in their progrefs to the Umbilical Cord. 
 
 Soon after Delivery, the Foramen Ovale, Dutus Arteriofus, 
 and Venofus, with the Umbilical Vein and Arteries, begin to 
 contrail, and are, in general, completely clofed, and the Veflels 
 fhri veiled into Ligaments within a year after Birth. 
 
 This obliteration is produced by a contractile power in the parts, 
 by a preflure in the l'urrounding Vifcera, and by the Blood being 
 direted through other channels. 
 
 The Pelvis of the Fcetus is commonly fo fmall, that the prin- 
 cipal parts of its Vifcera are contained in the open cavity of the 
 Abdomen. 
 
 The Prepuce of the Clitoris is proportionally fo much larger in 
 a young Fcetus than it is afterwards, that, in an Abortion, a Fe- 
 male Foetus has been frequently miflaken for a Male. 
 
 The Teltes are lodged during the greater pa; t of Geftation, in 
 the Cavity of the Abdomen, over the Pfoas Mufcles, and a lit- 
 tle below the Kidneys. 
 
 They then conflitutea part of the Abdominal Vifcera, and, in 
 a fimilar manner with them, are connected to the Body by a pro- 
 duction of the Peritoneum, which forms their Tunica Albu- 
 ginea. 
 
151 
 
 Between the Tefticle and Scrotum, a Fibrous and Vafcular 
 Subftance, of a conical form, is extended, — called by Mr. 
 Hunter, Gubernaculum, or Ligamentum Tejris, which he con - 
 fiders as a principal agent in directing the courle of the Tefticle, 
 and in making way for it in its defcent. 
 
 About the eighth month of Pregnancy, the Teftis, by means 
 not yet completely afcertained, pafles gradually along to the 
 Scrotum, a Procefs of the Peritoneum preceding it, which af- 
 terwards forms its Vaginal Coat. 
 
 The Teltis through the whole of its courfe, continues to be 
 cohered by the Peritoneum, is connected to the parts on which it 
 reds, and has its Vefiels palling to it from behind forwards, the 
 fame as when fituated in the Abdomen. 
 
 While the tefticle is palling through the Ring of the Abdomi- 
 nal Mufcle, the Ligamentum Teftis is found to be in fome mea- 
 i'ure inverted, and to form the under and fore-part of the Vaginal 
 Coat, on which the Cremafter Mufcle is expanded. 
 
 After the defcent of the Tefticle, the Peritoneal Procefs, which 
 defcends along with it, begins to contrail at the Ring, and a firm 
 adhefion of its fides, to within a little diftance of the Tefticle, 
 is commonly found to he produced by the time of Birth. 
 
 In the firft Months, the Embryo fwims in the L’quor Amnii, 
 free from the prelfure of the furrounding parts and from many 
 diffisitions and obfervations made by the lateft Anatomifts, it is 
 afcertained, — that the Head preponderates, and in general con- 
 tinues undermoft till the Child is delivered. 
 
 Formerly it was fappofed that the Embryo, in the firft Months, 
 was fituated with the Head uppermoft, and that, in the latter 
 Months, the attitude of the Foetus was inverted. 
 
 The Foetus is obferved to be coiled up into as round a figure 
 as polfible, fo as to be properly adapted to the Cavity of the 
 Uterus. 
 
 The Head is bent towards the Thorax, and the arms are folded : 
 — The Knees are drawn towards the Abdomen, and the Heels 
 towards the Nates. 
 
 The Spine s bent into an Arch, and one fide of the B .dy of 
 the Foetus i : frequently turned forwards. 
 
 The Head is placed diagonally, with its long Diameter corre- 
 fponding to that of the Pelvis, and the Occiput oppofed to the 
 Os Tincae. 
 
 Circulation of the Blood in the FoeTUs. 
 
 The Blood is ftnt by the ArteAesof theUteius to the Sub- 
 ftance of the Placenta, from which accord ng to moft of the 
 ancient An.it ,- fts, p aflr.s to the Umhibcal Vein by a di- 
 refl -.om.v.u .in of B'fnches; or, acco ding to the opinion 
 of the greate . n or modern Anatomifts, — by Abforbtion. 
 
 Position of the Fostus. 
 
152 
 
 ' By the Umbilical Vein it goes principally to be circulated in 
 the Liver, and by the Du£lus Venofus, a fmall portion of it 
 goes to the right Auricle of the Heart. 
 
 The Blood fent from the Inferior Cava is tranfmitted by the 
 Foramen Ovale to the left Auricle, and that fent by the Superior 
 Cava is tranfmitted to the right Auricle and Ventricle, and from 
 thence to the Pulmonary Artery. 
 
 From the Pulmonary Artery, one portion of it paffes through 
 the Circulation of the Lungs, and another goes by the Duc- 
 tus Arteriofus to the Aoita Defcendens. 
 
 From the Lungs it is returned by the Pulmonary Veins to the 
 Left Auricle, where it mixes with that coming from the right 
 Auricle by the Foramen Ovale, and is fent by the Aorta to the 
 different parts of the Body. 
 
 From the Iliac Arteries, it is conveyed by the Umbilical 
 Branches to the Subftance of the Placenta, where one portion of 
 it returns by correfponding Veins to the Foetus, the reft going 
 to the Uterus in the manner it was difeharged from the Uterine 
 Arteries to the Branches of the Umbilical Vein. 
 
1.53 
 
 PART V. 
 
 OF THE 
 
 ABSORBENT STSTEM. 
 
 Of the Absorbents in General. 
 
 T HE Abforbent Syflem confifts of the Ahforhent Veffels and 
 Conglobate Glands, the former of which are divided into Lym- 
 phatic and Lafteal Vefj'els. 
 
 The Abforbents are fmall pellucid Tubes, which have been dif- 
 covered in moll parts of the Body, and are fuppofed to exift in 
 all. 
 
 They begin by numberlefs open Mouths, too minute to be via- 
 ble to the naked Eye; though, by the afTiftance of Glades, the 
 Orilices of the La£Ieals have been feen in the Human Body by 
 Mr, Cruickshank, and thole of the Lymphatics, in certain 
 k nds of Fillies, by Dr. Monro. — See their Treatifes upon ibis 
 Subjell. 
 
 They arife from the external Surface of the Body, from the 
 Cellular Subrtance, from the Surfaces of the large Cavities, and 
 from the Surface and Subfiance of the different Vil'cera; — but 
 have not yet been obferved in the Cavity of the Cranium, or in 
 the Placenta and its Membranes. 
 
 In the dfferent parts of the body in general they run in two 
 fets, one fuperficial and very numerous, the ether accompanying 
 the Arteries, and at leaft double their number. 
 
 The Lafteals are of the lame nature with the other Abforbents. 
 They begin from the infide of the Intertines, and, when thel’e 
 conain Alimentary matter, they carry a white Fiuid, called 
 Chyle, and at other time;, a Clear Fluid or Lymph, to be mixed with 
 the contents of the Lymphatics, 
 
15-4 
 
 Moft of the Lymphatics, and all the La&eals, terminate in 
 the Thoracic Duff, by which the Lymph and Chyle are conveyed 
 to the Red Veins, to be mixed with the Blood. 
 
 The common place of termination is in the large Veins in the 
 bottom of the Neck ; — no Fadls or obfervations having been yet 
 eftablifhed of their terminating in any other part of the Venous 
 Syftem. 
 
 The Coats of the Abforbents are thinner and more tranfparent, 
 but ftronger than thofe of the Red Veins, being able to fupport 
 a Column of Mercury of confiderable weight ; but from their 
 thinnefs they cannot be enumerated. 
 
 They are generally fuppofed however to be formed of different 
 Membranous Layers, like the Blood-veffels. Fibres can be feen 
 in them, and their Mufculaiity is rendered probable by the Con- 
 traftile power which they are obferved to poflefs in a living or 
 moribund Animal. 
 
 By this conti ability they convey their contents from their Ori- 
 gins towards their terminations, in which they areaflifted by the 
 motions of the 1'urrounding parts, independent of fuch a Vis a 
 tergo as contributes to propel the Blood through the Veins. 
 
 They are furnifhed with Blood-vejfels for their nourifhment, as 
 is fcmetimes obferved by penetrating injections ; and this is ren- 
 dered (fill, more evident by their being fufceptible of inflamma- 
 tion and pain. 
 
 Theprefence of Ner-ves ., alfo appears probable from the acute- 
 nefs of their feeling when in a (fate of inflammation. 
 
 In general, they form an irregular Net-work, having frequent 
 communications with each other ; and thefe are moft- numerous 
 in the vicinity of their Glands. 
 
 Through their whole extent, they are intercepted by Valves, 
 which are placed in pairs, and are of a femicircular form, having 
 one edge of each Valve fixed to the fide of the Vefl'el, and the 
 other edge loofe acrofs its cavity, but turned towards the general 
 terminations. 
 
 The Valves are found, in fome parts, to be fituated at equal 
 diftances ; in others, more irregularly. — Their number alio is 
 very uncertain, amounting in fome parts to three or four, and 
 in others to feven or eight, or upwards, in the length of an inch ; 
 — but varying ftill more with refpeCl to number, in different 
 Bodies, and in different parts of the fame Body. 
 
 When the Abforbents are diftended, they appear largeft on the 
 fide of the Valves towards their general termination, and the en- 
 largements are fuch as to give the Lymphatics a jointed, and the 
 Lafteais frequently a veficular appearance. 
 
 In the termination of the Abforbents, whether in the Thora- 
 cic DuCt, or in the Red Veins, there is always one and common- 
 ly two Valves, to prevent the contents of the Du£t or of the 
 Veins from palling into them. 
 
155 
 
 The Ufe of the Valves is to promote the general courfe ol the 
 Lymph and Chyle, and to prevent the retrograde motion of thefe 
 Fluids within their VefTels. 
 
 Ufe of the Abforbents : The Lymphatics take in the Fluids ap- 
 plied to their Orifices by Capillary A' traftion, and by a power 
 inherent in themfelves, and by their contrailile nature condufl 
 them into the Mafs of Blood, whereby they pievent morbid ac- 
 cumulations. — The LaHeals, in like manner, receive the Chyle 
 from the Inteftines for the nourifhment of the Boay. 
 
 The Conglobate Glands, or Glar.ds of the Abforbent VefTels, 
 are found in various parts of the Body, and are fi tutted in the 
 Cellular Subftance under the Skin, or over the Trunks of the 
 Blood-veffels belonging to the different Vifcera They are of a 
 round or oval form, and frequently a little flattened. 
 
 They are of different fizes, from that of a Millet-feed to that 
 of a Subftance near an inch in diameter ; and fometimes feveral 
 are collefted into one mafs. 
 
 Their colour alfo varies in different parts of the Body, and at 
 different times of life. 
 
 In young fubjefts, they are generally Iargeft, and of a reddifh 
 or brown colour, but become fmaller and paler with increafing 
 age; and immediately under the Skin, they are redder and firmer 
 than within the large Cavities. 
 
 They have a fmooth, denfe, Membranous Covering, which 
 gives them a fhining appearance, and are conneffted to the fur- 
 rounding parts by loofe Cellular Subftance. 
 
 Their Coat is connected to the Glandular part by a Cellular 
 Membrane, which, according to Dr. Haller, is pervaded by 
 a Succus proprius full of Globules, which, Mr. HEWSON fup- 
 pofed, afterwards form the Red Globules of the Blood. 
 
 L:ke other Glands, they have Arteries, Veins, and Nerves, 
 entering their compofition. 
 
 They are deferibed by fome Anatomifts, as being compofed of 
 Cells internally , while others confider them as being a Congeries 
 of convoluted Abforbent VefTels. — Moil of the Glands have much 
 of the former, but many of them of the latter appearance. 
 
 ; The Abforbents entering into the Glands, are called Vafa In- 
 ferentia. When they approach, or come in contact with the Gland, 
 they fplit into radiated Branches, which, after fpreading over it, 
 penetrate into its Subftance. 
 
 The greater part of the Abforbents, approaching a Gland, 
 terminate in it in this manner, while others turn alide, or °- 0 over 
 it, and terminate in other Abforbents or in other Glands. 3 
 
 From the oppofite fide of the Glands, VefTels go out in the man- 
 ner they entered if, and are termed Vafa Efferentxa. They are 
 frequently, though by no means always, fewer in number, but 
 larger than the Vafa Inferentia. 
 
 v Jjj - 
 
156 
 
 Mod of the Abforbents go through feveral Glands, but in fome 
 parts through one only, before they reach their general termina- 
 tions. 
 
 The Lymph and Chyle are drained through the Glands, by 
 which they are fpppofed to undergo certain changes,— but the na- 
 ture of thefe changes has not yet been afcertained. 
 
 Of the Particular Absorbents. 
 
 The Superficial Abforbents of the Lower Extremities, confift 
 of numerous Veffels, which lie between the Skin and Mufcles. 
 
 They belong to the Integuments in general, and are much more 
 numerous than the Subcutaneous Red Veins. 
 
 They can be traced from the Toes, round which they form a 
 Plexus. 
 
 From the Toes, feveral Branches, likewife forming a Plexus, 
 run over the top of the Foot, to the inner part of the Leg, and 
 from that along the correfpondmg part of the Knee. 
 
 From the outer part of the Foot, another Plexus arifes, which 
 runs along the outfide of the Leg, where it fplits into two Divi- 
 lions, one cf which erodes obliquely over the fore-part of the 
 Tibia, to the Lymphatics at the inner fide of the Knee. 
 
 The other Divifion paffes partly to the Popliteal Glands, fome 
 afeending upon the outer and back-part of the Thigh. 
 
 The Popliteal Glands are commonly two or three in number, 
 and are fituated near the Artery of the fame name, but frequent- 
 ly they are fo fmall and fo much buried in Fat, as to be difeover- 
 ed with difficulty. 
 
 From the Sole, another Plexus of Lymphatics arifes, and joins 
 thofe upon the Leg already deferibed. 
 
 From the i n fide of the Knee a Plexus runs up, confiding of 
 from twelve to twenty Trunks, which pals afterwards on the fore 
 and inner-part of the Thigh to the Groin. 
 
 The greater part of the Trunks of the 1 affc Plexus, accompa- 
 ny the Vein called Saphena Major, and in their pafTage they re- 
 ceive many fmall Branches from the outer and back-part of the 
 Thigh. 
 
 In the Groin, they fplit into Branches which penetrate the In- 
 guinal Glands. 
 
 The Inguinal Glands are generally from fix or eight to a dozen 
 in number, and are of very different fizes ; but fometirnes ihe 
 number is fmaller, in confequence of two or more of them being 
 united into one large Gland. 
 
 Of the Inguinal Glands, fome lie in the angle between the 
 Thigh and Abdomen, and others a few inches faither down on 
 the fore-part of the Thigh. 
 
 The greater number are placed upon the outer part of theTen- 
 dinous Aponeurofis, the red deeper, being in conta£> with the 
 great Blood-veffels. 
 
157 
 
 The fuperficial Lymphatics of the Thigh enter the lowed of thefe 
 Glands ; one or more of them, however, frequently pafs by the 
 full Glands they meet with, and penetrate others higher in the 
 Groin, and i’ometimes a few do not enter any Glands till they 
 go into the Abdomen. 
 
 Into the Inguinal Glands enter likewife the fuperficial Lym- 
 phatics of the upper and back-part of the Thigh, with thofe of 
 the Nates and of the Abdomen and Loins. 
 
 The deep -felted Lymphatics of the Lower Extremity are fitua- 
 ted among the Mufcles, — they accompany the Blood-vtffcls, and 
 are few in number when compared with the Subcutaneous fet. 
 
 In feveral places, one only has been yet obferved on each fide 
 of the Trunks of the Arteries, though, in others, they are 
 fomewhat more numerous, forming a Plexus over the Blood- 
 velfeis. 
 
 They arife from the fides of the Toes, and from the deep parts 
 of the Sole, accompanying the Plantar Arteries ; and after reach- 
 ing the Leg, they run up with the pofterior Tibial Artery to the 
 Ham. 
 
 In the Ham, they lie clofe upon the Trunk of the Artery, and 
 enter the Popliteal Glands. 
 
 Befides thefe, there are fimilarbut fmaller Lymphatics, which 
 begin upon the upper part of the Foot, and afterwards accom» 
 pany the anterior Tibial, and the Fibular Arteries, receiving 
 Branches from the deep parts of the fore and outer-fide of the 
 
 The anterior Tibial and the Fibular Lymphatics, terminate 
 with the pofterior Tibial in the Glands of the Ham. 
 
 From the Popliteal Glands, two and fometimes more Trunks 
 of confiderable fize are fent out, which accompany the Femoral 
 Artery, and, at different diftances, communicate with each other, 
 by Branches which pafs obliquely acrofs the Artery. 
 
 At the upper part of the Thigh, they enter the undermoft of 
 the Inguinal Glands, where the Lymph of the fuperficial and 
 deep-feated Abforbents of the Limb is mixed and incorporated. 
 
 The fuperficial Lymphatics of the Scrotum enter the upper and 
 inner Inguinal Glands, thofe deeper feated palTing with the Lym- 
 phatics of the Tefticle into the Abdomen. 
 
 The fuperficial Lymphatics of the Penis begin at the Prepuce, 
 and form a few Trunks which run principally upon the Dorfum 
 Penis, receiving in their paflage Branches which turn round from 
 its interior furface. 
 
 In fome Subjects, they unite into Trunks in the middle of the 
 Dorfum Penis, which afterwards feparate into right and left 
 parts. 
 
 In others, they are more unconnected, and in all they appear 
 to divide at the root of the Penis into right and left Branches, 
 
1-55 
 
 p-ailing into the correfponding Inguinal Glands, which lie next 
 the Symphyfis of the Pubis. 
 
 The deep-fated Lymphatics of the Penis arife from the Gians, 
 and from the Body of the Penis, and accompany the Arteries into 
 the under part of the Pelvis. 
 
 The Lymphatics of the Eefiicle are numerous, and are among 
 the largeft of the Body, fome of them exceeding the fize of a 
 Ciow-quill. 
 
 They arife from the Coats and Body of the Tefticle, and from 
 the Epididymis, and run with the Spermatic Cord through the 
 Ring of the Abdominal Mufcle, to terminate in the Lumbar 
 Glands. — In their paffage, they have few communications with 
 each other. 
 
 The Lymphatics of the External Parts oj Generation in Women, 
 go partly to the Inguinal Glands of each tide, and partly through 
 the Rings of the external oblique Mufclcs, in company with the 
 round Ligaments of the Uterus, and terminate in the Iliac or in 
 the Lumbar Glands. 
 
 The Superficial Lymphatics of the wider part of the Abdomen, 
 thole of the Loins, Nates, and verge of the Anus, pats into the In- 
 guinal Glands, each fet terminating in fuch of the Glands as lie 
 neared the parts to which the Vetfels belong. 
 
 The Inguinal Glands, having received the Lymphatics of the 
 Inferior Extremity, and likewife the Superficial Lymphatics of 
 the External Parts cf Generation, fend out Trunks fewer in 
 number, but confiderably larger than thole which entered the 
 Glands. 
 
 The Valla Efferentia of the Inguinal Glands enter the Abdo- 
 men under Pour art's Ligament, in company with the Inguinal 
 and Iliac Artery. 
 
 Some of them go into the Glands fituated about the Iliac or 
 the Lumbar blood-vcffsls. The Iliac Glands_ are frequently al- 
 anoft as numerous as the Glands of the Groin, and one of them 
 is generally found larger than the reft, and placed at the inner 
 ed"e of Poupart’s Ligament. The Lumbar Glands are more 
 numerous than any of the clafl'es already deferibed, and are placed 
 over the Abdominal Aorta, Inferior Cava, and bodies of the 
 Lumbar Vertebrae. 
 
 Tbe reft of the Lymphatics from the Lower Extremity de- 
 feend at the fide of the Pelvis, near the Internal Iliac Blocd- 
 veifels, and pals through fome of the Glands which are fituated 
 there. 
 
 The laft-mentioned Lymphatics are joined by Abforbents 
 from the vifeera of the Pelvis in general, efpecially by thofe of 
 the Bladder and Veficulse Seminales in the Male, and by a portion 
 of thofe of the Uterus and of the Vagina in the Female. 
 
 The Lymphatics oj the Bladder, in both fexes ; accompany its 
 principal Blood -veflels, pafs through fome fmill Glands upon 
 
159 
 
 the fide of it, and, at the under part of the Pelvis, go into the 
 Glands which furround the Internal Iliac Artery and Vetn.^ 
 
 The Lymphatics of the Uterus run in two Sets ; one, which Is 
 the larged, goes with the Hypogaltric, the other with the Sper- 
 matic Blood-veiTels. 
 
 The Hypogajlric Lymphatics form a Plexus which runs from 
 above downwards, into Glands fituated on the fides cf the V a- 
 gina. 
 
 From theie Glands they pafs to others which fur.und the In- 
 ternal Iliac Ve!lels,and then, intermixing with the Trunks from 
 the Extremities, they terminate in the Thoracic Du6t. 
 
 The Lymphatics, corresponding with the Spermatic Veflel^, 
 terminate in the Lumbar Glands, as in the Male. 
 
 The Lymphatics of the Uterus, like its Blood-vefTels, are 
 much enlarged and of confequence eafily difeovefed, in the Gra- 
 vid date. 
 
 The Lymphatics of the Rectum go firft into fmall Glands which 
 lie between it and the Os Sacrum, and afterwards terminate in the 
 Lumbar Plexus £>t Glands and Vefiels. 
 
 Befides the Lymphatics which lie on the infide of the Exter- 
 nal Iliac Artery, there are others fituated on the outfide of it, 
 upon the Ploas Mufele. 
 
 Of thefe, one part pafles up to the Lumbar Plexus, and goes 
 under the Aorta, in different Branches which terminate in the 
 Thoracic Duft. 
 
 Another part paffes under the Iliac Arteries, and appears upon 
 the Os Sacrum, forming a remarkable Plexus, which goes through 
 many Glands, and is chiefly fituated behind the Aorta and Vena 
 Cava. 
 
 The Lacteal Veffels , fo called from conveying a fluid like milk, 
 which is termed Chyle , begin upon the inner Surface cf the In- 
 teftines. Each Lafleal takes it origin upon one of the Villi, by 
 numerous fhort radiated Branches, and each Branch is furnifhed 
 with an Orifice for imbibing the Chyle. 
 
 From the Villi the Lafteals run a confiderable way under the 
 Mufcular Coat of the Intefrines, and then pafs obliquely through 
 them, uniting in their courfe into larger Branches. 
 
 They follow the direction of the Blocd-veflels, and their 
 Trunks are double the number of the Arteries, — one being fitu- 
 ated on each fide of them. 
 
 Upon the outfide of the Inteftines an External Set appears. 
 They run between the Peritoneal and mufcular Coats, and com- 
 monly proceed fomeway in the direftion of the Intelfine, and 
 with few ramifications. 
 
 d he Superficial and deep-feated Lafleals communicate in the 
 Subftance of the Inteffines, and, after leaving them, comm nly 
 form a Plexus, which runs between the plies of theMefentery and 
 Mefocolon, without following the courfe of the Blood-vefTels. 
 
 Jfa A 
 
ICO 
 
 The LaEleals of the Jejunum are larger and more numerous 
 than thofe of the Ilium , the principal part of the Chyle being 
 contained in this Inteftine. 
 
 In their cotirfe, they pafs through a great number of Lnfteai 
 or Mefenteric Glands, which like the La6teals themfelves, are 
 largett and molt numerous in that part of the Melentery which 
 belongs to the Jejunum. 
 
 T-Iit Mefenteric Glandsare feated in the Fat between the Layers 
 of the Mefentery, near the Branchings of the Blood-velfels. 
 
 They are commonly icattered over the Mefentery, a. a little 
 diltance from each other ; but there are feldom any obferved with- 
 in two or three inches of the Inteltines. 
 
 They are of different fizes in different parts of the Mefentery, 
 fome being about a half, or two thirds of an inch in diameter, 
 while others are fofmall as to be traced with difficulty. 
 
 Their Structure is the fame with that of the Abl'orbent Glands 
 in other parts of the Bodv, but they are generally flatter, and arc 
 of a white coLur when filled with the Chyle. 
 
 They are confidered by fome Authors as dividing the Laffeals 
 into different Orders. 
 
 From the Inteltines to the Glands, theLafteals are called Vaffa 
 Laclea Primi Generis , and from the Glands to the Thoracic 
 Duff, VaJJ'a Laclea Secundi Generis. 
 
 Somedivide them into three Orders ; — the firft confifting of thofe 
 which go from the Inteftines to the Glands,— the fecond, of thofe 
 which run from one fet of Glands to another,— and the third, 
 of thofe which pafs from the Glands to the Thoracic Du£t. 
 
 The I.afteals of the Small Intefines , after paffing through the 
 different Gians in the Mefentery, form at laft one, and freo,uent- 
 ly two, three j or more Trunks, which accompany the Trunk of 
 the fuperior Mefenteric Artery, till they arrive at the right fide 
 of the Aorta, where they fometimes pafs into the beginning of 
 the Thoracic Duft : At other times they defcend a little, and 
 join the Trunks from the Inferior Extremities, to form that 
 Dt)£l. 
 
 The Ahforbents of the Great are of an inferior fize in pro- 
 portion to thofe of the Small Jnteflines , and have feldom, though 
 fometimer, been obferved to be filled with Chyle. 
 
 In their .courfe they . o through the Mefocolic Glands, which 
 ate fituated between the Layers of the Mefocolon, but are gene- 
 rally much lefs numerous and confiderably fmnller than thofe of 
 the M' ic.'iery, or of moll other parts of the Body. 
 
 The Abforbents of the Caecum, and of the right faction of the 
 Colon join thofe of the final I lilteftines, about the root of the 
 Mefentery. 
 
 Thole of the left portion of the Colon accompany die Inferior 
 Mefenteric Arieiy, and, communicate with large Lymphatics 
 near its root. 
 
16 L 
 
 They terminate at laft in the Lumbar Glands, or go dire&ly 
 into the lower part of the Thoracic Du£L 
 
 Of the Abforbents of the Stomach, one fet runs upon its finally 
 and another upon its great Curvature, but neithe the one nor the 
 other are found to carry Chyle, though a few have been obferved 
 filled with it in other animals, — as the Dog. 
 
 The former of thefe, compofedof Branches fr m the upper and 
 under Surfaces of the Stomach, accompany the fuperior Co onary 
 Artery. 
 
 In their pafiage, they go through a few fmcll Glands fituated 
 at the junftion of the Omentum Minus to the Stomach, and, af- 
 ter becoming larger they enter other Glands in company witn the 
 deep-feated Lymphatics of the Liver, along with which they ter- 
 minate in the Thoracic Duel. 
 
 The other fet pafies from the great Curvature of the Stomach, 
 partly to the right, and partly to the left fide, and, as on the fmall 
 Curvature, are formed of Brandies from its oppofite Surfaces. 
 
 Thofe on the left fide receive the Lymphatics of the middle 
 and correfponding half of ihe Omentum Majus. Running to 
 the left tide of the large Curvature of the Stomach, and palling 
 through one or two fmall Glands on it, they go with the Lym- 
 phatics of the Spleen and Pancreas to the Thoracic Du£t. 
 
 Thofe of the right fide receive the Lymphatics of the corre- 
 fpondinc; half of the great Omentum, and alfo pafs through one 
 or two fmall Gland; which lie dole to the right Gaftric Artery. 
 
 In their defeent by the Pylorus, they meet the Plexus which 
 accompany the fuperior Coronary Artery, and run with them, 
 and with the deep Lymphatics of the Liver to the Thoracic 
 
 The Lymphatics of the Liver, as in other Vifcera, run in two 
 fets, the fuperncial of which are numerous, and unite into Trunks 
 in the manner Roots unite to form-, the trunk of a tree. 
 
 The fuperficiai and deep fets communicate To - freely-, that upon 
 inje&ing the Lymphatics on the external Surface, the deep-feated 
 Abforbents are readily filled from them. 
 
 The principal part of the Lymphatics upon the convex Sur- 
 face of the Liver, go by a right and left Plexus towards the Suf- 
 penfory Ligament. 
 
 Running along this Ligament they direftly perforate the Dia- 
 phragm, after which they pafs through Glands fituated upon the 
 anterior part of the Pericardium. 
 
 Other Lymphatics from the convex part of the liver run to- 
 wards the lateral Ligaments, where they form on each fide one or 
 more Trunks of confiderable fize. 
 
 From the lateral Ligaments they pafs through the Subfiance of 
 the Diaphragm, and afterwards run forwards on its convex Sur- 
 face, following the direclion of the Ribs. — Not ^infrequently. 
 
 Du&. 
 
J 62 
 
 tbei'e Veffels, in (lead of perforating the Diaphragm, run down- 
 wards and terminate in the Thoracic Duff, within the Abdo- 
 men. 
 
 In their courfe upon the Diaphragm, they often fend Branches 
 backwaids, which terminate in Glands upon the Efophagus ; 
 —in other inftances, thefe Branches are oblerved to go dire&ly 
 into the Thoracic Duft. 
 
 They receive Branches from the Subftance of the Diaphragm, 
 and, after perforating two or three Glands upon its Surface; 
 they join the Trunks from the Ligamentum Sufpenforium. 
 
 The Lymphatics from the lateral Ligaments, joined by thafe 
 from the Ligamentum Sufpenforium, form either a principal 
 Trunk, or a Plexus, which runs up, J'ometimes between the 
 Layers of the anterior Medialtinum, and, at other times, in com- 
 pany with the internal Mammary Bkod-veffels on each fide. 
 
 When this trunk or Plexus runs in the anterior Mediaftinum, 
 it mod fiequently terminates in the upper end of the Thoracic 
 Du£l; — fometimes, however, it communicates with the general 
 termination in the right fde of the Neck. 
 
 When they accompany the internal Mammary Veffels, they 
 are obferved to terminate, the left in the Thoracic Du£V, and 
 the right .n the general termination of that fide. 
 
 The Lymphatics on the concave Surface of the Liver run to- 
 wards the Poita, and join the deep-feated Set.— One part of them 
 goes over the under Surface of the Gall-bladder, from which 
 they receive numerous finall Branches. 
 
 The deep-feated Lymphatics accompany the Blood and Biliary 
 Vefieis, and community ing with the Superficial Abforbents al- 
 ready mentioned, they pafs through feveral Glands fituated 
 about the f lunk of the Vena Portae, and terminate in the Tho- 
 racic DtnTr, near the root of the fuperior Mefenteric Artery. 
 
 The Superficial Lymphatics of the Spleen are remarkably 
 finall. They pal's from its convex to its concave Surface, where 
 they join the deep-l'eated Lymphatics, which are very confidera- 
 ble in fize and number. 
 
 The Splenic Plexus of Lymphatics accompany the Splenic Ar- 
 tery, and go though feveral Glands of a dark colour fcattered 
 along the Surface of that Veffel. 
 
 The Lymphatics of the Spleen receive thofe of the Pancreas, 
 which run into them in a tranfverfe dire£tion. 
 
 In their courfe, they unite with the Lymphatics of the Stomach 
 and thole defcending from the under part of the Liver; and the 
 whole of them, near the head of the Pancreas, form a confidera- 
 ble Plexus. From this Plexus, Branches are fent off, fome paf- 
 fing over the Duodenum, and others under it, and all of them 
 going into the Thoracic Du£l near the termination of the Lac- 
 teals. 
 
 ] . . 
 
163 
 
 The Lymphatics of the Kidney are feldom feen, excepting when 
 it is enlarged or ulcerated, in which cafe they may lometimes be 
 diftirnflly obfetved. 
 
 The Superficial Abforbents run from its outer towards its in- 
 ner edge, where, meeting with thofe deep feated, they commonly 
 unite with them, and form a Plexus which accompanies the Renal 
 Blood-veffels, after which they pafs through fome of the Lumbar 
 Gland;, and terminate in large Lymphatics near the Aorta. 
 
 The Lymphatics of the Capfula Renalis, which are numerous 
 in proportion to its fize, terminate in the Renal Plexus. 
 
 All the Abforbents already defcribed, excepting ihofe from the 
 convex Surface of the Liver, terminate in the Thoracic Du£l 
 near its beginning. 
 
 The Thoracic Duff, at its under extremity, is formed by tbe 
 union of three, or fometimes of more principal Trunks, the firft 
 of which is ccmpofed of the Lymphatics of the right, and the fe- 
 cond of thofe ot the left Inferioi Extremity: — the third Trunk, 
 or fet of Trunks, belongs chiefly to the Lafteals. 
 
 Thefe large Abfoi bents unite fo as to form the Duff over the 
 th'rd Vertebra of the Loin?. 
 
 Sometimes they unite upon the fecond Vertebra of the Loins, 
 where the Duel formed by them is twice or thrice as large in dia- 
 meter as it is higher up. 
 
 Commonly it enlarges again upon tbe firft Vertebra of the 
 Loins, where it has generally been called the Receptacle of the 
 Chyle, and confidered as the beginning of the Du6l, being often 
 found forming an oval, or Pyriform bag, about the third of an 
 inch in diameter. 
 
 Thefe large Trunks which form the Thoracic Dufl lie clofe 
 upon the Spine, thofe of the right fide being-placed below the Right 
 Crus of the Diaphragm, and thofe of the left between the Aorta 
 and Spine, while the Thoracic Du£l itfelf lies at firft behind the 
 Aorta, but afterwards pafles from it upwards, and a l.ttle to the 
 right fide, till it gets before the firft Vertebra of the Loins. 
 
 Here it is fituated behind the Right Crus of the Diaphragm, a 
 little higher than the right Renal Artery, from whence it pafles 
 upwards, and afterwards appears in the Thorax, upon the fore 
 and right fide of the Spine, between the Aorta and Vena Azygos, 
 where it is fuppofed to be conliderably afiifted by the llrukes of 
 the Aorta in impelling its Fluids. 
 
 In the middle of the Thorax, it is fmaller than elfewhere be- 
 ing only about a line in diameter. After this it gradually en- 
 larges, and, near its termination, is about an eighth or tenth of 
 an inch over. 
 
 In the Thorax, it receives the Lymphatics of the Spatia In- 
 tercoftalia, one or two of which accompan : es e; ch of ne Inter- 
 coftal Arteries, and the whole go through final! Glands placed 
 
16 i 
 
 near thefe Arteries, but moil numerous about the (ides of the Dor- 
 fal Vertebrae, where they form a fort of chain. 
 
 Hue, likewife, it receives Branches from the Efophagus and 
 Lungs, the former of which is furrounded with a number of 
 Glands, and with a remarkable and intricate Plexus of Lym- 
 phatic Vefi'els. 
 
 The Superficial Lymphatics of the Lungs form large Areola:, 
 which have fmalier Areolae within them, the larger running chief- 
 ly between the Lobules, and the fmalier paffing over them in fuch 
 a manner as to cover almoft the whole Surface of the Lungs. 
 
 From the furface they go to the root of the Lungs, where they 
 pafs through the Bronchial Glands, which have already been ta- 
 ken notice of in the del’cription of the Lungs. 
 
 At this place they are joined by the deep-feated Lymphatics 
 which creep along the Blanches of the Trachea and of the Pul- 
 monary Blood-veflels. 
 
 Through the medium of the Bronchial Glands, the Lympha- 
 tics of the two fides of the Lungs communicate freely with each 
 other. 
 
 Having left the Glands, the principal part of thole from the 
 Left Lung form a Trunk of considerable (ize, which terminates 
 in the Thoracic Du£t, behind the bifurcation rT the Trachea. 
 
 The reft of the Abforbents of the left Lung pafs through 
 Glands behind the Arch of the Aorta, which are likewife com- 
 mon to thofe of the Heart. They run at laft by a principal Trunk 
 into the Thoracic Duft near its termination. 
 
 After leaving the Bronchial Glands, the Abforbents of the 
 right Lung form a few principal Trunks, one of which common- 
 ly afeends on the fore-part of the Vena Cava Superior, and, nin- 
 ning in a convcduted manner, opens into the Trunk which termi- 
 nates in the Veins in the right fide of the neck. 
 
 The reft of thele Trunks go into the Thoracic Du£V, near the 
 bifurcation cf the Trachea. 
 
 The Abforbents of the Heart are fmall, but numerous, and form 
 principal Trunks which accompany the Coronary Arteries, and, 
 like them, the largeft belong to the left Ventricle. 
 
 From the fide of the right Coronary Artery, an Abfor’oent 
 Trunk which correfponds with it, pafl'es over the Arch of the 
 Aorta to a Gland commonly found behind the origin of the Ca- 
 rotid Arteries 
 
 From this Gland it goes afterwards to the general termination 
 in the ride fide of the Neck. 
 
 The Lymphatic Trunk accompanying the left Coronary Arte- 
 ry is formed of two prr.cipal Blanches, one of which runs in the 
 Groove between the Ventpcks on the fuperior Surface of the 
 Heart : The other runs in a ftmilar Groove on the under fide 
 
 of the Heart, and having reached the fpace between the Auricles 
 
 ' ■ 
 
165 
 
 and Ventricles, turns round to join the former Branch near its 
 correfponding Artery. 
 
 The Trunk runs next to a Gland placed behind the Pulmona- 
 ry Artery, between the Arch of the Aorta and Root of the Tra- 
 chea, which, with the others here fituated, is common to the Ab- 
 i'orbents of the Heart and Lungs. 
 
 This Trunk terminates at length in the upper end of the Tho- 
 racic Duff. 
 
 The Thoracic Duel, after receiving numerous Lymphatics 
 within the Thorak, and having reached as high as the third or 
 fourth Dorfal Vertebra, paffes obliquely over to the left fide of 
 the Spine, behind the Efophagus and end of the Arch of the 
 Aorta, or beginning of the Aorta Defcendens, till it reaches the 
 left Carotid Artery. 
 
 After this, it emerges from the Thorax, and runs between the 
 Longus Colli Mufcle and Internal Jugular Vein, to about the 
 fixth Vertebra of the Neck. 
 
 It now makes a turn downwards, and, after defeending near 
 an inch, terminates in the upper and back part of the angle form- 
 ed by the left Interna Jugular and Subclavian Vein. 
 
 Throughout its whole couife, it has a waving appearance, and 
 this becomes more confpicuous in proportion as it is diftended by 
 injefiion. Near the middle of the Thorax, it not unfrequently 
 fplits into two or more branches, and fometimes forms a Plexus, 
 the Branches of which again unite into a common Trunk a little 
 higher up. 
 
 After emerging from the Thorax, it commonly divides into two 
 parts, which unite again previous to the termination of the Duft 
 in the red Veins j and where there is no dirifion, there ’is gene- 
 rally a Dilatation or Sac at the termination. 
 
 Sometimes there is one. termination in the angle formed by the 
 red Veins, and one or two in the Subclavian Vein, and now and 
 then, though more feldoro, in the Internal Jugular, near the an- 
 gle- . 
 
 I", a few instances, it has been found double through its whole 
 length, one Duff going to the common place of termination in 
 the left fide of the Neck, and the other in the correfponding part 
 in the right. 
 
 It has all'o, in a few rare instances, been found terminating in 
 the Vems in the right fide of the Neck, while a fhort Trunk, fi- 
 ir.ilar to that commonly found there, has terminated in the left 
 fide. 
 
 The Superior, in a Cmilar manner with the Inferior Extremi- 
 ties, hat - two lets of Lymphatics, one lying, immediately under 
 the Integuments, and. belonging to the Skin and Cellular Sub- 
 fiance u: it, tne other accompanying the principal Bloocl-vef- 
 
 feis, and ^longing ‘o the parts cieep-feated. 
 
 The Superficial Lymphatics are numerous, and are readily feen 
 in emaciated Sub j efts . 
 
166 
 
 They arife from the fore and back-parts of the Fingers and 
 hand, by a confiderable number of Branches, and form an ex- 
 tenfive Plexus upon the correfponding fides of the Fore Arm. 
 
 Thofe upon the anterior part of the Fore-arm run direfitiy up- 
 wards to the Arm, vvlvle the Lymphatics on its back-part, fepa- 
 rate into twofets, one of which paffes obliquely over the Muf- 
 cles on the Radius, and the other over thofe on the Ulna, to join 
 the Lymphatics on the anterior part of the Fore-Ai m. 
 
 The Lymphatics of the Fore- Arm mn over the bending of 
 the Elbow, and afterwards afcend upon the fore and inner part 
 of the Arm, the greater number of them running near the Balilic 
 Vein. 
 
 Some of them frequently pafs through fmall Glands placed 
 along the Humeral Artery, one of which is commonly found a 
 little above the inner Condyle of the Os Humeri, others do not 
 appear to enter any Glands till they reach thofe of the Axilla. 
 
 A few Lymphatics accompany the Cephalic Vein, and receive 
 Branches from the outer part of the Arm, and, after piffling be- 
 tween the Peftoral -and Deltoid Mufclcs, penetrate Glands at 
 the under fide of the Clavicle. 
 
 Of the deep-feattd Lymphatics, two commonly accompany 
 each principal Artery in the Fore-Arm, and thefe uniting at the 
 Elbow, form two principal Lymphatics, which accompany the 
 Trunk of the Humeral Artery. 
 
 Having reached the upper part of the Arm, they enter the Ax- 
 illary Glands, where they are joined by Lymphatics which come 
 from the Mamma and lateral parts of the Thorax, after palling 
 through fmall Glands placed upon the under edge of the former 
 and of tlie large Peiioral Mufcle. 
 
 Tile Axillary Glands vary in number and lize indifferent per- 
 fons. They are fomewhat fmaller, and fewer in number than 
 thofe of the Groin. They are generally furrounded by a confi- 
 derable quantity of Fat, and are fituated in the hollow between 
 the large PeiSloral and Latiffimus Dorfi Mufcles, adhering clofely 
 to the Trunks of the Axillary Blood- veffel's and Nerves. 
 
 From the Axillary Glands large Branches go under the Cla- 
 vicle, and form a Trunk, which, in the left fide, commonly joins 
 the Thoracic DatSl near its termination. In the right fide, they 
 join the fhort Trunk which forms the fecond general termination 
 of the Abforbent Syltem. Sometimes this Trunk, proceeding 
 from the Superior Extremity, terminates in the Subclavian Vein, 
 at a little diftance from the general termination. 
 
 Tlte Axillary Glands receive alfo the Subcutaneous Lym- 
 phatics from the back-part of the Thorax, and likewife the 
 Lymphatics from the Integuments and Mufcles of the Scapula. 
 
 The Lymphatics on the outjide of the Head accompany the 
 Blood-vefTds. and pafs through Glands in their wayy to the 
 Neck. 
 
i6 n 
 
 Thole palling down with the Temporal Artery go through 
 l'mall Glands connected with theParotid Gland, and alfo through 
 others fituated immediately under the root of the Zygoma. 
 
 The Lymphatics which accompany the Occipital Blood-vefTels 
 penetrate one or two minute Glands placed a little behind the 
 root of the Ear, over the Maftoid Prccefs of the Temporal 
 Bone. 
 
 The Lymphatics proceeding from tjie different parts of the Face 
 accompany the Branches and Trunk of the Facial Artery. 
 
 Some of them pafs through Glands fituated upon the outfide 
 of the BuccinatorMufcle, while the principal Trunks go through 
 a number of large Glands placed upon, the outer, and alfo at the 
 under part of the Lower Jaw, at the anterior edge of the Mafl'e- 
 ter Miifcle, and about the Inferior Maxillary Gland. 
 
 The Lymphatics from the inner fart of the Nofe run principal- 
 ly with the internal Maxillary Artery, and pafs through Glands 
 fituated behind the Angle of the Lower Jaw, where they are 
 joined by thofe which belong to the inner parts of the Mouth. 
 
 The Lymphatics of the Tongue , and likewife of the Mufcles 
 and other parts obout the Os Hyoides, enter the Glands placed 
 behind the angle of the Lower Jaw. 
 
 Lymphatics have been frequently fearched for in the Brain, 
 but their exiftence in that Organ is not yet fully afcertained, 
 though rendered highly probable,— from an appearance of Lym- 
 phatics 'having been now ar.d then obferved upon the Surface of 
 the Dura Mater, and between the Tunica Arachnoides and Pia 
 Mater,— from Lymphatics and Glands being octafienaily found 
 in, or immediately on the outfide of the Palfages of the Blood- 
 veffels of the Brain, — fiom fwellings in the Lymphatic Glands 
 of the Neck, following dd'eafes of the Brain, — from the Ab- 
 forption of Water, which has fometimes happened in Hydroce- 
 phalous cafes, and — from their having been found on the Brain 
 of Fifhes. 
 
 From the Superficial and deep parts of the Head in genera], 
 the Lymphatics accompany the External and Internal Jugular 
 Veins and the Carotid Arteries, receiving at the fame time Branch- 
 es from the Mufcles and other parts of the Neck. 
 
 The principal part of thefe Lymphatics go along with the In- 
 ternal Jugular Vein and Carotid Artery, and in their paffage 
 form a remarkable Plexus,' which goes through the numerous 
 Glands feated near the Blood-vefTels, compofing a chain, from 
 which they are termed Concatenate. 
 
 The Glandule Concatenate are more numerous than any other 
 fet of Glands in the Body, excepting thofe which belong to the 
 Mefentery,. 
 
 The Cervical Plexus of Lymphatics having paffed through the 
 Glandulae Concatenatae, unite at the bottom of the Necklnto a 
 Trunk, which, in the left fide, enters the Thoracic Du& near 
 
168 
 
 its termination, and in the right, goes into the Trunk, which 
 forms the general termination of that fide. 
 
 The Trunk which forms this general termination is only from 
 a quarter to half an inch in length, but its fize not much lefs than 
 that of the thoracic Du£l. 
 
 It is formed by Lymphatics from the right fide of the Liver, 
 Diaphragm, Heart, and the right Lobe of the Lungs, by thofe 
 of the right Arm, right fide of the Head, Neck, and Thyroid 
 Gland ; the Lymphatics of the left fide of the Thyroid Gland 
 forming a trunk which ends in the Thoracic Du£t. 
 
 Befides this common Termination, fome of thefe Lymphatics 
 occafionally open into the Internal Jugular, or into the Subcla- 
 vian Vein, at a little diftance from the angle formed by thefe two 
 Veins. 
 
 
 y 
 
16 § 
 
 PART VI. 
 
 OF THE 
 
 BLOOD-VESSELS IN GENERAL . 
 
 // 
 
 — /> 
 
 The Blood-Vessels are divided into Arteries and Feins. 
 
 Arteries. 
 
 ^"The Arteries are eladic Canals, which convey the Blood from 
 th^.Heart to the different parts of the Body, and are dillinguifh- 
 ed from the Veins by their Pulfation. 
 
 They have obtained their name from the Ancients, fuppofing 
 that they carried the finer parts of the Blood mixed with Air,— 
 forming what they coniidered the Animal Spirits. 
 
 The Original Trunks of the Arteries, or thofe which arife 
 from the Heart, are two in number, viz. the Pulmonary Artery 
 and Aorta,— all the others being derived from thefe. 
 
 They are difperfed over the whole Body, and are every where 
 furrounded with Cellular Subftance. 
 
 The principal Trunks run in the Centre of the Body, or of the 
 Extremities, where they are lead expofed to danger,— deriving 
 fupport or defence from the Bones along which they pafs. 
 
 The largelt Arteries goto the Fifcera, within the great Cavi- 
 ties, the fmaller ones to the Skin and Mufcles , and thofe dill 
 fmaller to the Bones, — and, in a few places, they become fo ex- 
 tremely minute as altogether to exclude the red Blood, carrying 
 a colourlefs Fluid only. 
 
 The Arteries are didinguifhed, in the Subject, from the Veins, 
 by the nvbitenefs of their Colour and thicknefs of their Coats. 
 
 They are compofed of different Layers or Coats, which are rea- 
 dily feparated by Dilfeftion. 
 
 VoL. II. P 
 
170 
 
 In feveral parts of the Body, as in the Pojlerior Mediafiinum, 
 'they are l'urrounded by a Membrane, common to them and to 
 ■the neighbouring Vitcera. 
 
 In other parts of the Body, efpecially in young Subjefts, they 
 are furrounded with to much Cellular Subliance, as to give them 
 the appcaiance of being mclofed in Sheaths, 
 
 The fill! of the proper Coats is the External Membranous , or 
 Cellular, called alio by fonie Authors the Nervous Coat. 
 
 In the large Arteries, this Coat is frequently furnilhed with 
 Eats, and is of a very elaJHc nature. Owing to this elalficity, 
 the Arteries, in receiving the Blood from the Heart, become di- 
 lated and elongated, and ftart from their place, in confequence 
 .of wh.ch they form the Pulfe, called alfo the Diajlole of the Ar- 
 teries. 
 
 The Second, or Middle Coat, is compofed of Fibres Tunning 
 in a ivanfverfe direftion, — pf a pale red colour, — each Fibre ap- 
 pealing to form only the Segment of a Circle, although the 
 whole conftitute a Cylinder round the Artery. 
 
 By the Contradhlity of this, and the elaltic nature of the for- 
 mer Coat, the Arteries are enabled to drive the Blood to the 
 Veins, in proportion as tiiey receive it from the Heart ; — and this 
 Contra&ion is called the Syflole of the Arteries. 
 
 The Third, ox Inner Coat, is formed of a tranfparent Mem- 
 brane, remarkably thin, 1'mooth, and denle, by which the Blood 
 is pi evented from traniuding. 
 
 The different Coats of the Arteries are conne£led to each other 
 by line Cellular Subdances, which l'ome Authors have confider- 
 *d as fo many Lamellse. 
 
 The Arteries are fupplied with their own Blood -veffels, termed 
 Yafa Caforum, which come from the nearell fmall Branches, and 
 .are every where dtl'perfed upon their external Surface. 
 
 They have alfo their Lymphatics, which, on the large Arte- 
 ries, as the Aorta, are fo numerous as l'ometimes tq. cover them. 
 
 They are likewiie furnilhed with fmall Nerves, forming, in 
 feme parts of the Body, a Plexus, which vanilhes in their ex- 
 ternal Coat. 
 
 There are no Calves belonging to the Arteries, excepting 
 thofe which are placed at the mouths of the Pulmonary Artery and 
 Aorta. 
 
 Where the Arteries run a certain way without fending off 
 Branches, they are obfetved to be of a Cylindrical form ; but 
 ■where Branches come off, their Capacity is diminifhed, and this 
 in proportion to the number of their Ramifications. 
 
 Whenever an Artery divides into two Branches, the Areas of 
 thefe two Branches, taken conjunflly, are found to be nearly 
 one half larger than that of the Trunk from which they iflue. 
 
 When the Trunk and Branches of an Artery are regarded col- 
 JeStvely, they appear evidently of a Conical figure, the point of 
 
the Cone being formed by the Trunk, and the Balls by the 
 Branches of the Artery. 
 
 The Seftion of the Arteries is circular; — when empty, they 
 become flit, but recover their round form upon being diftended 
 by inje£l ion . 
 
 The angles at which the Branches go off from their Trunks 
 are in general in proportion to their vicinity to the Heart, and are 
 fuch as are mod favourable to the parts they have to f.pply. 
 
 In the Trunk of the Body, or where they belong to tender and 
 delicate Vifcera, the angels are moreobtufe; — in the Extremities, 
 'they are more acute, the former circumftance tending to dimimfh, 
 and the latter to increafe the force of the Blood. 
 
 The Arteries form many Divifions and Subdivifions before 
 they reach their Terminations, and at lilt become invihbie to the 
 naked eye. 
 
 The Divifions formed by suy particular Artery have been va- 
 rioufly enumerated by different Authors.— one reckoning I'nCm. 
 •«t forty, and another, of equal refpeef ability, at twenty only ; — 
 the number of them, however, is fuch as to allow them to fup- 
 ply the raoft minute parts of the Body. 
 
 The ftrength of the Arteries depends upon' the thicknefs of 
 their Coats, which is found to vary in different Arteries. — In the 
 Aorta, the Coats are thick and ftrong ; — In the Arteries of the 
 BrairTand Spleen, they are thin and teudei ; — but the thicknefs 
 and confequent ftrength are propoi tionably greater in the fmall 
 Branches than in the lar,e Trunks. 
 
 The Arteries run more or lei's in a waving dire&ion, which 
 breaks the force of the Blood in them, and p; events them from 
 being drained by the motions of the. parts to which they belong. 
 
 The Flexions are rnoft frequent in Arttyies belonging to 
 parts the fize and iltuation of which are changeable. 
 
 The windings of many of the Arteries are in proportion to the 
 degree in wb'ch they are diftended, thoi'e which are nearly ftraight 
 in theft- natural date, frequently becoming lerpentine when their 
 diftenfion increafes. 
 
 Several of the large Arteries form communications with each 
 other, termed by Anatomifts Anajlomofes ; but the Anaftomofes 
 are more frequent among the fmail Branches, where they form £ 
 Plexus which leffens the danger of obftruclion. 
 
 Tite Anaftomofes are moft frequent in the Skin and Membra- 
 nous Parts. In the folid Vifcera, the Arteries run in a different 
 manner, being in fome crowded together in the form of Trees or 
 Bufhrs, in others hiving a ferpenrine appearance, and in feveral 
 forming Pen ici 11 i , or little Brufties, according to the difpofitioa 
 of the part. 
 
 The Arteries obtain their particular names from their fixa- 
 tions, place of deft nation, &c. and the term Capillary , as ex- 
 prefiive of their fmallnefs, is applied to their minuteft Blanches. 
 
172 
 
 The Diameters of the different Trunks and Branches of the 
 Arteries, vary much in different parts of the Body ; but thofe 
 of the Capillaries are more nearly equal to each other. 
 
 The Arteries terminate in the following manner, viz. 
 
 In red Veins, as is obferved by the affiftance of the Microfcope 
 and by Inje&ions : 
 
 In Glands or Follicles by Secretory Dufts, which feparate a 
 Fluid from the general Mafs of Blood. 
 
 In Exhalent Veffels, which difeharge their contents into the 
 internal Cavities, or upon the external Surface of the Body. 
 
 In colourlefs or Lymphatic Branches, which are afterwards 
 continued to the circulating Veins, as in the Cartilages and 
 Cornea. 
 
 The Ufe of the Arteries is : 
 
 To convey Blood from the Heart to the different parts of the 
 Body : 
 
 To affift in converting the Chyle into Blood : 
 
 To nourifh the Body, and promote its growth : 
 
 Toaffiftin preferving the fluidity of the Blood, and the heat 
 and life of the Body : 
 
 To form the different Secretions : and 
 
 To renew the growth ®f parts deftroyed by accident or difeafe. 
 Veins. 
 
 The Veins are elaftic flexible Tubes, returning the Blood from 
 the different parts of the Body to the Heart, — and have no Pul- 
 fation. 
 
 The Coats of the Veins are the fame in number with thofe of 
 the Arteries, but are thinner, denfer, and lefs elaftic. 
 
 In the large Veins, as the Vena Cava, the Coats can be fepa- 
 rated from each other but in the ftnall Branches their repara- 
 tion is difficult. 
 
 The Mufcular Coat of the Veins being much thinner, loofe 
 like Cellular Subftance, and more indiftinft than that of the Ar- 
 teries, has cccafioned its exiftence to be denied by many Au- 
 thors. 
 
 The Veins are alfo furnilhed with their Vafa Vaforum , fimi- 
 lar to and from the fame fource with thofe of the Arteries. 
 
 The C.olour of the Veins is fomewhat blue, and when full of 
 Blood they appear of a purple tinge, in confequence of their 
 thinr.efs. 
 
 Their Size is more than double that of the Arteries to which 
 they belong, excepting the Pulmonary Veins, the ftze of which 
 fcarcely furpaffes that of their correfpond ing Arteries . 
 
 In the fleffiy pa' ts of the Body, part'cularly in the Extremities, 
 they conftft of Tjvo Sets, one deep-feated accompanying the 
 Arteries, the other running immediately under the Skin, and 
 termed Subcutaneous. 
 
173 
 
 The Veins of the Thoracic and Abdominal Vifcera in general, 
 accompany their Arteries; and the lame is obfervable in the 
 fmall Branches belonging to Membranous parts. 
 
 The Figure of the Veins is fimilar to that of the Arteries ; and, 
 upon comparing the Area of their Tiunks with the coileflive 
 Area: of their Branches, like them too, they are perceived to be 
 Conical, the Bafe of the Cone being formed by the Branches, 
 and the Apex by the Trunks. 
 
 The fize and number of the Veins is fo much greater than that 
 of their correfponding Arteries, that when the Vcffels of a Mem- 
 branous part are diftended by an Injeftion of different colours, 
 the Veins are obferved in a great meafure to conceal the Arteries : 
 —In the Inteftines however, the number of the Arteries and 
 Veins is nearly equal. 
 
 There is much greater variety among the Trunks of Veins, 
 with refpeft to fituation and divifion into Branches, than is ob- 
 fervable among the Arteries. 
 
 The variety in Nature is fuch, that the Veins of every Sub- 
 ject differ a little from thofe of another. 
 
 ( The Veins are capable of buffering greater didenfion than the 
 Arteries, yet aie more frequently ruptured. 
 
 The Analtomofes are greater and more frequent in Veins than 
 in Arteries, thofe of the former being frequently by large 
 Tiunks, whereas thofe of the latter, excepting in a few places, 
 are by fmall Branches only. 
 
 Where the Veins are expofed to Mufcular nftion, they are 
 furnifhed with Valves, which are fern' lunar Folds continued from 
 the inner fide of the Veff.ls, and placed in pairs at irregular 
 didances their nature being fimilar to thofe of the Abforbents. 
 
 Tne Valves are concave towards the Heart, and when clofed or 
 applied to each other, reprefent a figure fomewli3t like that of 
 the fhut end of a thimble. 
 
 Between the Valves and Sides of the Veins next the Heart, the 
 Bloo 1 infimiates, and Cavities are formed, termed Sinujes of the 
 Valves, which appear externally in the form of Varices. 
 
 The Valves are found in the flefhy parts of the Body in gene- 
 ral, but are chiefly fituated in the Veins of the Extremities. 
 
 They arc awanting in the Veins of the deep-feated Vifcera, viz. 
 in thofe of the Cranium, Thorax, and Abdomen, excepting 
 the Spermatic Veins, and fometimes the Internal Mammary 
 Veins, and the Branches of the Vena Azygos. 
 
 The Valves diieff the Blood towards the Heart, and prevent 
 Regurgitatioa. 
 
 The life of the Veins is — 
 
 To convey the Blood from the extremlt'es of the Arteries, 
 with the Chyle and Lymph, from the Abforbents to the Heart. 
 
 P 2 
 
 VOL. II. 
 
DISTRIBUTION OF THE BLOOD VESSELS. 
 
 Of the Pulmonary Artery and Veins. 
 
 The Pulmonary Artery arifes from the right Ventricle of the 
 Heart, and afcends behind the Sternum, and within the Pericar- 
 dium, inclining-a little to the left. 
 
 Having run as high as the concave fide of the Arch of the 
 Aorta, it divides into ri.ht and left lateral Branches, which 
 terminate in the correfponding tides of the Lungs. 
 
 The right Branch pafies behind the curvature of the Aorta and 
 the fuperior Vena Cava, and is of courfe the longer of the two. 
 
 The two Branches are difperfed throughout the fubftance of 
 the Lungs, by ramifications which accompany thofe of the 
 Bronchi. 
 
 From the extreme Branches of the Pulmonary Artery, the 
 Blood is returned by coirefponding Veins. 
 
 The Pulmonary Veins run contiguous to the Arteries, and un- 
 like the other Veins in general, are nearly of the fame fize with 
 their Arteries. 
 
 In their courfe, they unite into larger Branches, which at 
 length form four principal -Trunks, — two from the right, and 
 two from the left Lung, — which after perforating the Pericardi- 
 um, terminate in the left Auricle of the Heart. 
 
 General Courfe of the Aorta and Vena Cava. 
 
 The Aorta arifes from the left Ventricle of the' Heart, and 
 fends off, at its Origin, the Coronary Arteries formerly defcri- 
 bed . 
 
 Where it takes its origin, it turns a little, to the right, and is 
 afterwards direfled upwards, backwards, and towards the left 
 fide. 
 
 It afcends as far as the top of the Thorax, under the name of 
 Aorta Afcendens, and is afterwards reflefled obliquely back- 
 wards over the root of the left Branches of the Trachea, forming 
 what is termed Curvature, or Arch of the Aorta. 
 
 It then commences Aorta Defcendens , which runs down clofe 
 upon the Spine, till it reaches the fourth Vertebra of the Loins, 
 where it divides into the two Iliac Arteries. 
 
 The Thoracic portion of the Aorta Defcendens is fituated on 
 the fore and left part of the Spine, between the Layers of the Pof- 
 terior Mediaftinum. 
 
 Where it pafies from the Thorax to the Abdomen, it goes be- 
 tween the long Crura of the Diaphragm, after which it defcends 
 more immediatly upon the fore-part of the Vertebrae, 
 
175 
 
 The Aorta fends off Arteries wli'ch cany Blood to the differ- 
 ent parts of the Body, from whence it is returned by Veins to the 
 Inferior and Superior Vena Cava, — excepting what paffes to the 
 Coronary Veficls. 
 
 The Inferior Ca-va is formed by the union of the two Venae Ili- 
 •acae, upon the lalt Vertebra of the Loins, a little below the Ter- 
 mination of the defcending Aorta. 
 
 It is fituated upon the foie-part of the Spine, and at the right 
 fide of the Aorta, which it accompanies for a considerable way- 
 through the Abdomen. 
 
 Near the upper end of the Abdomen, it recedes from the Aor- 
 ta, and paffes behind the large Lobe of the Liver. 
 
 It perforates the Diaphragm in its Tendinous part, and hav- 
 ing entered the Pericardium, it goes immediately into the right 
 Auricle of tlte Heart. 
 
 The Inferior Cava receives the Blood from the Inferior Extre- 
 mities, from the Pelvis and Abdomen, and carries it to the 
 Heart. 
 
 The Superior Cava , — formed by the union of the two great 
 Venae Subclaviae, with the addition of the Vena Azygos, — s fi- 
 tuated in the upper part of the Thorax, upon the right fide of, 
 and a little more anteriorly than the afcending Aorta. 
 
 It begins behind the Cartilage of the firft Rib, fomewhat 
 higher than the Arch of the Aorta, and has at firft afmall incli- 
 nation towards the right fide. 
 
 After defcending about an inch, it perforates the Pericardium, 
 and having run down nearly twice this lpace, it enters the Right 
 Auricle, oppofite to the termination of the Inferior Cava. 
 
 The Superior Cava -receives the Blood from the Head, Neck, 
 Arms, and containing parts of the Thorax, and all'o carries it to 
 the Heart. 
 
 BLOOD-VESSELS of the HEAD, and PART of 
 THOSE OF THE NECK. 
 
 Arteries. 
 
 From the upper fide of the Arch of the Aorta, three large 
 Arteries arife, which fupply the Head, Neck, and Superior Ex- 
 tremities. 
 
 Of theie three Arteries, one on the right fide, termed lnnomi- 
 nata, foon divides into the Right Carotid, and Right Subcla- 
 vian Artery. 
 
176 
 
 The other two are the Left Carotid, and Left Subclavian, 
 which tom£-xifFin feparate 7 lunks. 
 
 Cafotid Arteries : The Carotid Arteries, after emerging 
 from the Thorax, run up on each fide of the Neck, between the 
 Trachea and Interna! Jugular Veins, and behind the Sterno- 
 mattoid Mufcles, gradually receding from each other. 
 
 In the Neck, they do not lend off any Blanches till they reach 
 the top of the Larynx, where each, oppofite to the Os Hyoides, 
 divides into External and Internal Carotid Artefes ; the former 
 fupplying the outer parts ot i lie Head, the other the Brain. 
 
 The External Carotid is placed more anteriorly, and 
 nearer the Larynx, than the Internal, which lies deeper, and is, 
 at its Rout, the larger of the two 
 
 7'he External, though frrinller than the other, appears as a 
 continuation of the common Trunk. 
 
 It runs up behind the angle of the Lower Jaw, and in its paf- 
 fage hcfoie the Ear towards the Temple, is funk deep in the fub- 
 ftance of the Parotid Gland, which it fupplies with Blood, and is 
 divided into the following pi incipal Branches, viz. 
 
 The Arteria Laryngea Superior, Gutturalis Su- 
 perior, or Thyroidea Superior, which comes off from the 
 Root of the External Carotid, and fometimes fiom the top of the 
 common Carotid. 
 
 Itpafl'es downwards and forwards in a winding dire&ien, and 
 fends 
 
 Branches to the Mufcles about the Os Hyoides ; — 
 
 To the Mufcles, Jugular Glands, and Skin near the Larynx;— 
 and 
 
 To the different parts of the Larynx itfelf, the continuation 
 and principal part ot the Artery terminating in the Thyroid 
 Gland. 
 
 The Arteria Lincualis, which is fent off immediately 
 above the former. — It goes forwards and upwards over the cor- 
 vefponding Cornu of the Os Hyoides, and under the Hyo-gloffus 
 Mufcle, in a direction towards ihe under and fore-part of the 
 Tongue. — ft gives 
 
 A final 1 Branch to the Pharynx ; — 
 
 A Branch, termed Ramus Hyoideus, to the Mufcles placed be- 
 tween the Tongue and Larynx ; — 
 
 The Dorfalts Lingua; to the Fauces, Amygdala, Epiglottis, 
 
 &c.— 
 
 The Ramus Sublingualis , which comes off under the middle of 
 the Tongue, and is difperfed upon the Sublingual Gland and ad- 
 jacent Mufcles ; — and 
 
 The Ramus Ra/tinus, which is the p; incipal Branch of the 
 Lingual Artery, running at the under and lateral part of the 
 Tongue, and terminating near its point. 
 
177 
 
 Tfie Ar.ter.ia Facialis, Maxillaris Externa, Labi a- 
 LIS, or Angularis, which alio runs forwards, and goes under 
 the Stylo-hyoid, and Tendon of the Digaftric Mufcles. It per- 
 forates the Submaxillary Gland, mounts fuddenly over the angle 
 of the Lower Jaw, at the underand fore-part of the Mafl'eter 
 Mufcle, from whence it proceeds in a tortuous manner towards 
 the inner corner of the Eye. 
 
 In this courfe, it fends the following Branches to the adjacent 
 parts. 
 
 The Palatina Inferior , which runs upwards upon the fide of 
 the Pharynx.— 
 
 A Branch to the Tonfil, &c. — 
 
 Branches to the Inferior Maxillary Gland ;— 
 
 Small Branches to the root of the Tongue, to the Skin, Muf- 
 cles, &c. near the angle of the Jaw ; — 
 
 The A. Submentalis, which runs forwards under the Bafe of 
 the Lower Jaw, furnifhing Branches to the parts near it, and ter- 
 minating on the middle of the Chin ;— 
 
 Upon the outfide of the Jaw,— a Branch to the Maffeter Muf- 
 cle ; — 
 
 While upon the Buccinator Mufcle,— Branches to the Cheek 
 and to the lower part of the Under Lip ;— 
 
 Near the corner of the Mouth, — the A. Coronaria Inferior to 
 the Under Lip ; and a little higher,— 
 
 The Coronaria Superior to the Upper Lip, from whence 
 Branches run to the under part of the Partition and Point of 
 the Nofe. 
 
 The Coronary Arteries run near the edge of the Lips, where 
 meeting with their fellows of the oppofite fide, they form an A, 
 Coronaria Labiorum. 
 
 Frequently one or both Coronary Arteries are larger than or- 
 dinary, in which cafe thofe enthe oppofite fide are proportionally 
 fmaller. 
 
 After fending off the Coronary Branches, the Facial Artery 
 runs near the wing and fide of the Nofe. 
 
 From this part of the Artery Branches are fent inwards to the 
 Nofe, and outwards to the Cheek. 
 
 The Facial Artery is at laid loll upon the parts about the inner 
 corner of the Eye, and middle of the Fore-head. 
 
 The Phary n gea Inperior, whch is a fniall Artery arifing 
 near the Lingual Artery, and frequently from the root of the Oc- 
 cipitalis. 
 
 After afeending fome way, it divides into Branches, which 
 are difperled upon the Pharynx, Fauces,. and Bafe of the Skull, 
 where fi.me of them enter the large Foramina, and fupply part 
 of the Dura Mater. 
 
 The A. Occipitalis, which arifes from the back-part of the 
 External Carotid, and at its origin is concealed by the other ori- 
 ginal Branches fent off from that Aitery, 
 
178 
 
 It runs ever the beginning of the Interna] Jugular Vein, and 
 afterwards paffes under the Maftoid Procefs, and pofterior Belly 
 of the Digaftric Mufcle. 
 
 It goes likewife under the upper ends of the Trachelo-maftoi- 
 deus, Splenius, and Complexus Mufcles ; after which, it be- 
 comes more fuperficial, where it runs near the middle of the Oc- 
 ciput. 
 
 In its courfe, it is very tortuous, and gives off different Bran- 
 ches to the furrounding Mufcles : viz. 
 
 One which defcends along the Sterno-maftoid Mufcle, and 
 communicates with the Thyroid, Cervical, and Vertebral Arte- 
 i ies ; 
 
 Another which paffes, with the Jugular Vein, to the underand 
 back-part of the Dura Mater i 
 
 A Twig, through the Foramen Stylo-maftoideum, to different 
 parts of the Internal Ear : 
 
 A Branch which proceeds to the back-part of the Ear, under 
 the name of Auricularh Pcjlerior -and 
 
 Another, of confiderable 1 ze, which defcends between the Tra- 
 chelo-maltoideus and Complexus Mufcle?, and, after bellowing 
 Twigs upon feveral Mufcles of the Neck, communicates with 
 the Cervical and Vertrebral Arteries. 
 
 The Artery is at laft difperfed upon the beginning of the Oc- 
 cipito-frontalis Mufcle, and Skin of the Occiput, where it com- 
 municates with its fellow, and with the Temporal Artery. 
 
 Sometimes, a Twig of this Artery paffes- to the Dura Mater, 
 through that final! Irole occalionally found near the Maftoid 
 Procefs of the Temporal Bone. 
 
 ■ 7'he A. Maxillaris Interna, which goes off from that 
 part of the Trunk which is covered by the Parotid Gland, and at 
 its origin lies behind the middle of the upright Plate which di- 
 vides into the Condyloid and Coronoid Proceffes of the Lower 
 Jaw. 
 
 It paffes far ft between the Jaw and External Pterygoid Muf- 
 cle, and afterwards runs, in a very winding manner, towards the 
 back-part of the Antrum Maxillare, fending numerous Branches 
 to the Parts belonging to both Jaws. 
 
 At its origin, it furnifhes Twigs to the fore-fide and adjacent 
 parts of the outer Ear. 
 
 It then lends off the A. Dura Matris Media Maxima, Menin- 
 gca, or Spheno-fpir.alis, which runs between the External and In- 
 ternal Carotids, paffes through the Foramen Spinale of the 
 Sphenoid Bone, and fpreads over the furface of the Dura Mater 
 and infide of the Paretal Bone, like the Branching of a Tree. 
 
 The Inferior Maxillary Branch, which runs in the Inferior 
 Maxillaiy Canal, fending Branches to the lubftance of the Bone, 
 and to the Teeth ; — the remainder of it paffmgout at the Ante- 
 
119 
 
 rior Maxillary Foramen, and communicating upon the Chin with 
 Branches of the Facial Artery. 
 
 Branches to the Pterygoid, Maffeter, and inner part of the 
 Temporal Mufcle, under the names of A. Pterygoidea, Majfe- 
 t erica, and 7 emporales Profunda : 
 
 The A. Buccales to the Buccinator Mufcle and other foft parts 
 of the Cheek. 
 
 The A. Alajealares, which run behind the Antrum, and fend 
 Branches to the foft parts furrounding the Upper Jaw.— The 
 Maxillary Artery fends other Branches which enter by fmall 
 Holes to the Antrum, and to the Subltance and back-teeth of 
 the Jaw ; one of whicli is larger than the reft, and is the Proper 
 Al<veolaris. 
 
 The lnfra-orhitar, which pafles in the Cana! under the Orbit, 
 giving, at its entrance, Twigs to the foft parts in the bottom of 
 the Orbit, and in its progrefs, other Twigs to the Antrum, Sub- 
 ftance of the Jaw, and Fore-Teeth ; after which it goes out at 
 the Foramen Infra-crbitarium, and terminates on the Cheek by 
 fmall Branches which communicate with thofe of the Facial Ar- 
 tery- 
 
 The P alato-maxillary Branch, which paftes through the Fo- 
 ramen Palatinum Porter ius, and runs between the OfTeous and 
 Fielhy parts of the Palate, fupplying thefe with Branches, and 
 frequently proceeding through the Foramen Incifivum to the in- 
 ner part of the Ncle. 
 
 The Superior Pharyngeal, which is a fmall Branch terminating 
 in and about the upper part of the Pharynx. 
 
 The Large Lateral Nafal, which enters the Foramen Spheno- 
 palatinum, and divides into many Branches which fupply the 
 greater part of the in fide of the Nofe. 
 
 A. Temporalis. — The Trunk of the External Carotid, 
 having given off the Arteries already mentioned, pafles up be- 
 tween the Meatus Auditorius and root of the Zygoma, and forms 
 the Temporal Artery, named alfo Temporalis Externa, or Super- 
 ficialis from the root of which are lent off, 
 
 The Pranfv erf alls Faciei, which proceeds forwards under the 
 Zygoma, fupplying a large portion of the Cheek, and communi- 
 cating with the Facial and Infra-orbitar Arteries : 
 
 Some fmall Branches to the Articulation of the Jaw : 
 
 Several fmall Branches to the root of the Ear, part of which 
 are difperfed upon the External Meatus and Membrana Tym- 
 pani, — I'ome Twigs penetrating as far as the inner Ear. 
 
 A little above the root of the Zygoma, where the Puliation 
 of the Temporal Artery can be felt, and frequently even leen, it 
 divides into two large Branches, an Anterior, and Pofierior, 
 which are placed fuperficially between the Integuments of the 
 Head and Aponeuroiis of the Temporal Mufcle, 
 
180 
 
 The Anterior. Branch proceeds forwards, in a Terpentine 
 direftion, to the fide and upper-part of the Forehead, fupplying 
 the Skin and Mufcles near it, and communicating with Branches 
 of the Facial and Occular Arteries, and with thofe of its Fellow 
 on the oppofite fide of the Head. 
 
 The Posterior afcends obliquely backwards, giving a few 
 Branches to the upper part of the Ear, but is chiefly difperfed on 
 the Integuments and Mufcles upon the lateral part and crown of 
 the Head, communicating with its fellow of the fame and of the 
 oppofite fide,' and alfo with the Occipitalis, by numerous Ramifi- 
 cations. 
 
 Internal Carotid Artery. 
 
 The Internal Carotid, — fometimes termed^. Cerebra- 
 Jis ,~ is arched back at its origin, and then afcends in a waving 
 direftion on the fore-part of the Reftus Capitis Anterior Major 
 Mufcle, as far as the Foramen Caroticum, without giving ofP 
 any Branches. 
 
 At the Bafe of the Cranium, it makes a fudden turn forwards, 
 and enters the Carotic Canal of the Temporal Bone : While in 
 the Canal, it pafles upwards and forwards, like the Canal itfelf, 
 and is furrounded by a confiderable quantity of Cellular Sub- 
 ftance, and by the Dura Mater, which form a Cufiiion between it 
 and the Bone. 
 
 After leaving tire Canal, it again bends upwards and then for- 
 wards, by the fide of the Sella Turcica ; and perforating the Du- 
 ra Mater, at the root of the Anterior Ciinoid Procefs, it is fud- 
 denly reflected obliquely backwards and upwards, after which it 
 diviJes into Branches. 
 
 Through the whole of its courfe, it runs in a Terpentine man- 
 ner, which prevents the Blood in it from rufhing too quickly 
 and forcibly upon the tender Subftance of the Brain, and, — con- 
 trary to the nature of other Arteries, — it is of a Conical form, 
 though it does not fend off any Branches, till it enters the Cra- 
 nium. — 
 
 Wh'Je at the Side of the Sella Turcica, it furniftes fmali 
 Twigs to the Dura Mater and parts adjacent, one of which pafles 
 through the Foramen Lacerum to the Orbit, and another, accom- 
 panied by a fimdar Twig from the Meningeal Artery, through 
 the Pais Petrola, to the Tympanum, 
 
 As foon as the Carotid perforates the Dura Mater, at the root 
 ef the Ciinoid Procefs, it tranfmits 
 
 The Arteria Ophthalmica, which is the principal Ar- 
 tery belonging to the Eye and its Appendages. 
 
 The Ophthalmic, or Ocular Artery, immediately after it comes 
 off from the Carotid, enters the Foramen Opticum, and creeps 
 under the Optic Nerve, included in the Dura Mater, towards 
 the outer part of the Orbit. 
 
13 l 
 
 After proceeding fome way through the Oj bit, it traverfes its 
 Cavity, taking a Spiral direction towards the Nul'e, between the 
 Optic Nerve and Mufcles in the upper part of the Orbit. 
 
 In tiiis courfe, it tirft tranfmits Filaments ter the Dura Mater 
 and Subftance of the Opri ; Nerve, arid to the beginning of the 
 Mul'closin the bottom of the Orbit, after which it gives off the 
 following Branches, viz. 
 
 Toe Arteria Lacry mails, which rur.s at the outfide of the Or- 
 bit, and is chiefly ldpeif 1 upon the Lacrymai Gland, fume 
 Threads advancing to he E . e-lids : 
 
 The A. Cent’ alls Ret ins, which penetrates the Optic Nerve a 
 little behind the Bali of the Eye — runs in the centre of the 
 Nerve, and fpreads out into many fmall Branches upon the infide 
 of the Retina. 
 
 When the Nerve is cut acitofs, the orifice of the divided Ai tery 
 is ohfcrvable, which, before its nature was underltood, was 
 long known by .the name of Fonts Opticus. 
 
 In the Adult, the Central Artery_appears to terminate entirely 
 upon the Retina 5 but in the Foetus, after furnifiling, at the bot- 
 tom of the Orbit, the Branched proper to the Retina, the Trunk 
 is continued forwards through the axis of the Vitreous Humour, 
 flip p lying its Cells and Membrane with delicate Filaments, and 
 afterward. -.breading but upon the back-part cf the Capfule of the 
 Lens. 
 
 Its Branches are difperfed upon the Lens in a radiated manner, 
 and after furrounding it, fome of them are lent forwards to the 
 Membrana Pupil laris. 
 
 File Arterise Ciliares , — two or fometimes mare in number, — 
 which divide into Branches running in a terpentine direction a- 
 loug the onpolite iides of the Optic Nerve, and dividing into the 
 Ci Wares Breves, and Ciliares Longa?. 
 
 The Ciliares B'e-ves, or Pofteriores, — -formed not only of 
 Branches from the original Ciliary Trunk, but alfo of Twigs 
 from she Mufcular Branches, — are numerous. They perforate 
 the Sclerotica, near the infertion of the Optic Nerve, give Twio-j 
 to that Coat, and dividing into ftill fmalfer Branches, creep for- 
 wards upon the Tunica Choruides, — forming many Communica- 
 tions with each other 3 $ they advance, and retiring gradually from 
 the convex to the concave l'urface of this Coat to luppiy the Iris 
 and Ciliary Proceffes. 
 
 The Ciliares Longs, — which feldom confi.ft of more than two 
 Trunks, — perforate the Sclerotica a little farther forwards than 
 the former, pat's along the Choroid Coat to its anterior part, and 
 then feparate into Branches. 
 
 -Befides the Ciliares Breves et Longae, there is another Set, 
 termed Ciliares Anteriores, which are a few Arterious Filaments 
 from the MufcularBranches, entering the Eye where the Straight 
 Mufcles are inl'erted. 
 
 Vol. II. Q 
 
1S2 
 
 At the root of the Iris, the different fets of Ciliary Arlenes 
 unite into Arches, which form an irregular Circle, called Circulus 
 Iridis. 
 
 From this Circle, many Arteries run upon the Iris, in a radia- 
 ted terpentine manner, towards the Pupil, near wh ; ch fcveral of 
 them al-fo unite into Arches ; and from thefe, Twigs are font, 
 along with the red of the radiated Branches, to the inner edge cf 
 the Iris. — In the Foetus, they are continued to the Membrana 
 Pupillaris. 
 
 The Mufcularis Superior, and Inferior, which are dilperfed 
 upon the Muteles and Fat of the Eye. 
 
 The C Ethnioidalis Anterior, and Pojlerior, two extremely fmall 
 Twigs, elpecially the latter, which pafs through the Foramina 
 Orbitaria Interna, — Anterius, et Poderius, — to the Bones and 
 Membranes of the Nofe. 
 
 The Supra- orbitalis , or Frontalis, which, emerging from the 
 Socket, partes through the Foramen Supra-orbitat turn, and is 
 divided into two pans ; — one dilperfed upon the Periodeum of 
 the Fore-head, the other running to the Skin and Muicles on the 
 Fore-head and upper Eye-lid, and communicating with the an- 
 terior Branch of the Temporal Artery. 
 
 The remains of the Occular Artery are continued to the inner 
 angle of the Eve, and are difperfed upon the Eye-lids, Lacrymal 
 Sac, fide of the Nofe, and Frontal Mul'cle, communicating with 
 the upper end of the Facial Artery. 
 
 Arteries of the Brain. 
 
 The Arteries of the Brain conrtd of the two Internal Carotids, 
 and the two Vertebi als. 
 
 Each Internal Carotid, after fending forwards the Ocular Ar- 
 tery, gives a Branch backwards to the Vertebral, termed A. Com- 
 municans, and then divides into the A. -Anterior, and A. Media 
 Cerebri. 
 
 The A. Anterior Cerebri, turns towards its fellow of 
 the opportte fide, and commonly fends Filaments to the Fitft and 
 Second Pair of Nerves. 
 
 A little before the union of the Optic Nerves, the right and 
 lef t anterior Cerebral Arteries become aimed contiguous, and 
 anaftomofe by means of a fltort, but large tranfveife Branch, 
 which forms part of that Communication of Veffels termed Cir- 
 cus Arteriofus Willisii. 
 
 From this tranfverfe Branch, but more frequently front the 
 Anterior Cerebral Artery near it, a Branch is lent off, which paf- 
 fes into the Third Ventricle, and furn'fhes Twigs to the Septum 
 Lucidum, and fore-part of the Fornix. 
 
 The Anterior Cerebral Artery alcends upon the inner fide of 
 the anterior Lobe of the Brain, and lends off a principal Branch, 
 
133 
 
 and commonly another Toon after, both of which arch backward! 
 upon the inner flat furface of tire Hemifphere. 
 
 The continuation of the Anterior Cerem al Artery is termed 
 A. Corporis Callo/t, and is relieved back upon the union of the: 
 Corpus Caliofum and Hemifphere, as far as the poiierior Lobs 
 of the Brain, 
 
 The Branches of the Anterior Cerebral Artery at e divided in- 
 to minute Ramifications, which are fin'd fpread out upon the flat 
 furface of the Hemifphere, arid afterwards upon its upper part. 
 
 The Ramifications form mimberleJs Anallomofes with each 
 other upon the furface of the Brain,. and afterwards oafs, by mi- 
 nute Filaments, into it: Cortical and Medullary Sub fiance. 
 
 Befides the AnalKunoihs of the different Branches of this Ar- 
 tery on the furface of the Hemilphevc, final 1 Branches run acrofs 
 the Corpus Caflofum, and inofculate with thofe of the oppofite 
 ride. 
 
 The Arteria Media Cerebri,— which is larger than the 
 former,- — runs outwards in a lateral direction through the FoJJ'a 
 of Sylvius, to the 6utei part of the Brain. 
 
 It gives frit Fi. aments tu the GlanHula Pitu t tria and parts, 
 adjacent to it, and then divides into principal Branches, of which 
 one let go to the Anterior, and the other to the Lateral and part 
 of the Pofterior Lobe of the Brain. 
 
 From this Aitery, one or two Twigs run up into the anterior 
 Cornu of the Lateral Ventricle, and aflift in forming the Choroid 
 Plexus of that Cavity. 
 
 Upon the outer furface of the Brain, theBranches of this Af- 
 ter}' inofculate with each other, and with thofe of the Anterior 
 Cerebral- Artery, and then plunee into the lubffance of the Brain, 
 where they meet with the deep Branches of that Artery. 
 
 \ Verteeral Arteries. 
 
 The two Vertebral Arteries , — which are only a little fmaller 
 than the Internal Carotids, — arife from the Subclavian Arteries 
 at the bottom of the Neck. 
 
 Each of them, at a final! difiance from its origin, enters the 
 Canal formed for its reception by the fix uppermost Cervical Ver- 
 tebrae. 
 
 It alcends through the Neck, nearly in a [Haight direflion, 
 fending Twigs outwards between the Veitebiae to the deep Muf- 
 cles of the Neck, and others which pais inwards to the Spinal 
 Marrow and its Membranes, by the Holes which tranfmit the Spi- 
 nal Nerves. 
 
 Immediately below the Plead, it gives out more confitiernble 
 Branches to the deep Mufcies at the back-part of the Neck, which 
 inofculate with the Occipital Artery. 
 
 At the upper part of the Neck, it forms Contortions fomewhat 
 fimiiar to, and anfweriug the fame purpol’e with thole of the In- 
 ternal Carotid Artery. 
 
18 + 
 
 One turn is formed upwards and outwards, in palling from the 
 third to the iecond Vertebra ; and another outwards and for- 
 wards, in going between the iecond Vertebra and Atlas, 
 
 After perforating' the Atlas, it bends fudden'ly back, and tuns 
 in an horizontal direction in a Notch upon that Bone. 
 
 Ha ving reached the Foramen Magnum Occipitis, it turns up- 
 wards, perforates the Dura Mater, and enters the Cavity of the 
 Cranium. 
 
 After entering the Cranium, it pafies with the Medulla Ob- 
 longata, ypon the Cuneiform Procefs of the Occipital Bone, in- 
 clining towards its fellow on the other fide, and at the beginning 
 of the Medulla, the two Vertebrals unite into the Trunk called 
 Eafilar Artery. 
 
 Upon entering the Skull, each Vertebral Artery fends a fmall 
 Branch, termed A . Meningea Pofierior , — to the pofterior part of 
 the Dura Mater. 
 
 It then difperfes Twigs to the Medulla Oblongata, and fre- 
 quently gives off the fmall Branch which forms the Pof.erior Ar- 
 tery of the Spinal Manow. 
 
 Near the part where it unites with its fellow, it fends down the 
 Anterior Artery of the Spinal Marrow. 
 
 From the Vertebral, or from the Bafilar, or fumetimes from 
 each, a principal Branch is fent off, named A. Cerebelli PoJIerior, 
 or Inferior , which pafies between the Cerebellum and Medulla 
 Oblongata, and furnifhes Branches to the under part of the 
 Cerebellum, to the back-part of -the Medulla Oblongata and 
 Tuber Annulare, and forms the Choroid Plexus of the Fourth 
 Ventricle. 
 
 The Basilar Artery runs along the middle of the Tuber 
 Annulate, which it (lightly impreffes, and lies upon the Cunei- 
 form Procefs of theOcc.pital Bone. 
 
 From the Tides of this Artery, numerous Filaments run tranf- 
 verfely, to be difperfed upon the Tuber and adjacent parts 
 
 One Branch, larger than the reft, called Auditoria Interna, paf- 
 fes between the two portions of the Seventh Pai r of Nerves to 
 the Internal Organ of Hearing. 
 
 At the extremity of the Cuneiform or Bafilar Procefs of the 
 Occipital Bone, and at the upperand fore-part of the Tubar An- 
 nulare, the Bafilar Artery divides into four principal Branches, 
 two to each tide, and thefe go off almoft at light angles from the 
 Trunk, viz. 
 
 The A. Superior, or Superior Cerebelli, which turns round the 
 Crura Cerebri, expands its Branches upon the upper part of the 
 Cerebellum, and finks into its fubfiance, fupplying alio the 
 Nates, Tellies, and Parts near them. 
 
 The Artcria Pof.erior Profunda Cerebri, which fends Twigs to 
 the Tuber and to the Cru.a Ceiebi'i, and unites with the Internal 
 Carotid by the Atteria Communicans. 
 
It fuppUes alfo Parts lying near the Third Ventricle, and af- 
 tei wards turning round the Crura Cerebri, paffcs back, between 
 the Cerebrum and Cerebellum. 
 
 It ddtributes its numerous Branches chiefly to the Poifenor 
 Lobe of the Brain, one Branch in particular penetrating into t lie 
 posterior Cornu of the Lateral Ventricle, and with Branches of 
 the Internal Carotid, forming the Arterious part of the Choroid 
 Plexus. 
 
 The Branches of this Artery 3naftomofe with thofe of the an- 
 terior part of the Internal Carotid, at the infide of the Hemif- 
 phere, — and with thole of the lateral part of that Artery, at the 
 outfide of the Heinifphere, in the manner thefe do with each other 
 in the other parts of the Brain. 
 
 The Arteria Communicam , which unites the pofterior Cerebral 
 Branch of the Vertebral Artery to the Trunk cf the Internal 
 Carotid, and is nearly of the fame diameter, but longer than that 
 tranfverfe Artery which conne£ds the anterior Branches of the 
 Internal Carotid. 
 
 It lends minute Threads to the Crura Cetebri, See. and con- - 
 tributes to the formation of the Circle of Willis, — or that kind 
 of Communication by which the blood or Injefled Matter can 
 pafs readily acrofs from one Internal Carotid to the other; — or 
 from thele backwards to the Bail la r Artery. 
 
 Veins of the Head and of Part of the Neck. 
 
 The V sins which return the Blood from the Arteries of the 
 Head and Neck, unite into the following Trunks, viz. 
 
 • ; -e Facial Vein, which ds formed by the Frontal Ve.n, and 
 l / an intricate Plexus of Branches upon the Face. 
 
 It winds obiiquely downwards and outwards, at a diftxnce 
 r. om the Artery ; but in crofting the Jaw, it goes clofe by the 
 outride of it, and terminates in the External jugular Vein., 
 
 The ‘Temporal Vein, formed by l'uperficial and deep Branches 
 ’rom the tides and upper part of the Head, and uwnaig do wn 
 upon the Temple at fo me diftance from the Artery. 
 
 The Blanches of the Temporal Vein form large Anaftom. fes, 
 before, with thofe ot the F.ontal Vein; above, with their fel- 
 lows oa the other fide; and behind, with the Branches of the 
 Occipital Vein. 
 
 The Trunk defeends at the fore-part of the Ear, and, along 
 v ith the Artery, is funk in the fubitar.ee of the Paiotvd Gland. 
 
 In its descent before the Meatus Auditor us Externus, it re- 
 ceives Branches fiom the Ear, Parotid Gland, and Cheek, cor- 
 iefpondin r with the A: teries fent to thele Part* front the Carotid 
 or Temporal Artery. 
 
 At the under part cf the Lower Jaw, the Facial and Tempo- 
 ral Veins commonly unite and form the External JugaJar. 
 
The External "Jugular Vein receives the following branches at 
 the iijipei part of he Neck, viz. 
 
 Branches of the Internal Maxillary Vein, the principal part 
 term! ating in the Internal Jugular. 
 
 'The Lingual Vein, one Branch of which, termed Ranina from 
 its complexion, is fcen under the Tongue, and is that Vein 
 which i- opened in the Venel’eflion of this Organ. 
 
 Branches of the Occipital Vein, the reft palling to the Internal 
 Jugular, and Verve ral Vein,, and fometimes alfo communica- 
 ting by a For:. men Mallo'deuin with the Lateral Sinus. 
 
 The Trunk of the External Jugular Ve : n tlefcends in the 
 Neck, between the P-latyfma Mymdes and Sterno-maftoid Muf- 
 cles, receives in its couife Branches from the adjacent parts, and 
 terminates in the Subclavian Vein. 
 
 In the formation and termination of this Vein, there is great 
 vaiiety in different Subjects. 
 
 It .frequently happens that me ft of the Ramifications, which 
 commonly run from the Face and Throat into this Veit), go to 
 the Internal Jugular. 
 
 Often the Facial Vein goes into the Internal Jugular, and the 
 Temporal continued forms the External Jugular. 
 
 Sometimes one of the External Jugulars terminates in the 
 ufual way, and the other mi the Internal Jugular. 
 
 In feme rare cafes, the External jugulars have both been 
 found terminating in one fide of the Neck. 
 
 Anterior External Jugular Vein. Bcfides the Vein commonly' 
 called External Jugular, a fmall Subcutaneous Vein, termed 
 Anterior External Jugular , defeends in the fore-part of the 
 Neck, receiving Bl anches from the adjacent parts, and termina- 
 ting in the Subclavian Vein. 
 
 Veins of the Eye and its Appendages. 
 
 The Blood fentto the Contents of the Orbit is returned paif- 
 ly to the Facial Vein at the inner corner of the Eye, but chiefly 
 to the proper Ocular Vein, which terminates in the Cavernous 
 Sinus by the following Veins, viz. 
 
 'The- Vena Centralis Retina, which is formed by many fmall 
 Branches expanded upon the inner furface of the Retina along 
 with thofe of the coi refponuing Artery. 
 
 The Vena Centralis enters the Optic Nerve, where the Artery 
 leaves it ; and a little behind the Ball of the Eye, it emerges from 
 the Nerve, and runs between it and the Sheath which covers it, 
 receiving many Twigs from the Nerve and its Membranes. 
 
 It paftes afterwards tinder the Fafciculus of Nerves which be- 
 longs to the Eye, and terminates, fometimes in the Ocular Vein, 
 but, in general, dire£lly in the Cavernous Sinus. 
 
 Front the Iris and Chorohl Coat, the Blood is returned by the 
 Short or Anterior Ciliary Veins, and by the Long or Lcjierior 
 
1ST 
 
 Ciliary Feins, and alfo by a principal let of Ciliary Veins, termed 
 Faja Fo'ticofa. 
 
 Small Veins return from the Iris, winch go under the Arteri- 
 ous Circle to the Veins of the Choroid Coat, and communicate' 
 with each other ; — ‘but without forming any Circle, fueh as is 
 found in the Eyes of Oxen, and which correfponds, in them, with 
 the Arterious Circle. 
 
 The Anterior Ciliary Feins pafs from the Iris through the Scle- 
 rotic Coat, near the fame part where the Anterior Ciliary Arte- 
 ries enter. 
 
 The long biliary Feins are commonly two in number, like the 
 Arteries, and of a fmaller ft ze than the Vorticofe Veins. 
 
 They run from the Iris backwards along the Choroid Coat 
 Communicate in their palTage by minute Branches with the Vorti- 
 cofe Veins, and afterwards perforate the Tunica Sclerotica be- 
 hind. 
 
 The Feutz Forticofiz, are numerous, and obtain their name 
 from the Whirls compofed by their Branches, the courfeof which 
 has been compared to a Jet d'eazi, or to the Spiral Ridges upon 
 the points of the Fingers, &c. 
 
 Of thefe Veins, four, or fometlmes five, are by much the null 
 confpicuous, the reft being fmaller, and having lei's of the Vor- 
 ticofe appearance. 
 
 The Branches of each of the four principal Vente Vorticol’se 
 run in a clofe congeries, unite at acute angles into lam er Branch- 
 es which have a curved direftion, and thefe proceeding from all 
 fides, meet in a point, and form the Trunk of the Vein. 
 
 The Trunks of thefe Vense Vorticofae, thus placed in the cen- 
 ter of their refpe£live Whirls are fituated at the oppoiite fides of 
 the Eye, and perforate the Sclerotic Coat obliquely near its mid- 
 dle. 
 
 The rejl of the Fenee Forticofae, or fmaller Ciliary Veins, com- 
 municate with the adjacent larger Vorticofe Veins upon the fur- 
 face of the Choroid Coat, and alfo perforate the Sclerotica near 
 its middle. 
 
 After piercing the Sclerotica, the different Vorticofe Veins 
 unite into four or five fmall Ciliary Trunks, receiving a number 
 of minute Twigs, which paint the Cellular Subltance covering 
 the furface of the. Sclerotica. 
 
 The Ciliary Veins run in a ferpentine direction at the oppo- 
 fite fides of the Eye, and pafs either l'eparately or united with 
 other fmall Veins in the Orbit, into the tiunk of the Ocular 
 Vein. 
 
 The other Venous Branches within the Orbit, correfpond in a 
 great meafure with their refpe£tive Arteries ; fuch as, 
 
 Branches from the Palpebrae and inner corner of the Eye, 
 
 i he Lacrymal Branch : 
 
 The 0 Ethmoidal Branches : 
 
133 
 
 Mufcular Br anches, — and Branches from the Fat in the Orbit, 
 and from the Membranes lining it. 
 
 The different Branches from the Eye and its Appendages form, 
 by their union, the Ocular Fein, which greatly exceeds the fize 
 of ihe correfponding Artery. 
 
 The Ocular Vein forms large Anaftomofes, at the inner cor- 
 ner of the Eye, with the Facial Vein, and afterwards paffes back 
 at the inner fide of the Oihit. 
 
 From the inner, it goes acrofs to the outer fide of the Orh : t, un- 
 der the Attollens MufcJe ; and after runniiu hack under the An- 
 terior Clinoid Procel's, coveied by the Third and Sixth Pai, of 
 Nerves, it terminates, under the Carotid Artery, in the Ca- 
 vernous Sinus. 
 
 Veins of the Dura Mater Corresponding with its 
 Arteries. 
 
 The Veins of the Dura Mater accompany their Arteries, and 
 go partly through Perforations in the Bnfe of the Cranium, to 
 terminate in Branches of the External or Internal Jugular Veins ; 
 — the reft go into the neaieft Sinufes ©f the Brain. 
 
 Veins of the Brain. 
 
 The fmaller Veins of the Brain accompany the Arteries. 
 Their Trunks run chiefly between the Cii cumvolutions of the 
 Brain, at a diftance from the Trunks of the Arteries. 
 
 They terminate in the differerent Sinufes of the Dura Mater, 
 and generally in an obhque dueflion, which prevents the Blood 
 from returning into them. 
 
 The Sinufes mull commonly found are t he following. 
 
 The Superior Longitudinal Sinus, which begins at the under 
 part of tile Spine of theFiontal Bone, runs along the upper edge 
 of the Falx,— and becoming gradually wider, terminates upon 
 the middle of the Occipital Bone, in the. two Lateral Sinufes. 
 
 It receives the Blood from the upper part of the Bra n, by feve- 
 ral large Venous Trunks, which enter it obliquely forwards. 
 
 The • Torcular tleroj hili, or Fourth Sinu of the Ancients, 
 chic fly firmed by the Venn Gain', which returns the Blood 
 from the Choioid Plexus, C i .ora Striata, Septum Lucidum, 
 and other Internal pair- of the Brain. 
 
 The Port clai pafles back in the joining of the Falx and Ten- 
 toriur , and tet initiates, along with the Superior Longitudinal 
 Sinus, i . i he beg:! r.ir.g ■ f the Lateral Sinufes. 
 
 TP-. I'ji 'or ):nftii<l\ til Sinus, a remarkably final] one, fit th- 
 at - i in the u nd 1 i; - lie Falx. — It receives Btai cues from 
 
 that Mu i ’ i‘m C us Callofum and pans of 
 
 the r.. ' and ij;i : : es in the beginning of tht Torcu- 
 lar el. _ .* 
 
 -. ' v - ' Shaft:, or S'tafnd and Third Sinufes of the 
 dinal and Torcular Sinus. 
 
189 
 
 They run at the pofterior edge of the Tentorium, along the 
 lateral ridges of the Os Occipitis, as far as the Bale of the Pe- 
 trofal Procelles of the Temporal Bones, from whence they wind 
 downwards, pafs through the Foramina Lacera common to the 
 Occipital and Temporal Bones, and terminate in the Internal 
 Jugular Veins. 
 
 Frequently one of the Lateral Sinufes is formed by the 
 Longitudinal, and the other by tile Torcular Sinus ; in which 
 cale, the one is found larger than the other. 
 
 The Lateral Sinufes receive Veins from the Cerebellum and 
 from the under and back-part of the Cerebrum ; they luce- 
 wife receive the Blood from the following frnnll Sinufes, lituated 
 under the Brain, viz. 
 
 T-he Circular Sinus of Ridley, which is placed abaut the 
 Glandula Pituitaria, and frequently furrounds it completely, re- 
 ceiving the Blood from it and from the adjacent Bones and 
 Membranes, and terminating in the Cavernous Sinufes: 
 
 Tile Cavernous Sinufes, which are lituated at the tides of the 
 Sella Turcica, and receive Blood from Veins lying near the lateral 
 Blanches of the Internal Carotid Arteries, from the Octriar Veins, 
 and from the Circular Sinus of Ridley : 
 
 The Cavernous Sinufes furround the Carotid Arteries and 
 Sixth pair of Nerves, and have a Cavernous ftru&ute within, 
 fomewhut refembling that of the Penis : 
 
 The Superior Fetrofal Sinufes, lituated upon the Ridges of the 
 Partes Petrol’s. 
 
 They receive fome finall Veins from the Dura Mater and Bale 
 of the Brain, and communicate backwards with the Lateral, and 
 forwards with the Cavernous Sinufes: 
 
 The Inferior Fetrofal Sinufes, placed at the roots of the partes 
 Petrols. — They receive the blood from the Cavernous, and dif- 
 charge it into the ends cf the Lateral Sinufes. 
 
 Befides the Smufts mentioned above, the following others are 
 frequently met with, viz. 
 
 A Perpendicular Occipital Sinus, lituated in the Falx Cerebelii, 
 wh'ch is fometimes lingle, fometimes double, and terminates in 
 the Lateral Sinufes.— It receives Veins from the Dura Muter, 
 and communicates with the Vertebral Veins. 
 
 Anterior Superior, and Anterior Inferior Occipital Sinufes, pla- 
 ced over the Cuneiform-Pro els of the Occipital Bone, and com- 
 municating with the Inferior Petrolal and Lateral Sinufes, ar.d 
 with the Vertebral Veins. 
 
 Internal Jugular Veins. 
 
 The Lateral Sinufes, having received .the Blood fent to the 
 Brain from the Carotid and Vertebral Arteries, pafs out cf the 
 Cranium, and form the Internal Jugular Feins ; each of which, 
 at its origin is bulged back in form of a- Varix, which is termer: 
 
190 
 
 Diverticulum and this is lodged in a Foffa at the root of the Pars 
 Petrofa of the Temporal Bone. 
 
 The Internal Jugular Vein defcends behind the Sterno- 
 maltoid Muffle, upon the fore an i outer part of the Common 
 Carotid Arte;)', with which it is included in a Sheath oi Cellular 
 Subftance ; and is frequently a good deal dilated towards its un- 
 der Extremity, efpeciaily in advanced life. 
 
 In its courts in the Neck, it icccives 
 
 Branches from the Pharynx and Mufcles adjacent to it: 
 
 The Internal Maxillary Vein : 
 
 One or more Branches from t lie Occiput: 
 
 The Lingual Fein, which fometimes terminates in the External 
 J tigular : 
 
 Ehe Superior Laryngeal, and now and then the Inferior La- 
 ryngeal, w hick more frequently goes into the Subclavian, or to 
 the top of the Cava. 
 
 The Internal Jugular alfo receives Branches from the Mufcles 
 cl the Neck, and at length ie: ruinates in the Subclavian Vein. 
 
 The remaining Blood-Vessels of the Neck., with thoi'e of 
 the Superior Extremity in General. 
 
 Arteries. 
 
 Subclavian Artery. The Suhclavian Artery has been 
 already obl'eryed to a,ril'e on the right fide, in common with 
 the Carotid : and on the left, to come oft' direftly from the 
 ' Aorta. 3 
 
 After the Artery leaves the Thorax, it paffes tranfverfely out- 
 wards at the under part of the Neck, behind the under end of 
 the Sterno-malloid Mui'cle, anil continues its collide outwards be- 
 tween the Anterior and Middle Scaleiii Mufcles, and between 
 the Subclavian Mufcle and fir ft Rib. 
 
 After eroding the fi-rft Rib, it goes under the Pectoral Mnf- 
 clea to the Axilla, .where it obtains the name of Axillary Artery. 
 
 ' — Ei this court., it lends oft the following Branches, viz. 
 
 I he Vertebral — The Internal Mammary ; ap.d — The Supe- 
 rior l ntercojial Artery , — The 'fir ft of thefe has been already de- 
 ienbed ; the two others belong to the inner part of the Thorax. 
 
 The Th yroidea, or Gutturalis Inferior, which ari- 
 fes at tlie outer tide of the Vertebral, and, afeending obliquely 
 inwards behind the Carotid Artery, gives Branches to the Tra- 
 chea and Efophsgus, and Mufcles near them ; but is chiefly dif- 
 ptrfcd upon the Thyroid Gland, communicating by large Ana- 
 ftomofes with the Larynt ea Superior. 
 
 The Cervicalis Anterior, which frequently comes oft 
 from the root ol the Inferior Thyroid, and afeends in the 
 Neck, furnifoing fnperficial Branches to the Mufcles which 
 
191 
 
 go from the Trunk of the Body to t'ne Neck, and d-;ep Bl anch- 
 es to the Glands, Nerves, No. lying on the fore and lateral 
 parts of t tie Cervical Vertebrae. 
 
 The Deep Branches . analcomofe with the Vertebral and Oc- 
 cipital Arteries ; and fome palling through the Intervertebral 
 Holes where the Nerves come out, communicate with the Spinal 
 Arteries. 
 
 The Cervic.alis Posterior, which arifes in common with 
 the Anterior Cervicalj or with the Inferior Thyroid. — This is 
 larger than the foimtr, lies farther out, and runs in a winding 
 direction outwards and upwards. 
 
 It fupplies the Skin and Mufcles at the lateral and back-part 
 of the Neck, communicates with Branches of the Occipital and 
 Vertebral Arteries, and fends a principal Branch downwards to 
 the parts about the top of the Shoulder. 
 
 The Dorsalis Superior Scapula, which comes fre- 
 quently from the root of the Thyroid, and running tranfverlely 
 behind the origin of the Sterno-maftoid Mufcle, near the Clavi- 
 cle, — perforates the Notch in the iuperior Cofta of the Scapula, 
 and expanding its Branches upon the Dorf'um of that Bone, fup- 
 plies the Spinati and other Mufcles fuuated there, and likewife 
 furnifhes Branches to the joint of the Shoulder. 
 
 The Axillary Artery, lying in the Axilla, and furround- 
 ed by the Lymphatic Glands and Fat, and by the large Nerves 
 which form the Brachial Plexus. The Axillary Artery, gives 
 fome fmail Branches to the parts adjacent ; — but its principal 
 Branches are. 
 
 The Thoracic.®:, or Mammaries Extern.®, — three bi- 
 four in number, — which, by fome Authors, are defcribed by par- 
 ticular names ; as, 
 
 The Iboracica Superior, which gives Branches to the Pc£io- 
 rales and Serratus, and fome to the Intercoftal Mufcles : 
 
 The Thoracica Longa, which fends Twigs to the Axillary 
 Glands ; but goes chiefly to the large Pectoral Mufcles, Mam- 
 ma, and Integuments, and inolculates with the Branches of the 
 Thoracica Superior. 
 
 The Iboracica Humeralis, or Thoracic Artery of the Shoulder, 
 which goes off oppofite the Thoracica Superior, and divides fud- 
 denly into Branches which run tp the upper parts of the Thorax 
 near it, and to the Mufcles and Integuments lurrounding the Ar- 
 ticulation : 
 
 The Thoracica Axillaris, which, when prefent, goes off from 
 or near to the Thoracica Humeralis, and is bellowed upon the 
 Glands, Fat, See. frequently difperfing Branches upon the under 
 edge of the Subfcapularis Mufcle. 
 
 The Scapularis Interna, which foon divides into the 
 Proper Scapular-is Interna and the Dorfalis Scapula Inferior. 
 
The Scapularis Interna runs near the inferior edge of the Sca- 
 pula, fends off many large Brandies, the principal part of which 
 ate difperfed upon the Latiffimus Dorfi, Teres Major, and Sub- 
 fcapularis Mufcles, and have large Anaftoniofes with each other, 
 and with the Superior Dorlal Artery of the Scapula. 
 
 The Dorsalis Scapulje Inferior, immediately after lea- 
 ving the Internal Scapulary Artery, turns round the inner edge 
 of rite Scapula, a little below its Cervix. 
 
 Upon the Pofterior Surface of the Scapula, it fpreads out into 
 Branches of conftderable fize, which are difperfed upon the Muf- 
 cles covering the under and back-part of the Bone ; while the 
 Trunk, afcending, inofculates with that of the Superior Dorlal 
 Artery of the Scapula, whereby an Arch common to the two Ar- 
 teries is formed at the root cf the Acromion. 
 
 The Cikcumflexa Anterior, or Articularis, which 
 pafks in a tranfverle direction between the Heads of the Coraco- 
 bracitialis and Biceps Mufcles, and Body of the CC Humeri, 
 immediately below the Joint of the Humerus. 
 
 The Cikcumflexa, or As ticularis Posterior, which 
 nrifes dire&ly oppofite to the fqrmef, and is by much the larger 
 of the two. 
 
 It paffes firfl between the Subfcapularis Mufcle and Teres Ma- 
 jor, and then turns round between the back-part of the Os Hu- 
 meri, and long Head of the Triceps, and the Deltoid Mufcle, and 
 is djfpeifed upon the Deltoides and parts about the Joint ; — its 
 extreme Branches anallomofng with thofe of the Anterior Cir- 
 cumflex Artery, fo as completely to encontpafs the Body of the 
 Bone. 
 
 After giving <'1T thefe different Branches, the Axillaiy Artery 
 emerges from behind the edge of the great Peftoi al Mufcle, and 
 runs along the Os Humeri, where it is termed Humeral or Bra- 
 chial Artery. 
 
 Thu Humeral Artery defeends behind the inner .edge cf 
 the Biceps Mufcle, covered by the Tendinrus Apaneurofis of 
 the Arm, and having the Triceps Extenfor Cubiti behind. In 
 this couife, it bellows Branches to the Mufcles and Integuments, 
 and to the Periolicum and Bor.e, v'z. 
 
 The Profunda Humeri, or Spiralis, which arifes near 
 the upper part of the Arm, at the tnfertion of the Latiffimus 
 Dorfi and Teies Major Mufcles, taking a Spiral di rift ion down- 
 wards and outwards, between the Triceps Mufcle and Bone, and 
 terminating at the outer Condyle of the Os Ilumeri. 
 
 The Arteria Profunda fends Branches chiefly to the Coraco- 
 brachialis and Triceps Mufcles, and to thofe at the outer part 
 of the Elbow ; — md one of them, defeending at the inner fide of 
 ti.c Arm, is fometimes fo conftderable as to form — 
 
 The Profunda Inferior or Minor. This Artery is fic- 
 quentiy a Branch of the Profunda Superior, but mote commonly 
 
193 
 
 an orig : nal Branch lent off from the Trunk of the Artery, near 
 the middle of the Arm. 
 
 It gives Branches to the Mufcles and other parts at the infide 
 of the Arm, and terminates about the inner part of the Os Hu- 
 meri. 
 
 The Ramus Anastomoticus Magnus, which comes off 
 a little above the-'Elbow, and bellows Branches to the Brachialis 
 Interims, to the under end of the Triceps, and to the Parts in 
 general about the Elbow-Joint. 
 
 Beiides thefe, there are feveral other Branches fentin fucceflion 
 from the Trunk of the Humeral Artery into the Mufcles and o- 
 ther parts adjacent. — Thefe are Ihorter than the reft, and run 
 more in a tranl’verfe direction, efpecially thofe to the Biceps Muf- 
 cle. — One fmall Branch, termed Nutritia, or Medullaris, pene- 
 trates the fubftance of the Bone by the paffage near its middle, 
 and fupplies the Marrow and Parts which contain it. 
 
 The Trunk of the Humeral Artery having fent of the differ- 
 ent Branches which belong to the Aim, paffes to the middle of 
 the bending of the Elbow, between the Aposeurofis and round 
 Tendon of the Biceps Mufcle. 
 
 About an inch below the Elbow, it commonly divides into two 
 principal Arteries, the Radial and Ulnar. It happens, however, 
 now and then, that this Divifion takes place about the middle of 
 the Arm ; and in certain inftances, as high as the Axilla. 
 
 The Radialis paffes over the Pronator Teres Mufcle, and 
 follows the courfe of the Radius through the whole length of that 
 Bone 
 
 At the upper part of the Fore-arm, it is covered by the Supi- 
 nator Longus : In its defeent, it becomes more fuperficial, and, 
 at the under part of the Fore-arm, it lies clofe upon the Radius, 
 and immediately under the Skin, in confequence of which, the 
 Pulfe is commonly felt in this place. 
 
 The Recurrens Radialis, which is refletted to the Muf- 
 cles and Parts of the Joint near it, and anaftomofes freely with 
 the Arteria Profunda Humeri at the outer part of the Elbow. 
 
 Numerous Lateral Branches, in the defeent of the Artery, to 
 the Mufcles and Integuments, and parts in general lituated about 
 the Radius. 
 
 A Branch at the Wrift, which goes over the root of the 
 
 Thumb, and fometimes a principal Branch along one fide of it; 
 
 at other times, it is difperied upon the Palm of the Hand. 
 
 Small Branches to the Ligaments, Bones and other parts about 
 the Wrift. 
 
 One, or fometimes two Branches, termed Dorfal, to the back- 
 part of the Metacarpus and Fingers. 
 
 At the under end of the Fore-arm, the Radial Artery turns 
 back under the Tendons of the Extenfors of the Thumb, and 
 Vol. IL R 
 
194 
 
 gets between the roots of the Metacarpal Bones of the Thumb 
 and Fore-finger, where it divides into thite principal Blanches, 
 viz. 
 
 The A. Magna Pollicis, which inns along the fide of the 
 Tumb next the Fingeis, and foineiimes divides at its root, into 
 two Branches, which lupply both lides of it. 
 
 The Radialis Indicis, which runs along the fide of the 
 Fore-finget next the Thumb. 
 
 The Palmaris Profunda, which crolfes the Hand between 
 the roots of the Metacaipal Bones and Flexures of the Fingers, 
 and forms an Arcus Profundus, fi orh which Branches go off to 
 the Interoffei Mufcles and other deep parts of the Palm. 
 
 The Ulnaris appears at firft as the Continuation of the 
 Trunk of the Humeral Artery. 
 
 At its upper part, it finks deep behind the flexor Mufcles of 
 the Hand, and palfes afterwards for fome way between the Flex- 
 or Sublimis and Profundus Digitorum. 
 
 Near the Wrift, it becomes more fuperficial, and runs between 
 the Tendons of the Flexor Carpi Ulnaris and Flexor Digitorum 
 Profundus, to the Hand. 
 
 In this courfe, it lends off many Branches to the Fore-arm, 
 among which the following are the molt confiderahle. 
 
 The Recurrens Ulnaris, which runs deep among the Flex- 
 or Mufcles, and foon divides into Branches which afcend and 
 fupply the Parts about the under and inner fide of the Elbow. — 
 In the Groove behind the inner Condyle of the Os Humeri, it 
 communicates by diftinft Analtomofes with the Profunda Infe- 
 rior, or with the R,:mus Analtomoticus, lent down from the Hu- 
 meral Artery. 
 
 The Interossea Posterior, which comes off at the upper 
 end of the Interofleous Ligament, perforating it immediately at 
 its origin, and going to the back-part of the Fore-arm. 
 
 From this place, it lends upwards a Recurrent Branch, which 
 communicates, upon the back-part of the Elbow, with the other 
 Recurrent Arteries, and with the Branches lent down fiom the 
 Humeral Artery, and forms along with thefe a Plexus of Velfels 
 upon the back-part of the Joint. 
 
 The Interolfea is afterwards continued downwards, and is 
 chiefly difperfed upon the Bellies of the External Mufcles of the 
 Hand and Fingers, being commonly exhaulted before it reach the 
 Wrift. 
 
 The Interossea Anterior, which comes off femetimes 
 immediately below the former, and at other times in common 
 with it. It is ccnfiderably the larger of the two ; but only a- 
 bout half the fize of the Ulnar Artery from which it fprings. 
 
 It runs clofe upon the Interofleous Ligament, and furmlhes 
 Branches to the Mufcles and deep Parts upon the anterior fide 
 •f the Fore-arm. 
 
195 
 
 Near the VVrift, it perforates the Ligament, and goes to the Pof- 
 terior fide of the Carpus and back, of the Hand,, dividing into 
 Branches which inofculate with others of the Polteri or Inierofle- 
 ous and Rad;ai Arteries. 
 
 The Ulnary Artery, having given off its Recurrent Branch, 
 and the Arteriae Interoffese, with many Lateral Branches to the 
 inner fide of the Fore-arm, paffes by the fide of the Os Pififorme, 
 and then over the Annular Ligament into the Palm, where it 
 forms the Arcus Volaris Superficialis. 
 
 At the under end of the Fore-arm, it fends off a Dorfal Branch, 
 which psffes under the Tendon of the Flexor Carpi Uinaris to 
 the back of the Hand, where joining with Branches of the An- 
 terior Inrerolfeous and Ulnar Arteries, it affifts in forming a 
 Plexus which l'upplies the back-part of the Wrift and of the 
 Hand and Fingers with a number of Branches, which are final! 
 when compared w ; 'h thofe in the Palm. 
 
 The Arcus Volaris Sublimis, or Superficialis, is 
 placed with its convex fide downwards, and extends obliquely 
 from the root of the- Metacarpal Bone of the Little Finger to- 
 wards that of the Fit'll: Bone of the Thumb, being covered by the 
 expanlion termed Apnneurojis Palmaris. 
 
 From the Arcus Volaris, Branches are fent off in the follow- 
 ing order, viz. 
 
 Several Small Branches to the Integuments and other Superfi- 
 cial parts of the Palm : 
 
 A confiderable Branch which fir.ks near the root of the Meta- 
 carpal Bone of the Little Finger, and inofculating with the Pal- 
 mar Branch of the Radial Artery, affilts in forming the Arcus 
 Profundus : 
 
 A Branch to the inner fide of the Little Finger t 
 
 Three large Digital Branches which run oppofite to the Inter- 
 faces of the Metacarpal Bones, to the Roots of or Clefts between 
 the Fingers. 
 
 At thefe Clefts, each of the Three Digital Arteries is divided 
 into two Branches, one of which Branches of each divifion runs 
 along the Anterior Radial margin of one Finger, and the other 
 
 along the Anterior Ulnar margin of the Finger next it ; the 
 
 Three Digital Arteiies thus fupplying the margins of all tile 
 Fingers, excepting the inner margin of the Little Finger, and 
 the outer margin of the Index. 
 
 At the Roots of the Fingers, each of the Digital Arteries re- 
 ceives a finall Branch fiom the Arcus Profundus. 
 
 At the Roots and Joints, but more particularly at the Points 
 of the Fingers, the Arteries communicate by crofs Arches, and 
 fend Branches to the parts adjacent. 
 
 The Superficial Arch of the Palm commonly fends off one of 
 the Aiieiies of the Thumb, and ultimately communicates by a 
 large Anattomofes with the Root of the Arteria Magna Pollicis. 
 
196 
 
 VEINS of the SUPERIOR EXTREMITY and. of 
 PART of the NECK. 
 
 The Veins of the Superior Extremities have numerous Values , 
 and are divided into a Superficial and a Deep Set ; the former 
 lying immediately under the Integuments, the latter accompany- 
 ing the Arteries, and taking their names from them. 
 
 The Subcutaneous Veins have many large Anaftomofes with 
 each other, particularly on the Fore-arm, where they unite, fe- 
 parate, and re-unite feveral times, thus forming a Plexus by which 
 it is furrounded. 
 
 The Superficial Veins from the back of the Hand (one of 
 which, belonging to the Little Finger, was termed Salnjatella 
 by the Ancients) go chiefly to the Superficial Radial, and partly 
 alfo to the Ulnar Veins. 
 
 The Superficial Radial Veins form the Vena Cephalica , and 
 the Superficial Ulnar Veins the Vena Bafilica, at the Joint ot the 
 Elbow. 
 
 The Superficial Veins on the Anterior part of the Fore-arm 
 communicate laterally with the Radial and Ulnar Veins, and, in 
 their afeent, from a Trunk termed Mediana Longa. 
 
 The Mediana Longa, a little below the bending of the El- 
 bow, is divided into Mediana Cephalica and Mediana Bafilica, 
 which running obliquely upwards, terminate a little above the 
 Elbow, the former in the Cephalic, and the latter, eroding over 
 tile Humeral Artery, in the Bafilic Vein. 
 
 Though this defeription correfponds with the general difliibu- 
 tion of the Vt-ins of the Fore-arm ; yet, fo great is the variety 
 among them, that they are l'carcely found to agree exactly in any 
 two Subjects. 
 
 The Basilica, in its afeent, forms the principal Humeral 
 Vein, which pafl'es along the fide of the Os Humeri, a little to 
 the infide of the Humeral Artery, and receiving Branches from 
 the correfponding fide of the Arm, it runs into the Arm-pit, ancl 
 forms the Vena Axillaris. 
 
 The Cephalica afeends at the outfide of the Biceps Mufcle, 
 receives Blanches from the adjacent parts of the Arm, and com- 
 municates in levtral places with the Bafilic, and pafiing in the 
 Groove between the Large Pectoral and the Deltoid Mufcle, ter- 
 minates in the Axillary Vein. 
 
 The Deep Veins , termed alfo Vence Satellites, or Concotnites run 
 clofe by the fide of their refpeftive Arteries, one lying commonly 
 on each fide of the Artery, and receiving the Blood from the adj- 
 acent parts. 
 
 In various places they anaftomofe with each other by fliort 
 Branches, which crofi over the Arteries. 
 
197 
 
 Near the Joint of the Elbow, the Deep Radial, Ulnar, and 
 Interojfeous Veins, form a Plexus over the Bifurcation of the Hu- 
 meral Artery. 
 
 From this Plexus, a fliort but large Branch pafles outwards, 
 and forms a Communication with one of the Subcutaneous Veins, 
 and, in general, the Communication is with one of ihe Median 
 Veins. 
 
 The Vena Axillaris, formed by the Trunks of the Superficial 
 and Deep Humeral Veins, receives the Veins coi refpondmg with 
 the Circumflex Arteries, and the Internal, and the Inferior Dor- 
 fal Veins of the Scapula. 
 
 A little higher, it is joined by the Vena Thoracic# Extern a, 
 and about this place, changes its name for that of Subclavian 
 Vein. 
 
 The Vena Subclavia pafies betvven the Clavicle and firil 
 Rib, at the inner fide of the trunk of the Artery, and afterwards 
 goes over the fore-part of the Anterior Scalenus Mufcle, at the 
 under end of the Neck. 
 
 After croffing the firft Rib, it receives the Vein correfponding 
 with the Superior Dorfal Artery of the Scapula, others wh.ch foe- 
 long to the Cervical Arteries, and alfo J 'mall Veins from the Skin 
 and Mufcles on the back part of the Neck. 
 
 While fituated in the Neck, it likewife receives the External, 
 and then the Internal Jugular Veins ; and near th ^ lad a Vein of 
 confiderable fize, which correfponds with the Trunk of the Ver- 
 tebral Artery. 
 
 The Vertebral Vein communicates within the Cranium, by 
 finall branches, with the Inferior Petrofal Sinufes, or wrh Oc- 
 cipital Sinufes ; but is chiefly formed by branches arifing from 
 the Spinal Marrow and its Membrane-, and from the Bones and 
 deep-feated MufcleS of the Neck. 
 
 Behind the top of the Sternum* the Subclavian Vein frequent- 
 ly receives the Inferior Laryngeal Vein, the Anterior External 
 Jugular, and the Internal Mammary Vein. — Befides th.-le, cue 
 Left Subclavian receives alfo the Left Superior Intercjoflal Vein 5 
 after which, it goes acrofs the Root of the Great Arteries fent up 
 from the Arch of the Aorta, and joins its fellow on the oppofite 
 fide to form the Superior Cava. 
 
 BLOOD-VESSELS within the THORAX. 
 
 Of the Blood .Veflels within the Thorax, the Pulmonary Ar- 
 tery ^ and Veins, the Aorta, the Coronary Veflels, and the other 
 Veflels connected with the Heart have been already noticed. 
 Vol. II. R 2 
 
19S 
 
 The following are thofe which remain to be defcribed. 
 
 The Mammaiua Interna, which arifes from the Subcla- 
 vian, oppohte to the Inferior Laryngeal , and defeends between 
 the Pleura and Cat tiiages of the TrueRibs, at the edge of the 
 Sternum ; — fending off 
 
 A Small Reflected Branch to the Integuments and Mufcles ad- 
 jacent to the Clavicle : 
 
 One or two fmall Blanches, termed Thytnica, to the Thymus 
 Gland, and which, like the Gland itfelf, are moft eonfiderable in 
 the Young Subjeft : 
 
 A minute Branch, termed Comes Nervi Phrenici , which ac- 
 companies the Phrenic Nerve, and after giving Twigs to the 
 neighbouring Membranes, is diffributed upon the Diaphragm : 
 
 Some (mail Branches, called Mediajlince, and Pericardia, to 
 the Mediaftinum and Pericardium : 
 
 Several Branches outwards, to the Intercoftal Mufcles 5 and 
 others between the Cartilages of the TrueRibs at the edge of the 
 Sternum, to the Pe&oral Mufcles, Mamma and Integuments, 
 which communicate with thofe of the Thoracicae Externa; : 
 
 A Large Branch, at the under end of the Thorax, which is 
 difperfed upon the Diaphragm. 
 
 The Mammary Artery afterwards emerges from the Thorax, 
 commonly under the Cartilage of the feventh True Rib, and tuns 
 upon the back-part of the Reftus Abdominis Mufcle, upon the 
 upper end of which it is difperfed, after fendijig a Branch to the 
 Oblique Mufcles of the Abdomen. 
 
 The Intercostalis Superior, which comes off a little 
 farther out than the Mammary, and defending near the Spine, 
 commonly divides into two or three Branches, which fupply an 
 equal number of Intercoftal Spaces. — It alft) fends a Branch up- 
 wards to the Deep Mufcles at the under and f®re-part of 1 lie 
 Neck. 
 
 The Arteri/e BrONCHIaleS, one in the right and two or 
 three in the left fide of the Thorax, which are difperfed upon 
 the correfponding fides of the Lungs. 
 
 The Bronchialis Dextra, which arifes moft frequently 
 from the uppermoft Intercoftal Aitery of the Aorta ; and the 
 Bronchiales Sinistra, which are of unequal fize, from 
 the fore-part of the Aorta at a little diftance from each othtr. 
 
 The Bronchial Arteries fend (mail Branches to the Efophagus, 
 to the Pofterior Mediaftinum and Pericardium, and afterwards 
 accompany thofe of the Trachea through the fubftance of the 
 Lungs. 
 
 The Arteries Esophage/e, which are minute Branches 
 arifing from the Aorta, and difperfed upon the Efophagus, alfo 
 fending Twi to the Pofterior Mediaftinum. 
 
 The Intercostales Inferiores, which are nine or ten 
 pairs in number, arifing from the back-part of the Aorta, and 
 
199 
 
 running in the Grooves at the under edges of the Ribs, between 
 the External and Internal Intercoftal Mufcles. 
 
 They furnilh Branches to the Spine and Spinal Marrow, to the 
 Intercoftal Mufcles, Pleura, See. alfo numerous Branches to the 
 Mufcles on the back of the Thorax, and communicate with 
 thole of the Internal and External Mammary Arteries. 
 
 Veins. 
 
 The Blood fent to the Thorax by the Arterias Mammarise In- 
 ternae, Intercoftales, and Efophageas, is returned to the Heart by 
 the following Veins, viz. 
 
 The Mammary Intern e, which accompany their corre- 
 fponding Arteries, and terminate, the Left in the Subclavian, and 
 the Right in this, or in the top of the Vena Cava. 
 
 Some fmall Veins, as the Pericardiaco-Diaphragmatic, the 
 Thymic and Pericardiac, which, in place of joining the Mamma- 
 ry Trunk, commonly terminate, the Right in the Subclavian, or 
 top of the Cava, and the Left in the correfponding Subclavian 
 Vein. 
 
 The Venje Intercostales, which are the fame in number 
 with their Arteries, and accompany them along the edges of the 
 Ribs. 
 
 Several of the Lower Left Intercoftals unite into a trunk, 
 termed Vena Azygos, which croffes over the Spine about the mid- 
 dle of the Thorax,— behind, but fometimes before the Trunk of 
 the Aorta, — to the right fide. 
 
 The Vena Azygos, of Venafine Pari, thus originally form- 
 ed by the Lower Left Intercoftals, afeends on the fore- part of 
 the Spine over the Intercoftal Arteries, at the right fide of the 
 Aorta. •" 
 
 At its lower extremity? it generally communicates with one of 
 the Lumbar Veins, or with the Vena Renalis ; and not unfre- 
 quently with the Trunk of the Inferior Cava. 
 
 Upon the Spine, it recei ves the Right Intercojlals, and the Ripht 
 Bronchial Vein ; and turning forwards over the Root of the Great 
 Pulmonary Veflels of that fide, it terminates in the Superior 
 Cava. 
 
 The Upper Left Intercostal Veins, or fuch as are not 
 received by the Vena Azygos, terminate in a trunk on the left 
 fide, improperly called Left Vena Azygos. 
 
 The Left Vena Azygos, Left Bronchial, or Left 
 Superior Intercostal Veik, befides the Superior Intercof- 
 tal Branches, receives the Left Bronchial Veins and Branches 
 from the Efophagus and other parts near it, and terminates in the 
 Subclavian Vein. 
 
 The Vena Cava Superior, — formed by the union of the 
 Subclavian Veins, with the addition of the Vena Azygos, — paf- 
 f'es down at the right fide of the afeending Aorta, perforates the 
 
200 
 
 Pericardium, and terminates in the upper part of the Right 
 Auricle. 
 
 Blood-Vessels of /^Diaphragm. 
 
 The Diaphragm is fupplied with Blood-veflels from va- 
 rious l’ourci s, viz. thofe entering its upper part from the Inter- 
 nal Mammary, already defer bed ; alfo fmall Branches from the 
 Intercoftal and Lumbar Arteries. Its principal Branches, how- 
 ever, are the Ph tnic, 01 Diaphragmatic. 
 
 The Arteri.® Diaphragmatic^;, are two in number, one 
 on each fide, winch aril'e turn the foie part of -the Aorta as foon 
 as it enters the Abdomen. 
 
 In general, their oiigin is diftir.fl from each other, but fome- 
 times by a common Trunk; and now and then, one or both, 
 originate from the root of the Ccehaca. 
 
 They' aftei wards go obi quely upwards and outwards over the 
 Crura of the Diaphragm, fpread out into many Branches 
 which are chiefly difperfed upon its Flefhy lides, and inofculate 
 with thole which enter at its upper fui face. 
 
 They likewife give fmall Branches to t lie Glandulse Renales, to 
 the Cardia, and parts in general which lie near them. 
 
 The VENiE Diaphragmatic^;, like their correfpomling 
 Arter.es, run upon .he under part of the Diaphragm, and termi . 
 nate in the Inferior Cava, behind the Liver,— the right being 
 commonly a little lower than the left. 
 
 BLOOD-VESSELS of the CHYLOPOETIC, and 
 ASSISTANT CHYLOPOETIC VISCERA. 
 
 Arteries. 
 
 The Arteries of thefe Vifcera, conlift of the Caeliac , and the 
 Superior and Inferior Mcfenterics ; ail of which ai e Azjgous or 
 fingle Arteries afifing from the fore part of the Aorta. 
 
 Arteria Coeliaca. 
 
 The Arteria Coeliaca, arifts from the Aorta, immedi- 
 ately after it erht-iges from between the Crura of the Diaphragm 
 into the Abdomen ; and is ftuated at the upper edge of lue Pan- 
 creas. 
 
 The Trunk of the Coeliac Artery is remaikably fliort, being 
 little more than half an inch in length, before it divides into its 
 three prine pai Branches, called from their deftination, Superior 
 Gajh ic, Hepatic, and Splenic. 
 
201 
 
 The Gastrica Superior, or Coronaria Ventriculi 
 Superior, is the fmalleft of the three. It goes upwards, and 
 a little towards the left, to reach the right fide of the upper Ori- 
 fice cf the Stomach. 
 
 Here it fends Branches to the Cardia, which encircle it, and 
 afcending fomeway upon the Efophagus, communicate with the 
 Arteriae Efophageae. 
 
 The Trunk of the Artery afterwards divides upon the fmall 
 Curvature of the Stomach, into principal Branches, fome of 
 which run acrofs the upper and under Surfaces, and others ob- 
 liquely towards the right fide; fupplying a large portion of the 
 Stomach, and fending Twigs to the Omentum Minus, — while 
 the Trunk is frequently extended as far as the Pylorus. 
 
 The Arteria Hepatica, the largeft of the three, pafi'es ob- 
 liquely upwards, towards the Pylorus, — before, and a litttle to 
 the right tide cf the Lob-ulus Spigelii, — till it arrives at the Ca- 
 vity of the Liver called Porta. 
 
 Where it approaches the Porta, it divides into the Gaftroica- 
 Inferior Dextra, and the Proper Hepatic Artery. 
 
 The Gastrica Dextra, or Gastrica Inferior Dex- 
 tra, or Gastro-Epiploica Dextra, feuds out — 
 
 The Arteria Pylorica. which, however, is frequently produced 
 immediately from the Hepatic Artery. It gives Branches to the 
 Pylorus and other parts about t:ie final! end of the Stomach, and 
 afterwards runs fome way along its fmail Curvature, incfcuia- 
 ting with the Sjpetior Gaftric Artery. 
 
 Befides this principal Branch, there are a few fmailer ones fent 
 from the Gaftrica Inferior to the Pylorus. 
 
 The Duodenalis, whjch is difperled upon the beginning and 
 right portion of the Duodenum, along with other Branches com- 
 ing from the fame fource, but of inferior fize. 
 
 Rami Pancreatici, diftributed to the right end of the Pan- 
 creas. 
 
 After furnifiiing the Branches already mentioned, the Inferi- 
 or Gaftric Artery paffes under the Pylorus to the great Curva- 
 ture of the Stomach, along which it runs; being include.!, to 
 near its large extremity, in the Layers of the Anterior Portion of 
 the Omentum. 
 
 In this courfe, it fends off— 
 
 The Rami Epiploici, which are long and /lender Branches dif- 
 perfed upon the Epiploon or Omentum. 
 
 The Rami Gajirici, which plun ing fuddenly into both fides 
 of the Stomach, communicate with the Pyloric and Superior 
 Gaftric Arteries. 
 
 The Hepatic Artery, having given out the Inferior Gaftric, 
 and frequently, the Pyloric Artery, foon divides into two prin- 
 cipal Branches, a right and left, of unequal fize, which ruu 
 
202 
 
 into the Porta the one,— tinder the Hepatic Du£t,— to fupply 
 the great, aad the other the final 1 Lobe of the Liver. 
 
 From the Right Branch, before it plunges into the Liver, is 
 fent off the rirteria Cyflica afterwards dividing into two /m iller 
 Branches, termed GemelU, which are difperfed upon the Gall- 
 bladder. 
 
 Frequently, befides the Hepatic Artery fent of from the Coe- 
 ] i ac, there is another, corning fomesimes fr,.m the Superior 
 Gaftr'c, at other times from the Superior Mefenteric Ateiy, to 
 be lent into the Liver. In fuch cafes, the Trunk which gives 
 origin to this additional Arteiy is greater than ufual, and.th« 
 Hepatic Branch which it a companies is proportionally imaller. 
 
 The Ar.ter.ia Splenica, nearly equal in fize to the Trunk 
 of the Hepatica, takes a long and ferpentine courfe acrofs t he 
 left fide of the Body ; running firlt behind, then at the tipper 
 part of the Pancreas in its way to the Spleen. Its Blanches 
 are, 
 
 The Rami Pancreatici, which are few in number and fmail. 
 They run from the Splenic Artery nearly at right angels, and 
 fupply the greater part of the Pancreas. 
 
 The Gaftrica Sinifra, Gaflrica Inferior Sinifra, or Gaflro - 
 Epiploica Sinifra , which is conliderably inferior in length and 
 fize to the Gaftrica Dextrit. It communicates by its Brandies 
 with the Gaftrica Superior, and Inferior, while its Trunk runs a 
 little way towards the right fide along the great Curvature of the 
 Stomach. 
 
 It fends feme Rami Pancreatici, and Gaflro -Epiploici, and 
 Mefo-colici Siniftri, to the Pancreas, left; portions of the Omen- 
 tum and Mefocolon ; while its Tiunk frequently forms a com- 
 mon Arch with the Gaftrica Dextra. 
 
 Three or four confiderab e Branches, termed Eafa Previa, or 
 drterice Breves, which run to the left pari of the great Curva- 
 ture of the Stomach, to be diltributed upon its large extremity ; 
 their Ramifications anaftomuling with thofe of the Superior and 
 of the Left Inferior Gaftric Arteries. 
 
 The Rami Splenici, feveral in number and of confiderable 
 fize, which go at the concave fide of the Spleen, to be diftributed 
 throughout the whole of its fubftance. 
 
 Mesenter.ica Superior. 
 
 The Mesenterica Superior arifes from the Aorta, im- 
 mediately below the Cceliac Artery, which it equals in fize ; and 
 running under the Pancreas, and then over the Duodenum, it 
 palfes between the Layers of the Mefentery towards the under 
 fide of the Abdomen. 
 
 In its defeent, it is bent a little to the left fide, its lower ex- 
 tremity nuning towards the beginning of the Colon. 
 
 From the conyex fide of the Artery, many large Branches are - 
 fent off to thefmall Inteftines ; while others proceed in the oppo- 
 fite direftion to the right fide of the Colon. 
 
203 
 
 The FirJ} Arteries Tent off from the Trunk are very inconfide- 
 rabie, running to the Pancieas and to the left portion of the Du- 
 odenu ii, and commun casing there with Branches of the Coeliac 
 Aitery. 
 
 The principal Branches from the left ftde of the Trunk are 
 difpetfed upon the Jejunum and Ilium, fupplying, in t heir courfe, 
 the Layers of the Mefcntcry with the parts it contains. 
 
 The firft of thefe Branches are (hurt and fmail, thole which 
 fucceed gradually increafe in length and lize to the middle of the 
 Arch, after which they dimimlh aga n fo ewhat in the fame pro- 
 portion towards the lower part of the Ilium. 
 
 In their courfe through tne Mefentery, .he principal Branch- 
 es communicate, full by reciprocal Arches, then by Areolae of 
 different figures, which inereafe in number, but diminifh in fize 
 as they approach the Inteftines. 
 
 From thefe Areolae, many Branches are detached, which take 
 a ftraight courfe to the Inteftines, and are afterwards ramified 
 through their fubftance, forming numbsrlefs Analfomofes with 
 each other. 
 
 The Branches produced from the right or concave fide of the 
 Trunk are iituaied between the Layers of the Melo-colon, — 
 their length being almoft equal to the breadth of that Membrane. 
 
 Near the Inteftines, they communicate by large and then by 
 fmaller Arches : Thefe laft, however, are lefs frequent than thofe 
 which belong to the fmail Inteftines. 
 
 The principal Branches are the following: — 
 
 The lleo-colica, which arifes near the tinder part of the Trunk, 
 fupplies the end of the Ilium and beginning of the Colon, and 
 communicates with the Branches lent from the extremity of the 
 Trunk of the Artery. 
 
 A Short Trunk, which divides into— 
 
 The Colica Dextra, for fupplying the right fide of the Colon, 
 —its Branches communicating with thofe of the lleo-colica : And 
 
 The Colica-Media, or Media Anajlomotica, which proceeds to 
 the great Aich of the Colon. 
 
 Near the Colon, the Colica Media divides into two large 
 Branches ; one forming an Ar. h with the Dextra, the other with 
 a Branch of the Mefenterica Inferior. 
 
 From the oppofue fi le of the Colon, Branches of this Artery 
 run to the Omentum, and communicate with the Gaftro-Epipioic 
 Arteries. 
 
 Befides the Colic Branches already deferibed, there is frequent- 
 ly an additional one, which arifes from the beginning of the Su- 
 perior Mefenteric Artery, and in its afeent fplits into two others, 
 one of which, uniting whh ehe Colica Media, forms the large 
 Mefocolic Arch, and the other a fimilar Arch with the afeending 
 Branch of the Inferior Mefenteric Artery. 
 
204 
 
 Mesenterica Inferior. 
 
 The Mesenterica Inferior arifes from the Aorta fome- 
 ■what lower than half way between the Superior Mefenteric and 
 the Bifurcation of the Aorta. 
 
 It defcends obliquely upon the left Pfoas Mufcle, and foon 
 divides into principal Branches. 
 
 Thefe near the Inteftine join with each other, and form Arches, 
 from which others go off compoling Areolae in fomefmeafure fi- 
 milar to thofe which belong to the right fide of the Colon. — The 
 principal Branches are : — 
 
 The Ramus Afcendens , which divides near the Intelline, into 
 two Branches ; one of which joins the Colica Media, to form 
 the great Mefocoiic Arch, the other is reflefled upon the left 
 portion of the Colon. 
 
 The Colica Siniftra, which is frequently double from its ori- 
 gin, or at other times lplitting intwo two Branches, one joining 
 the Ramus Afcendens, the other palling down by the Sigmoid 
 Flexure of the Colon. 
 
 The Hemorrhoidalis Interna , which is the Trunk continued. 
 It anaftomoles with the Colica Siniftra, and afterwards defcends 
 upon the back-part of the Reftum to near its under extremity. 
 
 Veins. 
 
 The Veins which return the Blood from the Chylopoetic and 
 Affiftant Chylopoetic Vifcera, accompany their refpeffive Arte- 
 ries,— the Hepatic Branch excepted. — They have, like their Ar- 
 teries, large and frequent Communications with each other, are 
 much fuperior in fize, and, as well as the other Veins of the Vil- 
 cera fituated in the great Cavities, are deftitute of Valves. 
 
 The following are the Principal Trunks. 
 
 The Mesenterica, or Mesaraica Minor, or II/c- 
 
 MORRKOIDALIS INTERNA. 
 
 The Mesenterica Minor, running up at the left fide of 
 the Spine, receives— 
 
 The Proper Vena Hemorrhoidalis Interna, which 
 returns the Blood from the Inteftinum Reftum ; — the name ob- 
 tained from the Vein being fuppofed to be connected with the 
 Tumours called Hemorrhoids or Piles. 
 
 The Vena Colica Siniftra, which return the Blood from the 
 left portion or fide of the Colon. 
 
 A Vena Duodenalis, which returns the Blood from the left 
 portion of the Duodenum. 
 
 The Mefenteiica Minor commonly terminates in the Vena 
 Splenica, though not unfrequently in the Mefenteriea Superior. 
 
 Vena Splenica. — The Vena Splenica, fituated at the under 
 fide of its Artery and immediately behind the Pancreas, re- 
 ceives— 
 
205 
 
 The Rami Splenici, which return the Blood from the Spleen : 
 The Rami Pancreatici, which pafs from the under end of the 
 Pancreas : 
 
 The Vena Breves, or Vafta Bre-via, which come from the left 
 or great end of the Stomach : 
 
 The Vena Gaftrica Siniftra, or Epiploica SiniBra, which comes 
 from part of, the great Arch of the Stomach, and correfponding 
 portion of the Omentum : 
 
 The Gaftrica Superior, which comes from the fmall Curva- 
 ture of the Stomach and Omentum Minus, and goes into the 
 Splenic near its termination, or into the beginning of the Vena 
 Portae. . . 
 
 The Splenic and Inferior Mefenteric Veins, after receiving 
 their refpeftive Branches, form a lhort Trunk which joins the 
 Superior Mefenteric. 
 
 Vena Me s enteric a Superior, or Major. The Great 
 Mefenteric Veiif, fituated at the under fide of the Artery, re- 
 ceives — s 
 
 The Rami Mefenterici, which are very large and numerous, re- 
 turning the Blood from the Jejunum and Ilium, — the Branches 
 going into the left fide of the general Trunk. 
 
 The lleo-Colica, which comes from the end of the Ilium and 
 beginning of the Colon. 
 
 The Colica Dextra, which belongs to the right fide of the Co. 
 Ion, and terminates in the right or concave fide of the Mefenteric 
 Trunk. 
 
 The Colica Media Anaftomotica, which comes from the right 
 portion of the Great Arch of the Colon, forming, with the de- 
 fcending Branch of the Mefenterica Minor, a large Arch fimilar 
 to that of the correfponding Artery, and terminating alfo in the 
 right fide of the Trunk. 
 
 The Gaftro - Epiploica Dextra, which belongs to the right por- 
 tions of the Stomach and Omentum, and frequently unites with 
 the Veins from the fide of the Colon, forming a fhort common 
 Trunk, which has the term of Gaftro-Colica applied to it. 
 
 The Pylorica and Duodenalis, which fometimes terminate 
 in the Superior Mefenteric, at othertimes in the Gaftrica Dextra. 
 
 The Great Mefenteric Vein, formed by the Branches mention- 
 el above, paffes over the beginning of the correfponding Artery, 
 and joins the Vena Splenica. 
 
 The Trunk formed by thefe Veins, runs under the' head of 
 the Pancreas, and here obtains the name of Vena. Port ee, or V. 
 Portarufn. 
 
 Vena Port/e. 
 
 The Vena Port.s, formed by the two Mefenteries, and by 
 the Splenic Vein, returns the Blood from the Stomach and Intef- 
 tines, and from the Spleen, Pancreas, and Omenta, 
 
 Vol. II. S 
 
206 
 
 The under part of the Vena Portae is termed by fome Authors 
 Vena Porta’ Abdominalis, or Vent rails ; while the upper part, — 
 being- of great fize, but without having any particular Dilatation 
 in it, — is called Sinus of the Vena Portae. 
 
 The Vena Portae, a f its beginning, frequently receives the Ve- 
 r.a Gaftrica Dextra, the Gaftrica Superior, the Pylorica, and the 
 Duodenalis, which at oilier times terminate in one of the great 
 Trunks which form it. 
 
 It pafies upwards, inclining a little to the right in its courfe to 
 the Liver, having the Trunks of the Biliary Duffs before, and 
 the Hepatic Artery on the left fide of it, — and is about three or 
 four inches in length. 
 
 When it reaches the Porta of the Liver, it receives the Venae 
 Cyfticae into its Trunk, or into its right divifion, either by two 
 feparate Branches, or tiiefe united into a fmgle Vein. 
 
 In the Porta, it divides into two great Branches, a right and 
 left, fometimes termed Vena Porta Hepatica, which go off nearly 
 at right angles, to be difpcrl’ed, through the fubffance of the li- 
 ver, after the manner of an Artery, the fuborclinate Branches ac- 
 companying thofe of the A. Hepatica. 
 
 From the extremities of the Vena Portarum, and likewile from 
 the extremities of the Hepatic Artery, a fet of Veins arife, term- 
 ed Vena Hepatica, and fometimes Vena Cava Iiepatica, which 
 accompany the Branches of the Hepatic Arteiy and Vena Por- 
 tarum. 
 
 The Branches of the Veil* Hepaticas afterwards unite into 
 large Trunks, which recede from the Hepatic Artery and Vena 
 Portae, and terminate in the Inferior Cava. 
 
 Their termination in the Cava is by two, and frequently by 
 three Trunks, at the place where it perforates the Diaphragm ; 
 but commonly, below this, a few final 1 Hepatic Branches-go into 
 the Cava where it is fituated behind the Liver. 
 
 BLOOD-VESSELS of the OPvGANS of URINE and 
 GENERATION. 
 
 Arteria Renalis. The Arteria Renalis, called alfo A. 
 Emulgens, arifes from the fide of the Aorta, a little below the root 
 ©f the Superior Mefenteric Artery. 
 
 It commonly comes off by one large Trunk, though frequent- 
 ly by two or more, in which cafe, each of thefe is 1'maUer than 
 when the Artery is fingle. 
 
 It runs acrofs the Spine and Pfoas Mufcle, nearly in a tranf- 
 *c,fe direction. The Artery of the right fide goes behind the 
 
207 
 
 Vena Cava, and is longer than the left, in confeqnence of the 
 Cava being fuuated between the Aorta and the Right Kidney. 
 
 At the concave edge of the Kidney, the Artery divides into 
 three or four Branches, which fometimes fend Twigs to the 
 GlandulaRenslis and Tunica Adipcfa of the Kidney. 
 
 Ti;e Renal Branches then plunge into the l'ubftahce of the Kid- 
 ney, furround its Pelvis, and afterwards ramify chiefly in its 
 Conical Subftance ; — forming Arches with each other, but few 
 in number, at the roots of the Papillae. 
 
 The Vena RenaHS, or Emulgens, terminates in the In- 
 ferior Cava; and is more fuperncial than its correfponding Arte- 
 ry. It is the largelf Vein received by the Cava from its origin 
 to the part where it reaches the Liver. 
 
 The left Renal Vein- is the longer of the two ; — the Aorta, be- 
 fore which it paffes, being lltuated between the Cava and Left 
 Kidney. 
 
 Arteri* Capsularss. The Arteriae Capfulares, or Ar- 
 teries of the Renal Gap Jules or Glands, are final 1 but numerous. 
 
 They are derived from the Renal and Diaphragmatic Arteries ; 
 and, in general, the left Renal Gland receives additional 
 Branches from the Trunk of the Aorta. 
 
 The Ven^e Capsulaues commonly unite into a largeTrunk, 
 which, in the left fide, terminates in that of the Kidney, while 
 in the right it frequently goes into the Cava. 
 
 Arteri/E Adipose. The Arteres which Amply the Tu- 
 nica Adipofa of the Kidney are numerous Twigs proceeding 
 from the Diaphragmatic, Capfular, and Renal Arteries, or frora 
 others near it. 
 
 The Veins which return from the extremities of thefe Arteries 
 pafs into the Trunks adjacent. 
 
 Arteria S-permatiCA. The Spermatic Artery, the diame- 
 ter of which iifmall when compared with its great lengih, arifes 
 oppolite to it* fellow, from the fore-part -of the Aorta, a little 
 below the Renal Arteries. 
 
 Sometimes it anfes from the A. Renalis, at other times a little 
 higher from the Aorta, and in rarer inftances from the Diaphrag- 
 matic Artery. 
 
 It delcends, in a waving direction, on the furface of the Pfoas 
 Mufcle, covered by the Peritoneum ; the right palling obliquely 
 over the Cava, the left behind the Colic Arteries of the fame 
 fide, and both before the Ureters to the under part of the Abdo- 
 men. 
 
 After this, it perforates the R'ng of the Obliquus Externus r 
 and runs in the Spermatic Cord, where it divides into Branches 
 which are difperfed in a very convoluted manner upon the Telticle 
 and Epididymis. 
 
 In the defeent of the Artery it imparts — 
 
 livigs to the Tunica Adipofa of the Kidney. 
 
 To the Peritoneum and"Ce!iular Subftance near it;— and 
 
20S 
 
 To the Ureters, — which are alfo fupplied with other Arteries 
 from the adjacent. Vefiels, viz. from the Rena] and Capfular Ar- 
 teries, from the Aorta, the Iliacae_and Veilcales. 
 
 The Ven a Spe RM atic a is much larger than its correfpon- 
 ding Artery, and is furnifhed with Valves within, but more par- 
 ticularly without the Abdomen. 
 
 It forms a Plexus which accompanies the Artery, and about 
 the place where it recedes from it, which is nearly oppofite the 
 under end of the Kidney, it forms a fingle Trunk, which in the 
 right fide goes into the Cava a little below the Emulgent Vein, 
 and in the left into the correfponding Vena Renalis. 
 
 Beiides the Artery commonly termed Spermatic, the Tefticle 
 generally receives a Minute Branch, which arifesfrom the Hypo- 
 gaftric, and accompanies the Vas Deferens to the Body of the 
 Tefticle upon which it is difperfed, — communicating there with 
 the Branches of the Spermatic Artery. 
 
 The Vein proper to this Artery, terminates in the Vena Hypo- 
 gaftrica. 
 
 The Spermatic Artery, in the Female, has the fame kind of 
 Origin, and the fame courfe through the Abdomen as in the 
 Male but in place of perforating the Abdominal Ring, as it 
 does in the latter, it defcends into the Pelvis, between the Lamina 
 of the Ligamentum Latum, to be difperfed firft upon the Ova- 
 rium and Uterine Tube, and then upon the Body of the Uterus 
 itfelf, — pafling in at its corner, and communicating with the Ar- 
 tery of the oppofite fide. 
 
 The Spermatic Vein has the fame termination in the Female as 
 in the Male, — but is confiderably larger. 
 
 Arteri^ IliaCjE. The Iliac Arteries confift of the T<wo 
 Common lliacs, which are formed by the Bifurcation of the Aor- 
 ta ; and of the External and Internal lliacs of each fide, which 
 are formed by the Bifurcation of the Iliacas Communes. 
 
 The External Iliac paffes out of the Abdomen behind the Li- 
 gament of I'oupart ; the Internal, termed alfo A. HypogaJIrica, 
 defcends obliquely into the Pelvis. 
 
 At tjie fide of the Pelvis, the Internal divides into many 
 Branches, feme of which belong to the Organs of Urine and Ge- 
 neiation, the reft to other parts of tk^Pelvis and adjacent parts 
 of the Thigh. 
 
 The following are the Branches lent from the Hypogaftric Ar- 
 tery to the Organs of Urine and Generation. 
 
 Arteria Umbilicalis. The Arteria Umbilicalis appears 
 in the Foetus, as the continued Trunk of the IptotnaL Iliac ; but 
 in the Adult, is fliri veiled in the form cf a Ligament, excepting 
 at its beginning or under part. 
 
 The beginning of the Umbilical Artery gives off — 
 
 One or more Arteries Vejicales, which run to the ru der part of 
 the Bladder, and extend along its Tides as far as the Fundus Ve- 
 
209 
 
 ficae. At their origin, they furnifh Twigs to the Veficulae Semi- 
 i.ales, Proftate Gland, and Reftum. 
 
 In the Female, the Umbilical Artery fends minute Branches to 
 the Uterus and Vagina. 
 
 Arteria Uterina. The Arteria Uterina, termed alfo Ute- 
 rina Hypogajlrica, is much larger than the Spermatic Artery. 
 
 It arifes from the Hypogaftric, near the origin of the A. Pu- 
 dica, and runs into the Uterus at its under extremity. 
 
 It is afterwards reflefted upwards along the edge of the Uterus, 
 towards its Fundus or upper part, where it meets with the Sper- 
 matic Artery, with which it forms frequent Anaftomoles, and 
 afterwards many Communications with the Uterine Artery of 
 the oppofite fide. 
 
 The Uterine Artery fends Branches downwards to the fub- 
 ftance of the Vagina, and others forwards to be dil'perfed upon 
 the Bladder. 
 
 Arteria Vaginalis. The Arteria Vaginalis is frequently 
 awanting.— When prefent, it arifes from foine of the Branches 
 of the Hypogaftric,— as that common to the Ifchi die and Pu- 
 dic, — or from the Haemorrhoidalis Media j and is diftributed 
 upon the under part of the Vagina. 
 
 Befides this, there are other Vaginal Branches from the neigh- 
 bouring Arteries ; as from the Veficales , Uterina , and Pudica, 
 which communicate with each other, and with the proper Vagina- 
 lis, upon the fubftance of the Vagina. 
 
 Arteria Pudica, or Pudenda Communis. — The Arte- 
 ria Pudica, named from its belonging to the Parts of Generation 
 in both fexes, comes off either immediately from the Trunk of 
 the Hypogaftric, or from the A. Ilchiatica. 
 
 ' It palfes out of the Pelvis, through the under part of the 
 Notch of the Os Ilium, at the lower edge of the Pyriform Muf- 
 cle. 
 
 It then turns between the Sacro-fciatic Ligaments, to get to 
 the inner fide of the Tuber Ifchii, where it is lodged deep in the 
 Cellular Subftance. 
 
 From the Tuber, it proceeds along the inner fide of the Crus 
 of the Os Ifchium and of the Os Pubis, and behind the Crus of 
 the'Penis, till it approaches the Symphyfis of thePubis. 
 
 In it s courfe, it fends off many Branches, of which the follow- 
 ing are the principal, viz. — 
 
 Branches to the Veficulae Seminaies, Proftate Gland, Neck of 
 the Bladder, andRe£tum. 
 
 _ Branches to the Mufcles and parts adjacent to the Sacro fcia- 
 t ’ c ^jg aments 5 fome of them extending as far as the Joint of 
 the Thigh-bone. 
 
 Branches to the Mufcles, Membranes, and Fat about the Tu- 
 ber of the Os Ifchium. 
 
 Vol. II. S 2 
 
210 
 
 The Arteria Hamorrhoidalis Externa, which foon divides into 
 Branches, to fupply the Mufcles and Integuments about the 
 verge of the Anus. 
 
 The A. Perinei , which paffes under the Tranfverfalis Perinci 
 Mufcle, in the fuace between the Crus of the Penis and Bulb of 
 the Urethra, and gives Branches to the Skin and Mufcles aftbe. 
 fore-part of the Anus and root of the Penis, and to the Scro- 
 tum ; while the Artery itfelf terminates on the under tide of the 
 Penis. 
 
 After difperfing the Branches already mentioned, the Pudic 
 Artery divides, at the root of the Penis, into three principal 
 Branches, viz. — 
 
 The Firji Branch , which paffes into the Bulb of the Urethra, 
 and is continued forwards in the Corpus Spongiofum Urethrae, 
 into ;he Cells of which many of its Branches open. 
 
 The Second Bi anch, termed Profunda Penis, which goes into 
 the Crus Penis, anddirefls its courfe in the Corpus Cnvernofum ; 
 its Branches communicating with the Artery of the oppofrte fide, 
 and with the Cells of the Penis. 
 
 The Third Branch, called DorfaUs Penis, which turns be- 
 tween the Symphyfis of the Pubis and root of the Penis, and pro- 
 ceeds along the Dorfum, as far as the Gians, adhering clolely 
 to the L’gamentous Subftance which inclofes the Corpora Caver- 
 nofa, and fending Branches to it and to the Integuments. 
 
 In the Female, the Pudic Artery has the fame general courfe as 
 in the Male. 
 
 After reaching the inner fide of the Tuber of the Os Ifchium, 
 it is extended forwards, and fends Branches to the Anus, Peri- 
 neum, end of the Vagina, and Labia Externa, and terminates in 
 the Clitoris, tbmewhat in afimilar manner as in the Penis. 
 
 The Blood is returned from the Branches of the Hypogaftt ic 
 Artery difperfed upon the Organs ol Urine and Generation, by 
 the following Veins, viz.— 
 
 The Vena Veficalis, which returns the Blood from the Bladder., 
 
 The Vena Uteri): a Hypogajirica , which comes from the Uterus. 
 
 The Vena Magna lpjius Penis, which tuns along the middle 
 of the Dorfum, and is often double to near the root of the Pe- 
 nis ; after which it paffes between this and the Arch of the Pu- 
 bes, forming a Plexus which furrounds the Neck of the Bladder, 
 and fending out Branches which terminate in others at the frdes 
 of this Vifcus. 
 
 The Vena Pudica, which communicates anteriorly with the 
 Branches of the Vena Magna at the root of the Penis, and after- 
 wards paffes back with the correfponding Artery. 
 
 The Vena Eegtnentorum Penis, which is formed by fmall Sub- 
 cutaneous Branches, and ends in the top of the Femoral Vein. 
 
 The Veins above-mentioned, the 1 a if excepted, terminate in the 
 Hypogafhica, along with other Veins belonging to the Pelvis, to 
 be afterwards deferibed. 
 
211 
 
 BLOOD-VESSELS of the CONTAINING PARTS of 
 THE ABDOMEN, AND OF THE PELVIS AND 
 INFERIOR EXTREMITY. 
 
 Arteria: Lumeares. — The Lumbar Arteries, which are 
 commonly four in number on each fide, arife in pairs from the 
 back-part of the Abdominal Aorta, in the fame manner as the In- 
 tercoftals do from the Aorta in the Thorax. 
 
 They run fir ft over the fore-part of the Bodies of the four up- 
 permolt Lumha-r Vertebraae, and afterwards go between them and 
 the Pfoae Mufcles, in their way towards the fides of the Abdo- 
 men. 
 
 They give Branches to the Spine, to the Spinal Marrow and 
 Its '^vdembrhnes ; are particularly difperfed upon the Lumbar 
 Mufcles, and upon "{he ; Tranfverfus and Obliqui Abdominis; 
 and perforating thefe, they alfo furnilh Branches to the large 
 Mufcles and the Integuments in the back-part of the Loins. 
 
 Superiorly, they communicate with the lower Intercoftal and 
 Diaphragmatic Arteries. 
 
 Sacra Media. The Sacra Media is a fmall Azygos Ar- 
 tery, which aril’es from the under and back-part of the Aorta, 
 immediately at its Bifurcation. 
 
 It generally' fends off a Branch over each fide of the laftYer- 
 tebra of the Loins, which takes nearly the fame courl’e back- 
 wards with the Arterise Lurhbares. 
 
 The Sacral Artery afterwards defeends along the middle of 
 the Sacrum, as far as the Os Ccccygis, fending Branches to the 
 Membranes and Subftance of thefe Bones, and to the back part 
 of theReftum. 
 
 Iliac.® Communes. After, giving off the Arteries of the 
 Contents and of the containing parts of the Abdomen, the 
 Aorta, upon the under part of the Fourth Lumbar Vertebra, 
 divides into the Two Common Iliac Arteiies, which are of equal 
 fize. 
 
 They pafs obliquely downwards and outwards ; and at the un- 
 der and lateral parts of the laft Vertebra of the Loins, i. e. oppo- 
 nte to the polterior Symphylas of the Pelvis, each divides into 
 two others, an Anterior, termed Iliaca Extenia, and a Pofterior, 
 termed Iliaca Interna, or Hypogaftrica. 
 
 Iliaca Externa. The Iliaca Externa, which appears in 
 the Adult as the continuation of the common Trunk, delcends 
 along the Brim of the Pelvis, taking a curved dire&ioifby the 
 lide of the Pfoas Mufcle, and afterwards paffes behind the Liga- 
 ment of Poupart, to form the Femoral Artery. 
 
 In this couife, it does not fend off any Branches, excepting 
 fometimes a Twig or two to the Peritoneum, Pfoas Mufcle, &c. 
 
212 
 
 till it is about to leave the Abdomen, where it gives rife to two 
 principal Arteries, — the Epigajfrica, and Circumflexa OJJis IHi. 
 
 The Arteria Epigastrica, obtaining its name from its 
 fituation in the fore-part of the Belly, goes off from the inner 
 fide of the Femoral Artery, immediately before that Velfel gets 
 behind the Ligament of Poupart. 
 
 At its origin, it is a little bent downwards, and about half an 
 inch from the place where it firft comes off, it crofles obliquely 
 upwards and inwards, behind the Spermatic Cord in the Male, 
 and round Ligament in the Female. 
 
 It proceeds in this oblique manner behind the Tendon of the 
 Tranfverfus, till it reaches as high as the point of the Pyramida- 
 lis, after which it takes a perpendicular direflion along the back- 
 part of the Rectus Abdominis Mufcle. 
 
 It furnilhes Branches to the Mufcles, Integuments,. and Mem- 
 branes of the fore-part of the Abdomen, communicates in feve- 
 ral places with the Lumbar Arteries, and terminates a little above 
 the Umbilicus, where it foims feveral diftinft though fmall 
 Anaftomofes with the under end of the Mammaria Interna. 
 
 Circumflexa Ossis Ilii. — The CircumP»ex Artery of the 
 Ilium, almoft as large as theEpigaftric Artery, ariles nearly op- 
 pofite to it, though frequeutly a little lower, — immediately be- 
 hind the under end of the Fallopian Ligament. 
 
 It runs at the under edge of the Os Ilium, till it arrives near 
 the Vertebrate of the Loins. 
 
 It gives Branches to the Pfoas and Iliac Mufcles, to the under 
 end of the Obliqui and Tranfverfus Abdominis, and at length 
 communicites with the Epigaftric, and with the Inferior Arte- 
 ries of the Loins. 
 
 Iliaca Interna. The Uiaca Interna, or Hypogaftrica' 
 palfes downwards and backwards in the pofterior and lateral part 
 of the Cavity of the Pelvis, for about a couple of Fingers- 
 breadth, after which it generally divides into a Pofterior and An- 
 terior Set of Branches ; the former fupplying the parts neareft the 
 Sacrum and Ilium, the latter belonging more immediately to the 
 parts about the Anterior region of the Pelvis. 
 
 Posterior Branches. 
 
 Imo-L umbar is, or 1 1 1 a c a Interna Mitjor. The Ileo- 
 lumbar is a fmall Artery, arifing fometimes from the end of the 
 Hypogaftric, at other times from the beginning of the Glutea. 
 
 It palfes outwards under the Pfoas Mufcle, and divides fud- 
 denly into Blanches, one of which frequently forms a kind of 
 Lumbalis Ima. 
 
 The other Blanches go to the Pfoas, and Iliacus Internus 
 Mufcles, communicating there wiih the Lumbar Arteries and 
 Circumflex Branches of the Ilium; — a particular Twigconftitu- 
 ting an A. Nutritia, or Medallaris of the Os Ilium. 
 
21.3 
 
 SacR/e Laterales. Thefe are generally two or three in 
 number, arifing from the common Trunk, or frequently from 
 the Gluteal Artery ; — though fometimes, there is only a fingle 
 Artery, which defcends by the fides of the Sacral Holes, giving 
 Branches, which fupply the place of the Sacrae Laterales, and 
 fometimes alfo of the Sacra Media. 
 
 They furnifh Branches to the Membranes on the fur face of the 
 Os Sacrum, and inofculate by crofs Twigs with the Sacra Me- 
 dia. 
 
 Their principal Trunks enter the Anterior Sacral Holes, to 
 be diftributed upon the Cauda Equina and the Membranes and 
 Bones inclofing it. 
 
 Arteri a Glut ea. — This is fometimes termed Iliaca Po- 
 Jierior, and is the lsrgeft Branch of the Hypogaftnc Artery. 
 
 Soon after it arifes, it pafies through the upper part of the 
 great Notch of the Os Ilium, and is refle&ed over the edge of the 
 Bone, in the manner of the Inferior Scapulary Artery. 
 
 At the under edge of the Gluteus Medius, it is divided into 
 two fets of Branches, one of which runs in a radiated direction 
 clofe upon the Bone, and is chiefly difperfed upon the two fmaller 
 Glutei, while Branches of inferior fize run fome of them down- 
 wards to the Mufcles and Ligaments about the Joint of the 
 Thigh, and others backwards to the parts about the Sacrum, 
 communicating with the Lateral Sacral Arteries through the Po- 
 fterior Foramina of the Os Sacrum. 
 
 The other fct of Branches of the Gluteal Artery creeps in be- 
 tween the Gluteous Medius and Maximus Mufcles, upon the 
 latter of which it is chiefly difperfed. 
 
 Anterior Branches. 
 
 Arteria Obturatoria, or Oeturatrix.— ' The Obturator 
 Artery has its origin from the Trunk of the Hvpogaftric, or 
 from the Ileo-lumbar or from the Ifchiatic, and fometimes from 
 the end of the Iliaca Externa. 
 
 It defcends in the Pelvis by the fide cf the Pfoas Mufcle, and 
 afterwards pafles through the Hole at the upper part of the Ob- 
 turator Ligament. 
 
 While in the Pelvis, it frequently gives Twigs to the Bladder 
 and other parts near it. 
 
 After perforating the Ligament, it divides into Branches, one 
 fet of which are difperfed upon the parts about the Hip-joint, 
 while another belong to the Obturator Mufcle, and to the Muf- 
 cles which are fituated at the upper and inner part of the Thigh, 
 — the two fets of Branches inofculating with each other. 
 
 Arteria Umbilicalis. — The Umbilical Artery fends cff 
 P,ami Veficales from its under part or beginning ; the reft of it, in 
 the Adult, being fnri veiled into Ligament, as already obferved. 
 
214 
 
 Vesicalis Ima of Haller .—' This is a long and (lender 
 Branch which frequently comes off from the root of the Pudica, 
 and runs to the under part of the Bladder, and to the Prollate 
 Gland. 
 
 Arteria Uterina. The Uterine or Uterine-Hypogaftric 
 Artery, is difperfed upon the Uterus, as has been already tle- 
 feribed. 
 
 IliEMORRHoiDALis Media. The middle Kaemorrhcidal 
 Artery is fometimes fent off from the original Trunk, and at 
 other times from fome of its Branches, as the Pudic in the Male, 
 or Umbilical in the Female. 
 
 ft is chiefly diftributea upon the lower end of the Reftum, 
 where it analtomofes with the Hasmorrhoidalis Interna. It fre- 
 quently fends Branches to the under part of the Bladder, to the 
 Veiiculae Seminales and Proftate in the Male; and to the Va- 
 gina and Bladder in the Female. 
 
 Pudica Communis.—- The Pudica Communis, termed by 
 fome Authors Htzmoi~rhoidalis Externa, belongs to the parts of 
 Generation and Anus, as was for met ly taken notice of. 
 
 Arteria Sciatica. The Sciatic, or Ifchiatic Artery is the 
 largelt of the Iliac Branches, the Glutea excepted. 
 
 It goes through the under part of the Sciatic Notch, accom- 
 panied by the Nerve of that name having the Pyriform Mufcle 
 between it and the Gluteal Artery. 
 
 It afterwards defccnds fomeway down the Thigh, in compa- 
 ny with tite Scialic Nerve, in the hollow between the great Tro- 
 chanter of the Thigh bone and Tuber of the Ifchium, — covered 
 by the Gluteus Maximus Mufcle. 
 
 It fends an Artery backwards, termed A. Coccygea, which 
 creeps along the Sacro- Sciatic Ligaments, furnifhing Branches to 
 the parts about the Os Coccygis, and others which afeend from 
 it, and anaftomofe with fome of the lateral Sacral Arteries 
 through the Holes in the back-part of the Os Sacrum. 
 
 The principal Branches of the Sciatic Artery, however, are 
 difperfed upon the* under part of the Gluten s “Maximus Mufcle, 
 and upon tiiofe at the upper and back-part of the Thigh, where 
 they communicate with the Obturator and Pudic Arteries. 
 
 Arteria Femoralis. 
 
 The Femoral or Crural Artery, — the continuation of 
 the External Iliac, — pafl'es out of the Abdcmen between the Li- 
 gament of Poupart and Brim of the Pelvis. 
 
 At its firfl exit, it is funated fuperficially over the Ball of the 
 Os Ftmoris, having the Flexors of the Thigh between it and the 
 joint. 
 
 Farther down, it is lodged deep in a hollow at the upper and 
 inner part of the Thigh, having the Reflus and Sartorius upon 
 the outer, and the Adduftores Femoris upon the inner fide of it. 
 
215 
 
 Here, it is covered by the Glands of the Groin, and by the 
 general Aponeurolis and Fst ; and from this part it defcends at 
 the in ide of the 'Thigh turning gradually backwards till it reach- 
 es the Ham. 
 
 From the top cf the Femoral Artery, a few fmall Branches are 
 fent off to the Superficial Mufcles and Inguinal Glands, and to 
 the common Integuments at the upper part of the Thigh ; alfo 
 one or two others termed Pudic# Extern#, to the External Parts 
 of Generation and Integuments of the infide of the Thigh. 
 
 About two Fingers-bread' h below the Ligament of Poupart, 
 the Femoral Artery divides, fomewhat like the Common Iliac, 
 into Anterior and Poftenor parts : — The former is the Femoral 
 Artery lhiftly lb called, the latter is termed Profunda Femoris. 
 
 Profunda Femoris. 
 
 The Arterta Profunda, alfo called Vasta, Posterior, or 
 Muscularis Femoris, immediately at its origin from the Fe- 
 moral Artery, gives off two large Branches, — the Circumflex a ln- 
 terna,zx\<\ Cicumflexa Externa , — which run in oppofite directions 
 at the upper part of the Thigh. 
 
 The Circumflexa Interna, though moft frequently com- 
 ing off from the beginning of the Profunda, often arifes higher 
 than it, from the top of the Femoral ; and there are now and 
 then two of them, one a little lower than the other. 
 
 It paffes between the under end of the Pfoas, and the Peftina- 
 lis Mufcle, and afterwards turns round the inner part of the 
 Joint of the Thigh. 
 
 It fends off — 
 
 Large Branches to that portion of the Adduftor Mufcles 
 ■which belongs to the upper part of the Thigh. 
 
 Small Branches to the Mufcles in the vicinity of the Trochan- 
 ters. 
 
 A Branch, termed Articularis Acetakulia to the Capfular Liga- 
 ment of the Joint. 
 
 A Twig, which enters the breach at the underand foie part of 
 the Acetabulum, to he difperfed upon the Ligamentum Rotun- 
 dum and the fubdance called Gland of the Joint. 
 
 A confiderable Branch, which analtomofes with the Trunk of 
 the Obturator Artery And 
 
 Smaller Branches which communicate with the Arteria Sci- 
 atica- 
 
 Circumflexa Externa. — The Circumflexa Externa arifes 
 for the molt part nearly oppofite the former, but frequently a 
 little lower. — Nowand then this artery has a double Origin, one 
 of the Trunks coming off higher than the other. 
 
 It paffes outwards between the upper ends of the Refills, Ten- 
 for Vagins Femoris, and Vaftus Externus Mufcles, and over the 
 Great Trochanter of the Os Femoirs. 
 
216 
 
 It fends Branches upwards to the under part of the Glutei and 
 to other Mufcles placed at the inferior and back part of the Pel- 
 vis, which anallomofe with thofe running down from the Arte- 
 ria Sciatica. 
 
 Others which have more of a lateral dire&ion, and are diftri- 
 buted upon the Mufcles at the upper and back part of the Thigh, 
 and upon thofe more immediately about the Joint, — communica- 
 ting with the Branches of the Circumflexa Interna. 
 
 The largeft Branches defcend between theReflus Femoris and 
 Vaftus Externus ; one, longer than the reft, reaching almoft as 
 far as the outer part of the Knee. 
 
 The Profunda Femoris, having detached the Circumflex Ar- 
 teries, finks deep behind the Trunk of the A. Femoralis, and is 
 fituated upon the Addufdor Mufcles of the Thigh. 
 
 In its defcent it is divided into principal Branches, termed 
 Rami Rerfora?ites, which, after fending off fmall Branches to the 
 Triceps Mufcle, perforate it to be difperled upon the Flexors on 
 the back part of the Thigh. 
 
 The Perforantes come off in the following fucceflion, viz. 
 
 The Perforans Prima , which arifes near the Small Trochan- 
 ter, perforates the Triceps a little farther down, and furnilhes 
 Branches to the Mufcles in the upper and back part of the 
 Thigh. 
 
 It forms numerous Communications with the Circumflex Ar- 
 teries, about the root of the Great Trochanter, and analtomofes 
 in particular with the under end of the Sciatica. 
 
 The Perforans Secunda or Magna, winch comes off fome-way 
 below the former, and is the largeft of the perforating Arteries. 
 
 It gives Branches to the Mufcles in general about the middle of 
 the back-part of the Thigh, particularly to the Flexors of the 
 Leg} and communicates above with Arteries of the Perforans 
 Prima, and with the Circumflex Artei ies. 
 
 Befides thefe, there is one, and fometimes two other perfora- 
 ting Branches, which are greatly inferior in ftze to the two for- 
 mer, and are loft upon the Flexors at the under and back part of 
 the Thigh ; one Twig fent off from thefe fometimes forming a 
 Nutritia or Medullaris of the Os Femoris. 
 
 The Femoral Artery, after giving off the Profunda Femoris, 
 paffes down between the Vaftus Internus and infertion of the 
 Triceps, giving only fmall Branches to the adjacent Mufcles and 
 Integuments. 
 
 About the middle of the infide of the Thigh, it is fituated be- 
 hind the Sartorius Mufcle ; and nearly two-thirds down upon 
 the Os Femoris, it perforates the Triceps, paffing between that 
 Mufcle and the Bone, in its way to the Leg. 
 
 Having parted through the Triceps, it is found in the back- 
 part of the Thigh, where it fends Branches, fometimes termed 
 
217 
 
 Perforates, to the Flexors and Integuments, one Branch, the 
 principal Medullaris, to the fubflance of the Bone, and others to 
 each of the Vafti Mufcles, the Mufcular Branches communica- 
 ting above with Branches defcending from the fuperior parts of 
 the Thigh. In this part of the Thigh it lies clofe upon the Bone, 
 and adheres firmly to it, till it reaches the Ham, where it is 
 termed A. Poplitea. 
 
 Arteria Poplitea. 
 
 The Arteria Poplitea is lodged deep in the hollow be- 
 tween the Ham-ftrings, and between the Condyles of the Os Fe- 
 moris, covered by its aftbciate Vein and Nerve, and generally by a 
 great deal of Fat. . 
 
 It gives off feveral Branches, termed Articulares Superiores and 
 Jnferiores, to the joint of the Knee. 
 
 Four of thefe, fituated, two above and two below the Joint, 
 are more regular and canftant than the reft, viz. 
 
 The Articularis Superior Interna, which turns round the Os 
 Femoris, above the Inner Condyle, paftes under the Semimem- 
 branofus and Semitendinofus ; and, after perforating the Ten- 
 don of the Triceps Mufcle, is difperfed upon the upper and inner 
 part of the Knee, anaftomofing above with Branches fent down 
 from the Femoral Artery. 
 
 The Articularis Superior Externa, which arifes nearly oppofite 
 to the former, paftes outwards between the Tendon of the Bi- 
 ceps and Body of the Os Femoris, immediately above its outer 
 Condyle, and is loft upon the upper and outer part of the Knee ; 
 its Branches anaftomofing with thofe of its fellow, and particu- 
 larly with .the long defcending Branch of the Circumflexa Ex- 
 terna. 
 
 The Articularis Inferior Interna, which arifes oppofite the 
 bending of the Joint, paftes downwards, and then turns round 
 the Tibia, immediately below its Inner Condyle. 
 
 It fiends Branches firft to the back-part, then to the inner fide 
 of the Knee ; fome of them infinuating by the Semilunar Car- 
 tilages into the inner part of the Joint. 
 
 It communicates above with the Branches of the Articularis 
 Superior Interna. 
 
 Tht Articularis Inferior Externa, which comes off near the 
 former, and paftes firft downwards, then outwards, between the 
 External Lateral and the Capfuiar Ligament, to be difperfed up- 
 on the under and outer part of the Knee and inner part of the 
 Joint ; communicating with its fellowof the oppofite fide, and a- 
 bove, with the Branches of the Articularis Superior Externa. 
 
 The other lefs conftant Articular Branches are difperfed upon 
 the Mufcles a little above the Joint. 
 
 VOL. II. T 
 
2 1 S 
 
 The Arteria Poplitea, having furnifhed Branches to the Joint 
 of the Knee, gives others to the Mufcles at the upper and back 
 part of the Leg, two of which, termed Surales, more confidera- 
 ble than the reft, pafsjnto the heads of the Gaftrocnemius Ex* 
 tern us. 
 
 The Trunk of the Artery pafles afterwards between the heads 
 of the external Gaftrocnemius, and commonly from two to three 
 inches below the bending of the Knee, •'and at the under and 
 outer edge of the Popliteus divides into two large Arteries, the 
 ' Tibialis Antica , and Tibialis Pojiica. 
 
 Tibialis Antica. — The Tibialis Antica pafles direftly 
 through the upper end of the Interofleous Ligimentto the fore- 
 part of the Leg. 
 
 In its defcent in the Leg, it adheres clofely to the anterior 
 futface of the Interofleous Ligament ; and has the Tibialis An- 
 ticus on the inner fide, and the Long Extenfors of the Toes on 
 the outer. 
 
 A little above the Ankle, it pafles upon the outer and fore-part 
 of the 'Tibia, and getting under the Annular Ligament and Ex- 
 tenfor Pollicis, it goes along the convex furface of the Foot. 
 
 It lupplies, in general, the Mufcles and Integuments, which 
 belong to the outer and fore-part of the Foot, and ultimately paf- 
 fes into the Deep Mufcles of the Sole. 
 
 Its Branches come off in the following order, viz.— 
 
 A Small Branch lent off before the Tiunk perforates the In- 
 terofleous L'gament, to be difperfed upon the parts near the Joint ; 
 the fuperior Twigs running in a retro rade direffion. 
 
 The Recurrens Anterior, which arifes from the Artery after it 
 has perforated the Ligament, and is difti ibuied upon the Muf- 
 cles at the upper part of the Leg, and upon the Ligaments at the 
 under part of the Knee, anaftomoftng there with the Inferior Ar- 
 ticular Ai teries. 
 
 Numerous Branches fent off in a lateral direfftion to the Mufcles 
 and Integuments on the outer and fore-part of the Leg. 
 
 The Malleoli Interna, which comes off near the lower end of 
 the Tibia, and is difperfed on the parts about the inner Ankle. 
 
 The Malleoli Externa, which arifes a little lower than the 
 former, and is d ftributed to the parts near the outer Ankle. 
 
 The ArteiiaTarfea, which takes its origin a little anteriorly 
 to the bending of the Ankle-joint, and is more conftderable in 
 fize than the Malleolar Branches. 
 
 It pafles obliquely outwards and forwards under the Extenfor 
 Brevis Digitorum, and fends Branches to the Joint of the Ankle, 
 where it communicates with the Malleolar Arteries. 
 
 It fupplies the greater part of the Mufcles, Integuments, & c. 
 on the upper and.outer part of the Foot, and fends Branches 
 termed InteroJJ'ei, to -the Mufcles between the Metatarfal Bones of 
 
219 
 
 the fniall Toes,— which, however, are frequently derived from the 
 Metatarfal Artery. 
 
 The Arteria: Metatarfea , which goes off about the middle of 
 the Dorfum Pedis, aad pafles obliquely towards the root of the 
 Little Toe, aflift'ng the former Artery in furnifhing Branches to 
 the upper part of the Foot and Toes, and fometimes, in part or 
 entirely, iupplying the place ot that Artery. 
 
 The remaining part of the Anterior Tibial Artery afterwards 
 advances between the Extenfor of the gieat, and long Extenfor 
 of the fmall Toes, fending Twigs to the adjacent parts, and di- 
 viding, between the Metatarfal Bones of the Great Toe and that 
 next it, into a Large Pojlerior and a Small Anterior Branch. 
 
 The Pojlerior Branch, which tnay be coniidered as the con- 
 tinuation of the Trunk, finks between the Metatarfal Bones 
 of the two fil'd Toes, and anaftomofes with a deep Artery in the 
 Sole. 
 
 The Anterior Branch runs forwards, under the name of Dor- 
 falis Pollicis, to be difperfed upon the Gi eat and Second Toes. 
 
 Tibialis Postica — The Tibialis Poflica divides about a 
 finger’s breadth under the origin of the Tibialis Antica, into the 
 Fibularis, and Tibialis Pottica ftriSlly fo called. 
 
 The Fibularis, termed alfo Peronea, which is fmaller than 
 either of the Tibial Arteries, runs down at the inner fide of the 
 Fibula, for a confiderable way along the Leg, and is fituated, 
 firft under the Soleus, and then under the Flexor Longus Pol- 
 licis. 
 
 Its Branches are diftributed to the Mufcles at the outer part of 
 the Leg in the nei o hbourhood of the Fibula, — a fmall Medullary 
 Branch alfo penetrating the fubdancc of that Bone. 
 
 A little above the inferior Articulation of the Tibia and Fi- 
 bula, it fends a Branch forwards, termed Peronea Anterior , 
 which perf rates the Interofleous Ligament, and is difperfed up- 
 on the fore-part of the Ankle, where it anadomofes with the Ex- 
 ternal Branch of the Tibialis Antica. 
 
 The continuation of the Trunk, fometimes termed Peronea 
 Pojlerior, defcends behind the Malleolus Externus, to the outer 
 and back-part of the Foot, anaftomofing with the External Mal- 
 leolar and Tarfal Branches of the Tibialis Antica. 
 
 The Tibialis Postica, properly fo caded, pafles down at 
 the back-part of the Tibia, and runs over the Tibialis Podicus 
 and Flexor Digitorum, and under the Gadrocnemius Internus, 
 in its defeent through the Leg. 
 
 Behind the inner Ankle, it becomes more fuperficial, and has 
 the Tibialis Podicus and Flexor Digitorum Longus on the inner, 
 and the Flexor Longus Pollicis on the outer fide of it. 
 
 From the Ankle, it runs in the Hollow of the Os Calcis, and 
 behind the Abduftor Pollicis, to the Sole of the Foot. 
 
220 
 
 Its Branches fuppJy the Mufcles at the back and inner part 
 of the Leg, and the different parts of the Sole ; forming many 
 Inofculations with the Branches of the anterior Tibial and the 
 Fibular Artery. 
 
 In its courfe along the Leg, it gives off — 
 
 Numerous Branches, fimilar to thofeof the Tibialis Antica, to 
 the furtounding Mufcles : 
 
 The Arteria Nutritia Tibia, which begins a little below the 
 upper end of the Trunk, defcends for fome way in the Leg, and 
 gives Branches to the deep Mufcles and Membranes near it, and 
 one Branch termed A. Medullaris , which enters the Hole near the 
 middle of the Bone. 
 
 Several Branches to the parts behind, and at the inner fide of 
 the Ankle and Heel, which communicate with others of the An- 
 terior Tib ; al Artery. 
 
 The Trunk of the Artery divides in the Hollow of the Os Cal- 
 cis, at the place where it is about to go behind the Abduftor 
 Pollicis, into two principal Plantar Branches,— the Interna and 
 Externa. 
 
 The Plantar Arteries run forwards under the Aponeurofis 
 Plantaris, having the Flexors of the Toes between them. 
 
 The Plantaris Interna pafTes near tftfc inner fide of the Sole, 
 between the Aponeurofis Plantaris and Abduftor Pollicis. 
 
 It gives Branches which run in a retrograde dire&ion to the 
 back-part of the Ankle and adjacent parts of the Heel : 
 
 Several Branches from each fide, which go forwards to the 
 Mufcles and Integuments, and other parts at the concave edge of 
 the Sole. 
 
 At the root of the Great Toe, it fends a principal Branch to 
 its inner fide ; it then pafTes under the Flexor Longus Pollicis, 
 and after anaftomofing with the Arcus Plantaris, gives off a 
 large Branch which fplits into two, — one to the outer fide of 
 the Great Toe, and the other to the adjacent fide of the Toe 
 next it. 
 
 The Plantaris Externa, — which may be confidered as 
 the continuation of the Trunk, being in general much larger than 
 the Interna.— pafTes obliquely outwards between the Flexor Bre- 
 vis Digitorum, and Flexor Accefforius, till it reaches the Bale 
 of the Metatarfal Bone of the Little Toe. 
 
 It is afterwards arched forwards between the Flexors of the 
 Toes and Matatarfal bones, the Trunk being continued to the 
 root of the Great Toe, under the name of Arcus Plantaris. 
 
 The External Plantar Artery fends off — 
 
 A Confiderable Branch, firft to the under, then to the outer part 
 of the Heel, which communicates externally with Branches of the 
 anterior Tibial and the Fibular Arteries : 
 
 Several Branches to the Flexors of the Toes, and toother parts 
 n he outer portion of the Sole, which communicate, on the in- 
 
221 
 
 ner fide, with the Branches of the Plantaris Interna, and at the 
 outer with thofe of the anterior Tibial Artery. 
 
 The Arcus Plantaris gives out — 
 
 Several Branches to the deep Mufcles of the Sole, particu- 
 larly, 
 
 Rami Interojj'ei to the Mufcles between the Metatarfal Bones : 
 
 A Branch to the outer fide of the Little Toe : 
 
 Three Large Digital Arteries, which are forked at the roots of 
 the Toes, and run along the edges of thefe, in the manaer the Di- 
 gital Arteries do along the Fingers. 
 
 Between the Metatarfal Bones of the Great Toe and the one 
 next it, the Plantar Arch analfomofes with the pofterioror per- 
 forating Branch of the anterior Tibial Artery, forming a free 
 communication between the Arteries of the upper and under fide 
 of the Food. Frequently it fends off here a Digital Artery, 
 which forks and runs along the outer frde of the Great Toe, and 
 inner fide of the Toe next it, fo as to fupply the place of one of 
 the Branches of the Internal Plantar Artery. 
 
 At the roots of the Toes, the Interoffeous Arteries of the up- 
 per part of the Foot, alfo form diftinft ar.aftomofes with the an- 
 terior extremities of the Trunks of the Digital Arteries. 
 
 VEINS. 
 
 The Veins of the Inferior Extremities, like thofe of 
 the Superior, confift of a Subcutaneous and Deep fet, and, like 
 them alio, are furniflied with numerous Valves. 
 
 Subcutaneous Veins. — The Subcutaneous Veins are fitu- 
 ated between the Common Integuments and General Aponeuro- 
 lis, and, in many parts, are entirely concealed by the Fat. They 
 anaftomofe frequently with each other by large Branches, and 
 have ftveral communications alfo with the deep Teated Veins. 
 
 They form two principal Trunks, called Saphxna Major and 
 Saphena Minor ; — the term Saphaeena applied, from the Vein 
 being luppofed to be always vijible. 
 
 The S a r h /e N a Major begins upon the upper fide of the 
 Foot, runs over the fore-part of the inner Ankie, and afcends in 
 the Leg at the inner edge of the Tibia. 
 
 From the Leg, it paifes up by the infide of the Knee, and af- 
 terwards, from the inner to the upper and fore-part of the 
 Thigh. 
 
 It is at firft compofed of Veins, derived from the upper and in- 
 ner part of the Dorfum Pedis, which have frequent aaaftoinol’es 
 with each other, and are of coniiderable fize, 
 
 Vol. II. T 2 
 
 i 
 
In its afcent it is joined by Brandies from the fuperficial 
 parts of the Leg, and is frequently fplit into a Plexus, fome wav 
 below the Knee. 
 
 It receives Branches from the fuperficial parts of the Thigh, 
 and fma'U Twigs from the Inguinal Glands. 
 
 It terminates in the top of the Femoral Vein, nearly oppofite to, 
 ora little higher than, the origin of the Arteria Profunda. 
 
 The Saphena Minor arifes upon the outer fide of the Foot, 
 and afterwards paffes behind the Malleolus Externus. 
 
 From this, it afcends in the back-part of the Leg, upon the 
 furface ot ihe Gaftrocnemius Externus, and goes into the ^lam. 
 
 It is formed by the Veins of the upper and outer part of the 
 Foot, and is joined to the Saphasna Major, over the Metartarfal 
 Bones, by one or more Arches, which receive a Plexus of Bran- 
 ches into their lower or convex part. 
 
 It is joined by the fuperficial Veins of the outer and back-part 
 of the Leg, which have frequent anaftomofes with each other, 
 and with the Branches of the Saphasna Major. 
 
 It terminates in the Vena Poplitea, and communicates con- 
 ftantly by a fmall Branch with the Saphaena Major, a little 
 above the Knee. 
 
 Deep Veins. The Deep Veins of the Leg, like thofe of the 
 Fore-arm, run clofe at each fide of their Arteries, and are dou- 
 ble their number, but differ a little from the Radial and Ulnar 
 Veins, in being proportionally larger. 
 
 The Tibial and Fibular Veins anaftomofe in fome places 
 with each other, and alfo communicate with the Subcutaneous 
 Veins. 
 
 At the upper part of the Leg, they are united together, to form 
 the Vena Poplitea, and the union is nearly at the fame place 
 where the correfponding arteries come off 
 
 The Vena Poplitea adheres clofely to the upper furface of 
 the Artery, which it in a great mealure conceals, and is com- 
 monly fingle, excepting a fmall Vein which fometimes accom- 
 panies and communicates with it. 
 
 The Popliteal Vein receives the Venae Surales and Articulares, 
 and the Saphaena Minor; after which it forms the Femoral Vein. 
 
 The Vena Femoralis receives the Veins which correfpond 
 with the perforating Branches of the Femoral Artery, and paffes 
 in through the Triceps, where the Artery cornesout. 
 
 In the middle of the Thigh, it lies deeper than the Artery, 
 afterwards turning gradually to its inner fide ; and at the upper 
 part of the Thigh, it is joined by the Vena Profunda. 
 
 The Vena Prounda receives the Veins correfponding with 
 the Branches of the Artery of that name, and is fometimes of a 
 large fize, being then in a great meafure the continuation of the 
 Vena Poplitea, a fmall Vein only in fuch cafes accompanying 
 the Trunk ot the Femoral Artery. 
 
223 
 
 Befides the Vena Profunda, the Femoral Vein takes in fmall 
 Veins from the External parts of Generation, from the Ingui- 
 nal Glands, and from the other fuperficial parts of the Groin : 
 -—and, in particular, it receives a Branch of confiderable fize, 
 which defcends from the Integuments of the fore-fide of the Ab- 
 domen. 
 
 The Trunk of the Femoralis, having received the different 
 Veins of the Inferior Extremity, pafles into the Abdomen, be- 
 hind Poupart’s Ligament, being ttill fituated at the inner fide 
 of the Artery, — after which it forms the Iliaca Externa. 
 
 The Iliaca Externa receives into its beginning the Epi- 
 gaftric, and Circumflex Vein of the Os Ilium, and fometimes the 
 V. Obturatrix. 
 
 It is fituated at the infide of the External Iliac Artery, and 
 afterwards erodes behind it on the right, and behind the Inter- 
 nal Iliac Artery on the left fide of the pelvis, to join the Trunk 
 of the Hypogaftric Vein. 
 
 The Vena Hypogastric a, or Iliaca Interna, is fitu- 
 ated at the outer fide of the Artery and receives the different 
 Veins which correfpond with the Branches of the Hypogaftric 
 Artery, and which are furnifhed with Valves where they are 
 fituated among the Flefhy parts of the Pelvis. 
 
 The External and Internal Iliacs unite and form the Common 
 Iliacs, a little below the divifion of the correfponding Arte- 
 ries. 
 
 The Iliac.® Communes afeend by the right fide of their 
 refpadlive Arteries, and a little below the the Bifurcation of the 
 Aorta,— or upon the fore part of the Fifth Lumbar Vertebra, — 
 unite to form the Inferior Cava, fituated, as formerly mentioned, 
 at the right fide of the Aorta. 
 
 The Vena Cava Inferior, — which is much larger than 
 the Cava Superior, and greatly exceeds in fize the defeending 
 Aorta,— receives, at its beginning, the Vena Sacra, and higher, 
 the Venae Lumbares, which, in the left fide, pafs behind the 
 Trunk of the Aorta. 
 
 It likewife receives the Venae Renales, and the Spermatica of 
 the right fide. 
 
 At length it takes in the Venae Hepaticas and Diaphragma- 
 ticae, and perforating the Diaphragm at the root of the Liver, it 
 terminates in the Right Auricle of the Heart. 
 
224 
 
 PART VII. 
 
 OF THE 
 
 NERVES IN GENERAL . 
 
 T HE Nerves are firm, white Cords, which are generally 
 confidered as being direftly continued from the Medullary 
 Subftance of the Brain aftd Spinal Marrow ; — although inftan- 
 ces have been frequently met with, where the Brain, and even 
 the Spinal Marrow, have been found nearly obhteratcd in the 
 Foetus, and yet the Nerves retained their ufual appearance. 
 
 They’ are e .mpofed of Funiculi clofely connected, and each of 
 thel'e again of fmailer Fibrilla: which may be fubdivided into parts 
 fo extremely minute, as almoft to elude the naked Eye, but 
 which may be readily feen by the afiiftance of the M crolcope : 
 -—No Cavity, however, has been yet obferved in them. 
 
 The Medullary Part of the Fibrillae appears to be furniftied 
 with Cineritious Subftance derived from their Pia Mater; in 
 proof of which, they are obfeived to be in general of a browner 
 colour than the Medullary Subftance of the Brain, and larger 
 in their courfe than at their fuppofed origin. — M on-ro’s Obf. on 
 Nerv. Syjl. 
 
 The Medullary Subftance of the Fibrillae is pulpy and tender, 
 but rendered thicker and ftronger by the coverings they receive 
 from the Tun ca Arachnoidea, and Pia Mater, while within the 
 Bones, and more particularly by the additional covering given 
 them by the Dura Mater upon their exit. 
 
 The Dura Mater, in its paffage through the Bafe of the Cra- 
 nium, and between the different Vertebrae, is connected by its 
 External Surface to the Pericranium and Periofteum; while 
 the inner part of it, together with the Tunica Arachnoidea and 
 Pia Mater, is continued along the Nerves. 
 
225 
 
 The Involucre., or Coverings, inclofe each of the Nerves in 
 genera!, and likewife the fevera! Fibrillae of which they are com- 
 pofed, whereby their fize, as well as Itrength, is greatly in- 
 creafed. 
 
 The Nerves, foon after leaving the Bones, have the Dura 
 Mater fo intimately connected with them, that it has been con- 
 fidered by fome Authors, as degenerating into condenfed Cellular 
 Sublfance, notwithftanding it itill retains the general appearance 
 of the^Dura Mater. 
 
 Upon examining the Nerves, efpecially the fmall ones, in a 
 living or recently dead animal, they are obferved to have nume- 
 rous White Lines placed tranfverfely, or in a Terpentine direction. 
 —Obf. on Nerv. Syfi. Tab. XIII. 
 
 When the Nerves are moderately ftretched, this appearance 
 becomes lefs evident; and when extended conliderably, or when 
 macerated in water, it vanilhes entirely. 
 
 Prochaska (Be Carne Mufculari) fuppofes thefe Serpen- 
 tine Lines to be owing to a decuffation of Veflels and Fibres of 
 Cellular Sublfance ftraitening the Nerves. 
 
 Dr. Monro confiders them as Folds or Joints allowing the 
 Nerves to accommodate themfelves to the various ftates of Flex- 
 ion and Extenfion. 
 
 The Nerves are fupplied with Arteries from the neighbouring 
 Blood- veflels, to which they fend correfponding fains. 
 
 Thefe, however, are fmall, and difficult of injection, except- 
 ing in the large Nerves, where the Velfels are more confiderable, 
 and where, after a minute injection, the Nerve receives the colour 
 cf the matter injeCted. 
 
 Upon dividing the Nerves, they are not found to poffefs much 
 contraFlilily ; while the Arteries, upon being cut are obferved to 
 retraCt very confiderably . 
 
 They are generally lodged in the common Cellular Subftance 
 and Fat, and in the Interftices of the Vifcera and Mufcles, where 
 they are prevented from being compreffed ; though in feveral parts 
 they are expofed to the hardnefs of Bones, or to the aCtion of 
 Mufcles, over or through which they pafs. 
 
 In their courfe through the different parts of the Body, they 
 generally run as ftraight as is confident with the nature of the 
 particular part over which they pafs, an J their own fafety. 
 
 In their progrefs, they divide into Branches, which become 
 gradually fmaller, and which, though taken collectively, are in- 
 ferior in fize to the Trunks from which they iffue. 
 
 The Branches generally run off at acute angles ; but in feveral 
 places they have a retrograde direction. 
 
 They have commonly the fame kind diftribution in the oppofite 
 tides of the fame SubjeCt, and vary little in this refpeCt in diffe- 
 rent Subjects. 
 
226 
 
 In fome parts of the Body, feveral Nerves unite together, and 
 form a Plexus or Net-work ; in other , they unite into a Connnon 
 Trunk-, and in many, by fuch an union, a hard knot, termed 
 Ganglion, is formed. 
 
 When tlie Plexufcs, or the Common Trunks, are minutely ex- 
 amined by flitting open their coverings, it is found, that their 
 Fihriliae are intermixed in fuch a manner, that each of the 
 Nerves pafling out from the Plexus, or from the Common Trunk, 
 is comp ,fed of Fibrillae from feveral, or from ail the NerTes 
 which en ered it, in confequence of which, the Organs in gene- 
 ral are furn ftud with Nerves fiom various fources. Obf. on 
 Nerv. Syft. 
 
 The Ganglia differ from each other in flze and figure : They 
 have thicker Coats and are more Vufcular than the Nerves ; and 
 are larger than the whole of the Nerves, taken conjunftly, which 
 entc-r into or go out from them. — f hey are fuppoled to ferve as 
 fiefh fources of Nervous Influence. 
 
 They a e computed of Neivous Fibrillx, covered by fomething 
 like a Cineritious Matter, and are fo divided, multiplied, and 
 intei mixed, that each of the Nei ves pafling out from a Ganglion 
 is found to be compof'ed of Fibrillae derived from the greater part 
 of the Nerves which enter it. — Obf. onNerv. Syft. 
 
 Where Nerves pals out from the fide of a Ganglion, they 
 are compofed of Fibrillae which come off in contrary directions ; 
 — the one let from the beginning, the other from the oppo- 
 fite extremity of the Ganglion. 
 
 The Nerves which go out from the different Ganglia have the 
 fame ftru&ure with thole which enter them, but are found, with 
 only a few exceptions, to be rather la.ger. 
 
 In the Trunk of a Nerve, the Cords appear to run parallel to 
 each other ; but when macerated in water, fo as to diffolve the 
 Cellular Subftance, or when otherwife accurately examined, they 
 are feen evidently to intermix fomewhat after the manner of the 
 Fibrillae in the Plexus, or in the Ganglia. — Obf. on Ner<v. 
 Syft an. 
 
 The Termination of the Nerves is fuft, pulpy, and pellucid, 
 as is dill ndtly feen in the Retina of the Eye or Ear ; the exter- 
 nal Covering being entirely laid afide, while the Pia Mater, in 
 particular, accompanies them throughout. 
 
 The Nerves preferve the motion of the Mufcular Fibres. 
 
 They conflitute the immediate Organs of Senfation, and con- 
 vey Impreflions made upon them to the Mind. 
 
 The manner in which thefe Impreflions are produced,— whe- 
 ther by a Vibration communicated to the Nerves; or by a Liquid 
 called Nervous Fluid, contained and moving in them or by an 
 eleftric Matter common to them and many other fubftances ; or 
 in what manner that power a els, termed Animal Electricity, 
 
227 
 
 which has been la'ely difcovered to take place in the Animal 
 Kingdom, upon the application of certain Metals ; is not yet 
 underftood. 
 
 DISTRIBUTION OF THE NERVES. 
 
 THE Nerves are diftinguifhed into two Clafles ; one arifing 
 from the Biain, termed Cerebral ; the other from the Spinal Mar- 
 row, teimed Spinal Ner-ves. 
 
 The Cerebral Nerves-are generally reckoned Nine or Ten Pairs 
 in number, befides a particular Pair, which has the name of 
 Sympathetic. 
 
 They pafs through the Holes iu the Bafe of the Cranium, and 
 receive their refpeftive Names according to their order ; or from 
 their Functions 5 or from the parts on which they are difperfed, &c. 
 
 The Spinal Nerves con fill of Tnxienty-Nine or 7 hirty Pairs, 
 which pals out between the d fferent Vertebrae, befides a Pair 
 called Accejfory, which enter the Cranium from the top of the 
 Spinal Marrow, and afterwards pafs out with one of the Cerebral 
 Nerves. 
 
 Nerves which pass through the Base of the 
 Cranium. 
 
 The First Pair, or Olfactory Nerves, — arife, on 
 each fide of the Brain, by three feparate Striae, from the Cor- 
 pora Striata, at the under and back-part of the Anterior Lobes, 
 near where the Carotid Arteries enter the Fijfures of Sylvius. 
 
 They are more tender than the other Nerves, and alfo differ 
 from them in not being compofed of Fafcicub. 
 
 They run each in a Furrow, upon the under Surface of the 
 Anterior Lobes of the Brain, converging a little and becoming 
 fomewhat larger, till the) reach the Cribriform Plate of the 
 OEthmoid Bone. 
 
 Upon this Plate, each forms an Oblong Bulb, which, in colour 
 and confidence, rei’embles the Cortical part of the Brain, but is 
 mixed with (Leaks of Medullary Matter. 
 
 From this Bulb, numerous Nervous Filaments are fent off, 
 which pafs through the Holes tf ihe Cribriform Plate, and now 
 become firm and ftrong like the other Nerves, by receiving a co- 
 vering from the Dura Mater. 
 
 After entering the Nofe, they divide into two Portions or 
 Planes, — one paffing on the Septum, the other upon the Olfa Tur- 
 binara, and other parts oppofite to the Septum, and both running 
 at firft in Grooves of the Bones. 
 
22S 
 
 They form a beautiful Plexus, which is fpread out upon that 
 fide of the Membrane of the Nofe which is contiguous to the 
 Bones, and may be traced a confiderable way upon it in diftinfl 
 Threads, which becoming gradually fmaller, fink, into the Mem- 
 brane, and are fuppofed to terminate on the 1'uiface next the Ca- 
 vity of the Nofe, theie conftituting the Organ of Smell. 
 
 The Second Pair, or Optic Nerves, — which are of great 
 fize, arife from the Thalami Optici, and are connefled in their 
 paffkge to Tubercles at the root of the Infundibulum, which 
 furnifh them with an addition of Medullary Subftance. 
 
 They are of a purer white than other Nerves, having lefs Ci- 
 neritious Matter entering their compofition, and differ alfo in 
 the Pia Mater furn fhing them with a general Covering, before 
 it invelts the feverai Falciculi of which they are formed. 
 
 At the fore part of the Sella Turcica, they unite, and have 
 their Medullary Parts intimately intermixed. 
 
 From this union, they go obliquely outwards and forwards 
 through the Foramina Optica into the Orbits; and advancing in 
 the Orbits in a waving dirtflion,— i o prevent them from being 
 over-lfretched in the motions of the Eye, — they perforate the 
 Balls, to be expanded into the Retinae, which have been already 
 deferibed. 
 
 The Third Pair, or Motor es Ocui.orum, — fmaller than 
 the Optic Nerves, — arife at the under, inner, and back-part of 
 the Crura Cerebri, or between the Corpora Albicantia and Tu- 
 ber Annulare, by numerous Threads which are foon collefted 
 into their refpe&ive Trunks. 
 
 They pafs outwards, perforate the Dura Mater at the (ides of 
 the Porter ior Clinotd Procefs, and running along the upper part 
 of the Cavernous Sinus, at the outfide of the Carotid Arteries, 
 they get through the Foramina Lacera into the Orbits. 
 
 Upon entering the Orbits, they divide into feverai Branches, 
 which fupply the greater number of the Mufcles of the Eye, in 
 confequence of which the Nerves have obtained their particular 
 name. 
 
 A Btanch runs to each of the Mufcles within the Orbit, ex- 
 cepting the Trochlearis and Abduftor ; and the Nerve likewife 
 aflilts in forming a final) Ganglion, termed Optbalmic, from 
 which Twigs are fent off to fupply the Ball of the Eye. 
 
 The Fourth Pair, or Pathetic. — have their origin the 
 higheft of the Cerebral Nerves, and are the moft (lender of the 
 Body, being generally formed of one Fafciculus only on each 
 fide. 
 
 They arife by a Angle, and fometimes by a double root, behind 
 the Teftes, from the Medullary Expanfion which lies over the 
 paflage to the Fourth Ventricle, and which unites the Proceflus 
 ad Teftes to each other. 
 
229 
 
 They afterwards turn round the Crura Cerebri, and perforate 
 the Dura Mater at the edges of the Tentorium, fome way behind 
 the entrance of the Third Pair. 
 
 They run afterwards along the Cavernous Sintifcs, at the outer 
 fide of the Third Pair, then crol's over that Pa c, and pa.Ting 
 out of the Cranium through the Foramina Laceri, the. go ob- 
 liquely over the Mufcles at he upper part of the Orbits, to be 
 entirely d.fperfed upon the Pathetic or Trochlearis Mui’cles. 
 
 The Fifth Pair, or Par I rigeminum, — which are the 
 largeft Nerves of the Brain, arife, each by an an erior fmall, and 
 a pofterior large Portion, from the fide of the Tuber Annulare, 
 where the Crura Cerebelli join it. 
 
 They enter the Dura Mater a little below the Tentorium, over 
 the points of the Partes Petrofae of the Temporal B ties, and 
 form a Plexus on each fide, in which upwaids of fifty Faicicu- 
 li have frequently been enumerated. 
 
 The Plexus finks clofe by the outfide of the Cavernous Sinus, 
 concealed by a doubling of the Dura Mater, and foirns a Gang- 
 lion fometimes called Gajferion , after Gasser, who, if not the 
 Difcoverer, was the firft who illuftrated it. 
 
 The Ganglion is of a fem’lunar firm, and placed tranfverfely 
 with refpefl to the Trunk, of the Nerve. 
 
 From the oppofite and curved edge of the Ganglion, three large 
 Branches come out ; the firft and An erior, termed Ophthalmic , 
 —the fecond and Middle, the Superior Maxillary , and the third 
 nd Polferior, the Inferior Maxillary . 
 
 The First Branch of the Fifth Pair, — at the fide of the 
 Sella Turcica, is fituated lower than the Third Pair, and after- 
 wards erodes over it, being previoufly connefted by Nervous 
 Matter to the Trunk of the Fourth Pair. 
 
 It goes through the Foramen Lacerum into the Orbit, and is 
 there divided into the following Branches, viz. 
 
 The lupra-Orbitar, which is the largeft of the whole, being 
 a continuation of the Ophthalmic. 
 
 It pafles immediately under the Membrane which lines the up- 
 per part of the Orbit, and fplits into two branches of unequal 
 fize. 
 
 The fmaller Branch termed Supratrochlearis, runs under the 
 Superciliary Ridge to the Upper Eye-lid and Fore-head. 
 
 The larger paffes through the Foramen Supra-Obitarium,— or 
 over the Superciliary Ridge when the Foramen is awanting,— 
 fends Branches to the Upper Eye-lid, and divides into feveral 
 others, which run back partly above, but chiefly under the Fron- 
 tal Mufcle, to fupply the fore at d upper part of the Head in ge- 
 neral, while minute Fibres appear to penetrate the Bones. 
 
 The Nafal Branch , which runs obliquely over the Optic 
 Nerve, where it detaches a Filament or two to the Eve, them 
 under the Levator Mufcles of the Eye-lid and Eye: and getting 
 
 Vol. II. U 
 
230 
 
 between the Abdu&or Oculi and Trochlenris, pafles to the infide 
 <of ihe Orbit. 
 
 It fends a Branch, which after entering the Foramen Orbitari- 
 um Internum Anterius, re-enters the cavity of the Cranium, and 
 gets upon the Cribriform Plate of the OEthmoid Bone. 
 
 From thence it pafles down through one of the anterior Holes of 
 this Plate, and fends Twigs to tho membrane at the anterior part 
 of the Nolttil, while the Nerve defcendi ng at the fore part of the 
 Septum Narium, is difperfed upon the point and Wing of the 
 Nofe. 
 
 The continuation of the Nafal Branch, new called Infratroch- 
 learis, paffes forwards to the inner Corner of the Eye, and is 
 -diftributed upon the Lacrymal Sac and parts adjacent. 
 
 The Lacrymal Branch, which runs along the Abduftor Oculi 
 Mufcle, fends Twigs to the Membranes and Fat near it, likewife 
 one or two through the Subftance of the Cheek-bone, and one in 
 particular to the Subftance of the Lacrymal Gland, while ano- 
 ther paffes over the Gland, and vanifhes in the neighbouring 
 parts. 
 
 A Branch to the Ophthalmic Ganglion, which is fometimes fent 
 off from the Nafal, at other times from the Ophthalmic Trunk. 
 
 The Ophthalmic Ganglion, — termed all'o Lenticular, from its 
 fhape, is formed by this Branch from the Fifth, and by another 
 from theTh'rd Pair, and is commonly the fmalleft in the Body. 
 
 It is of an oblong form and compreffed, is fituatedat the out- 
 did e of the Optic Nerve a little before its entrance into the Orbit, 
 and is concealed in Fat. Sometimes, though rarely, the Fila- 
 ments which form it take their origin entirely from the Third 
 Pair. 
 
 From the Ganglion, about a dozen of" Filaments arife, termed 
 Ciliary Nerves, colle&ed into two Portions, which cteep along 
 the oppofite tides of the Optic Nerve, feparated a little from each 
 other and running in company with the Ciliary Arteries. 
 
 Befides the Ciliary Nerves from the Ganglion, one and fome- 
 times two Filaments arife from the Ramus Nafalis, and pafs 
 along with the other Ciliary Branches, 
 
 The Ciliary Nerves, running with fcarcely any divifion, reach 
 the back-part of the Eye ; and a little before the Infertion of the 
 Optic Nerve, enter the Sclerotic Coat, pafs obliquely through it, 
 -and about the middle of the Ball, appear upon the Surface of the 
 Tunica Choro'des. 
 
 Upon this Coat, they run flat, and in a parallel dire&ion, 
 fending very few evident Branches, either to it or to each other, 
 till they reach the Ciliary Circle, where they divide into nume- 
 rous minute Filaments. 
 
 Upon the Chotoides, five or fix are larger than the reft, fome 
 being fo minute as almoft toefcape the naked Eye. 
 
231 
 
 At the Ciliary Circle, each commonly divides into two Bran- 
 ches, which are covered by the Cellular Subftance of the Circle ;■ 
 and thefe, at th. n>ot of the Irs, are fubdividcd into ftill fmaller 
 Branches, which mu in a radiated and waving dire&ion, the Ci-- 
 liary Veflels being interpofed. 
 
 Near the inner -dge of the Pupil, they are united into Arches,’ 
 from wlvch very minute Twigs run to the interio r margin of the 
 Iris. 
 
 The Second Branch, or Superior Maxillary Nerve, 
 —is larger than the Ophthalmic, and is principally difperfed 
 upon the Parts belonging to the Upper Jaw, trom which ir has 
 its name. 
 
 It goes through the Foramen Rotundum of the Sphenoid Bone, 
 and at its exic divides into numerous Branches, viz. 
 
 The Spheno- P alatine, or lateral Nafal Ner-ve, which fends a 
 reffcft-d Branch through the Foramen Pterygoideum of the Sphe- 
 noid Bu ie, to join the Sympathetic Nerve in the Canalis Caroti- 
 cus, and a Branch winch en.eis the Foramen Innominatum of the 
 Pars Petroi’a, to join the Portio Dun of the Seventh Pair. 
 
 Tile Lateral Slain Nerve goes afterwords into the Spheno- 
 palatine Hole, to be dilpened upon the under and back-part of the 
 Septum," and oppoiiie fide of the Nofe, ami upon the Membrane 
 of the Sphenoidal Smus and Euttachian Tu: e : One Branch in 
 Dart icular, atter ... ;g along the Septum, -rues throuca the F«-- 
 ramcn Incifivum ■ . le Roof of the Mouth. 
 
 The P alato Iy atctlla -j , or Palatine , Branch . which defcends 
 through the Canal .eudiug r lie Foramen Paiat'num Poller i us j 
 and running near i ae Aiv; with con ei'poml ng Biood -veflels, 
 fends Branches to the Velum F a and Roof of the M m,h, and 
 Minute F 'aments wh : h penetrate into the Palate plate of the 
 Superior Maxillary Bone. 
 
 Small Branches, waich pals round the Upper -Jaw, and vanilla 
 in the Cheek. 
 
 A Twig, which goes through the H de in F O- Mils?, along 
 with a Branch of the Ocular Artery, to ik - 
 
 Small Filaments, which run down uuo ■ . h ,r n - ; - c • f . he Su- 
 perior Maxillary Bone, and fupply the fu dime die Up.-r- 
 Jaw, tne large Dentes M.olares, and Nlcunbiane lnurp the t a - 
 trum Maxillare. 
 
 The Second Part of the Fifth Pair after fending off theft- af- 
 ferent Branches, goes into the Canal under the Oibit, and fotras 
 the Infra-orbitar Nerve, which, while in the Can- 1, gives off 
 Filaments pafling through minute Conduits in the Upper Jaw. to 
 the Antrum, to the Subftance of the Bone, to the fimll Mod ,-cs, 
 Caninus, Incifores, and Fore-Teeth ; and fometimes a Tv 
 the companion of a fnial! Branch of the Internal Maxillary Ar- 
 tery, to the Membrane lining the Orbit. 
 
S32 
 
 The Jnfra-Orbitar Nerve pafles afterwards out of the ForameE 
 Infra Oibitariuin, and divides into many large branches, to be 
 diftn'uited upon the Check, Und er Eye-lid, Upper Lip, and fide 
 of the Nufe. 
 
 Tiie Third Branch, or Inferior Maxillary Nerve, 
 goes i hough - he Foramen Ovale of the Sphenoid Bone, and Top- 
 plies i he parts belonging to the Under Jaw, and the Mufcles fitu- 
 ated between it and the Os Hyoides, by the following Branches, 
 Viz. 
 
 One, or fomeimes two Deep Temporal Branches, to the inner 
 part of the Temporal Mulcle. 
 
 Branches, to the Maffeter, Pterygoideus, and Buccinator 
 Mufcles. 
 
 A Branch wh ch pafles behind the Cervix of the Lower Jaw, 
 and r ives off Filaments to the fore-part of the Ear, and after- 
 wards accompanies the Temporal Artery upon the fide of the 
 Head, where it terminates. 
 
 A Branch, to the Buccinator Mufele and other parts of the 
 Cheek. * 
 
 A Nerve of confiderable fixe, termed Lingual or Gujlatorius, 
 which pafles between the Pterygoid Mufcles, to the inner of 
 which it gives lome Filaments. It then fends off, from its un- 
 der fide, a Ganglion which tranfmits Nerves to the Inferior Max- 
 illary Gland. 
 
 The Lingual Nerve alfo tranfmits feveral Branches to the Sub- 
 lingual Gland, and to the Mufcles of the Tongue. 
 
 It tei minutes, at length, near the Point of the Tongue, by 
 many Branches which belong chiefly to the Papillae ; in confe- 
 quence of which this Bianch is confidered as the principal 
 Nerve of the Organ of Tafte. 
 
 The .Trunk of the Inferior Maxillary Nerve, having parted 
 wit'n the Lin ual Nerve, direfls irscourfe between the Pterygoid 
 Mufcles to the Polierior Foramen of the Infeiior Maxillary 
 
 Canal. 
 
 Before entering the Canal, it fends off a long and {lender 
 Bianch, which is lodged at firft in a Furrow of the Bone, and 
 goes afterwards to be difperfed chiefly upon the Mylo-hyoideus 
 Mufele and Sublingual Gland. 
 
 The Trunk of the N'-rve is afterwards conduced along the 
 Canal of the Jaw under the Alveoli, where it diftributes Fila- 
 ments to the different Teeth of the cot refponding fide, and to 
 the Subflance of the Bone : and coming out of the Canal by the 
 Anterior Maxdlary Foramen, fomewhat diminiflied in fize, it 
 fcatters its remaining Branches upon the Chin and under Lip. 
 
 The Sixth Pair, or Abducentes, arife from the begin- 
 ning of the Medulla Oblongata, at the pait common to the Tu- 
 ber Annulare and Corpora Pyramidalia, and are the fmallelt of 
 the Cerebral Nerves, the Fourth Pair excepted. 
 
233 
 
 They perforate the Dura Mater at the inner, fide of the en- 
 trance of the Fifth Pair, and run forwards within the Cells of 
 the Cavernous Sinus 5 but fo funounded by Cellular S 1 1 bltance, 
 as to feem to be protefled from the Blood of that Receptacle. 
 
 While in the Sinus Cavernofi, they are Situated between the 
 Ophthalmic Nerves and Carotid Arterie-, upon the furface of 
 the latter of which they fend off two or three Filaments on 
 each fide of the Head, to ailift in forming the Great Sympathetic 
 Nerves. 
 
 The Trunks of the Sixth Pair afterwards go through the fo- 
 ramina Lacera, to be dilperfed entirely upon the Abductor Mui- 
 cles of the Eyes. 
 
 The Seventh Pair is compofed, on each fide, of two porti- 
 ons, — the Nervus Auditorius, Nervtis Acujiicus , or Portio Mollis ; 
 and the Cotnmunicam Faciei, or Portio Dura. 
 
 The Portio Mollis, is the fofteft of the Nerves, excepting 
 the Olfaftory. 
 
 It arifes by tranfverfe Medullary Striae from the anterior 
 part of the Fourth Ventricle, and is feparated from its fellow of 
 the oppofi e fide only by the Crena of the Calamus Scriptonus. 
 
 The Striae, tuining round the Medulla Oblongata, apply 
 themi'elves to the Tuber Annulare, from which they receive an 
 addition of fubltance, and then get to the hde of the Portia 
 Dura. 
 
 The Portio Dura, fometimes alfo called Syjnpatbeticus Mi- 
 nor , arifes from that part of the Brain which is common to the 
 Pun; Varolii, Crura Cerebelli, and Medulla Oblongata ; and 
 at its origin, is fituated upon the inner fide of the Portio Mol- 
 lis. 
 
 Between the origin of the Portio Dura and Trunk of the Por- 
 tio Mollis, a fmail Nerve arifes, termed by. Wrisberg, Portio 
 Media inter P. Duram et P. Mollem. . 
 
 It comes off by rn.nute Fibrillae, which foon unite into a 
 Trunk, from the pofierior pari of the Pons Varolii, or from 
 the adjoining part of the M Julia Oblongata, and is an Accelfory 
 Nerve of the Portio Dura. 
 
 The Port o Dura, conliderably fmaller than the P. Mollis, 
 gets into the Meatu - Aud tonus Interims, and is there lodged 
 in a kind of half-lheath, formed by that Nerve, to which it is 
 connefted by fine Cellular Subftance ; the Dura Mater, which 
 lines the Palfage, giving here a general Covering to both Nerves. 
 
 Portio Mollis.— The Portio Mollis is formed of two Faf- 
 ciculi, nearly of equal fize, one of which belongs to the Cochlea, 
 the other to the Veifible and Semicircular Canals. 
 
 Each of thefe Fafciculi pafies by numberlefs Fibrills through 
 the Cribriform Plate in the bottom of the Meatus Auditorius lu- 
 ternus, to the inner parts of the Labyrinth. 
 
 Vol. II. U 2 
 
234 
 
 TheFibrillae deftined for the Cochlea go through the Holes in 
 the fides of the Modiolus. 
 
 Some pafs between the Plates which form the Septa of the Gy- 
 ri ; others go through Holes between the Offeous Plates of the 
 Lamina Spiralis ; but by much the greateft number perforate the 
 ftdes of the Modiolus, between the Septum of the Gyri and the 
 Lamina Spiralis. 
 
 The larger F brills run upon the Membrane covering the La- 
 mina Spiral i s ; while the fmaller go from the Modiolus, between 
 the Olfeotis Septa and on the inner (ides of the Gyri, to be dif- 
 perfed upon the Membrane lining them. 
 
 The remaining Fibrillae perforate the Plate common to the Mo- 
 diolus and Infundibulum, and vanifh upon the laft half-turn of 
 the Lamina Spiralis and the Cupola of the Cochlea. 
 
 Upon the Ofieous part of the Lamina Spiralis, the Nerves have 
 the common appearance ; but upon the Membranous Portion, 
 they are of the colour of the Retina of the Eye. 
 
 In the whole of their courfe upon the Lamina Spiralis, they 
 form a real Retina ; though the reticulated ftrufture becomes 
 much lefs apparent upon the outer part of this Lamina, and upon 
 the continuation of the. Membrane lining the Gyri, — the Nerves 
 feeming to terminate in a femipellucid Pulpy Membrane refem- 
 bling the Retina of the Eye. 
 
 The Membrane upon which the Nerves are expanded, is but 
 flightly conne£ted to the Periofteum which lines the inner fide 
 of the Cochlea, and which, though thin, may be readily percei- 
 ved, being painted with Blood-vefTels ,— nor does it differ from 
 the Periofteum lining the Tympanum. — See Dr. Monro’s 'Trea- 
 tife on the Ear. 
 
 The Fafcicuius which belongs to the Veftible and Semicircular 
 Canals, forms at full a Plexus, then a Gangliform Enlargement, 
 previous to its entrance into the Labyrinth. 
 
 The Neives which belong to the Veftible and Semicircular Ca- 
 nals pafs through the Macula Cribrofa, or Holes fubdivided into 
 fmaller Holes by Cribriform Plates in the bottom of the Meatus 
 Auditorius Internus. 
 
 Of thefe Branches, fmall Filaments pafs through the Macula 
 Cribrofa in the Inferior Foffula of the Meatus Auditorius Inter- 
 nus, to the Alveus Communis or Sacculus Vcftibuli. 
 
 A fmall Branch goes through another Cribiiform Hole in the 
 Inferior Foffula, to the Ampulla of the Pofteiior Membranace- 
 ous Semuircular Canal. 
 
 A Branch larger than any of the former, enters the Pofterior 
 Hole in the upper Foffula of the Meatus Internus, to be dil'perfed 
 ,upon the Ampullae of the Superior and Exterior Membranaceous 
 Canals. 
 
 The Nerves, after reaching the Sacculus Veftibnli and the 
 different Ampullae, are fpread out upon them, as in the Cochlea, 
 
235 
 
 in the form of a Net-work, the Fibres of which, by degrees be- 
 coming pellucid, dilappear upon the beginning uf the Membra- 
 naceous Canals. 
 
 Portio Dura.— The Portio Dura feparates from the Portio 
 Moilis, at the bottom of the Meatus Auditorius Internus, and 
 enters the Canalis or AquaduBus Fallopii, by the anterioi Hole 
 in the upper FolTula at the bottom of the Meatus. 
 
 After getting into the Canal, it receives the retrograde Nerve 
 from the Second Branch of the Fifth Pair, which enters by the 
 Foramen Innominatum on the fore-fide of the Pars Petrofa. 
 
 It lends Twigs through Foramina in the Tides of the Aquedufl, 
 to the Maltoid Cells and to the Mufele of the Stapes. 
 
 A little before its exit from the AqueduSt in the Adult, but 
 at the outer end of it in the Foetus, it gives off a reflected Branch, 
 termed Chorda Tympani, which palfes between the long Pro- 
 celfes of the Malleus and Incus, and over the Membrana Tym- 
 pani. 
 
 The Chorda Tympani goes afterwards in a Filfure at the 
 outlide of the Euftachian Tube, and joins the Lingual Branch 
 of the Fifth Pair, foon after that Nerve has got out of the Cra- 
 nium. 
 
 In its pafl'age, it fupplies the Mufcles of the Malleus, and the 
 Membranes, See. of the Tympanum. 
 
 "The Portio Dura afterwards palfes out of the Aqueduft by 
 the Foramen Stylo-maftoideum, and is at firft lodged deep, being 
 lituated in a hollow behind the Parotid Gland. 
 
 Herttjt gives a fmall Occipital Branch, which fends Twigs to 
 the back part of the Ear, and terminates in the Oblique Mufcles 
 of the Head. 
 
 It fends a Branch to the Digaltric, and another to the Stylo- 
 hyoid Mufele ; gives off a Filament which joins the Auricular 
 Branch of the Inferior Maxillary Nerve, and goes to the fore- 
 part of the Ear; and is connect'd by another fmall Filament at 
 the under part of the Ear, wuh Branches of the Sympathetic 
 Nerve which run along the External Carotid Artery. 
 
 It alfo furnfhes Filaments to the Parotid Gland, and then per- 
 forates it, dividing into large Branches, which join, feparate, and 
 rejoin, different times, on the fide of the Face. 
 
 This Plexus is expanded in fuch a manner as to con ftitute what 
 has been called by fome the Pes Anferinus, and is divided into 
 the following fets of Branches, viz. 
 
 The Temporal Branches , which afeend upon the fide of the 
 Head, to be dilfributed upon the Temple ; fome running over, 
 others under.. he Branches of the Temporal Artery, and forming 
 feveral joinings with the Frontal Branches of the firft part of the 
 Fifth Pair of Nerves : 
 
 The Superio - Facial Branches, which are difperfed upon the 
 Orbicularis Ocuii Mufele, and the parts in general about the 
 
236 
 
 outer angle of the Eye, communicating in various places above 
 and below the Orbit, with the firft and fecond Branches of the 
 Fifth Pair : 
 
 The Middle Facial Branch, or the Great Facial Nerve, which 
 runs acrufs the Maffeter Mufcle, and divides into many 
 Branches, to be difperfed upon the Cheek, and fide of the Nol'e 
 and Lips. 
 
 They are connected with the Branches of the Superior Facial, 
 and near the coiner of the Mouth, with others of the fecond 
 and third parts of the Fifth Pair. They have likewife fome 
 communications with deep Branches of thefe two Nerves which 
 pafs outwards between the Maffeter and Buccinator Mufcles. 
 
 The Inferior Facial Branches, which pioceed along the fide of 
 the under Jaw, to be difperfed upon the parts covering it, and up- 
 on the Under Lip ; and connefl themfeives with fome of the 
 Middle Facial Branches, and with others belonging to the third 
 part of the Fifth Pair : 
 
 The Defcending, or Subcutaneous Cervical Branches, fome of 
 which run forwards under the Lower Jaw, and others down- 
 wards, near the External Jugular Vein, to the Superficial Muf- 
 cles, and to the Integuments at the fide and upper part of the 
 Neck, where they form communicatioHs with the Infeiior Facial 
 Branches, and with diffeicnt Branches of the upper Spinal Cer- 
 vical Nerves. 
 
 The Eighth Pair arifcs from the Medulla Oblongata, at 
 the f.des of the Bales oi the Corpora Olivaria, and confilt in each 
 fide, of the Nervus Gloffo phtryngeus, and Pars Vaga. 
 
 The Glosso-PharyNglus is the IlnallerAf the two, being 
 only a little fupeiior in lize to one of the Nerves of the Fourth 
 Pair. 
 
 The Pars Vaga comes off immediately under the former, and 
 is competed of l'everal feparated Fafciculi, which are foon col- 
 lefled itno a iingie Cord. 
 
 The two Nerves, paffing outwards, go through the Bafe of the 
 Cranium, immediately befoie the end of the Lateral Sinus, by 
 the Hole common to the Occipital and Temporal Bone, and are 
 feparated from each other and from the Sinus by fmall Proceffes 
 of the Dura Mater. 
 
 The Glojfo P haryngeus, termed alfo Lingualis Lateralis, upon 
 its exit from che Ciani"m. lends a Branch backwards, which 
 joins the Digaftric Branch of the • oitiu Dura. 
 
 A little lower, >t gives off Branches, which, with others from 
 the Pharyngeal Branch of the Eighth Pa r, and from the Great 
 Sympathetic Nerve, Wm a Plexus which embraces the Internal 
 Carotid Artery, and afterwards fends Branches along the Caro- 
 tis Communis to the Heart. 
 
 Still lower, it gives Branches which communicate with others 
 belonging to the Pharyngeal Nerve, and go to the upper part of 
 the Pharynx arid to the Stylo-Pharyngeus Muffle. 
 
237 
 
 The Gloffo-Pharyngeus, after fending a Twig or two to the 
 Tonfil, to the upper part of the Pharynx, and Membrane of the 
 Epiglottis, divides into many Branches, which run partly to the 
 margin and partly to the middle of the root of the Tongue, fup- 
 plying, efpecially, the Papillae Majores and the parts in their 
 neighbourhood. 
 
 The Pars Faga,— upon emerging from the Cranium, frequent- 
 ly becomes a little increafed in diameter fir about an inch down- 
 wards ; forming what fome authors have termed its Ganglifortn 
 Enlargement. 
 
 It defcends in the Neck at the outer and back-part of the 
 common Carotid Artery, to which it is elolely united, being in- 
 cluded along with it in the fame common (heath of Cellular Sub- 
 ftance. 
 
 At the upper part of the Neck, it tranfmits a Branch to the 
 Pharynx ; and immediately afterwards, a large one to the 
 Larynx ; and near the top of the Thorax, it fends a Filament, 
 and fometimes two, to the Heart. 
 
 The Pharyngeus, — chiefly formed by the Pars Vaga, but partly 
 alfo by a Branch from the AccefTonus, is afterwards joined by 
 Branches from the Gloffo-Pharyngeus, and defcends obliquely 
 over the Internal Carotid Artery. 
 
 Near the origin of this Artery, it fends Filaments which join 
 others from the upper part of the Great Sympathetic, and creep 
 along the Common Carotid, to be united with the Carotid Ar- 
 tery. 
 
 Upon the middle of the»»Pharynx, it expands into a Gangli- 
 form Plexus, from which many fatal 1 Branches are fent ou., to 
 be dillributed upon the three Conftrififors of the correfponding 
 fide of the Pharynx ; one or two Filaments uniting ab ve with 
 the Gloffo-Pharyngeus, and others below with the Laryngeus Su- 
 perior. 
 
 The Laryngeus Superior, — defcends obliquely forwaids be- 
 tween the Caiotid Arteries and Pharynx ; and behind the origin 
 of the Carotids, is divided into a large Internal or Superior, and 
 a final! External or Inferior Branch. 
 
 The Internal Branch paffes forwards between the Os Hyoides 
 and Superior Cornu of the Thyroid Cartilage. 
 
 It divides into numerous Branches, fome of which go to the 
 Arytenoid Gland, and to the Oblique and Tranfverfe Arytenoid 
 Mufcles, and others to the Glandular Membrane of the Epiglot- 
 tis ; while the greater number and the lar elf of thei'e Branches 
 are dtiperfed upon the Glandular Membrane lining the upper 
 portion of the Larynx and parts adjacent. 
 
 The External Branch,— -which Scarpa confiders as more pro- 
 perly termed Pbaryngo Laryngeus, — is originally compofed of a 
 Branch from the Internal Laryngeal, and another from the Great 
 
233 
 
 Sympathetic ; and is conneXed by a Filament to the Pharyngeal, 
 and i'ometimes alfu by one to the Internal Laryngeal Nerve. 
 
 It imparts Twigs to ih Middle and Lower ConftriXors of the 
 Pharynx, and afterwards terminates in the fhyroid Gland and 
 inner part of the Larynx. 
 
 The Filament, lent from the Pars V.tga at the bottom of the 
 Neck, joins the Gieat Cardiac Bianeh of the Sympathetic Nerve 
 in the upper part of the Thorax, to be difperfed upon the Heart, 
 
 The Ninth Pair, — frequently termed Linguales, and fome- 
 times Linguales MeJii ,■ — arile from the under and lateral parts of 
 the Coipora Pyram dtlia, on the foie fide of the Medulla Ob- 
 longata, by numerous Filaments which are culleXcd into Faf- 
 ciculi. 
 
 They pafs out at the Superioi Cond . 1 rid Foramina of the Oc- 
 c'pital Bone, after which they adhere, for fome way, to the 
 Eighth Pair, by Cellular Spbdtnce. 
 
 A little below the Cranium, each of the Trunks of tills Pair 
 of Nerves s conjoined by a crofs Branch with the Suboccip tal 
 Nerve, or with an Arch which conneXs that Nerve and the Full 
 Cervical together. 
 
 The Trunk then depends between the Internal Jugular Vein 
 and Internal Carotid Artery, and at the toot of the Occipital Ar- 
 tery erodes over bo'b Carotids to its place of deft nation. 
 
 Where it begins to crofs oyer the Carotid?, it fends down a 
 Branchof considerable ftze, termed Defcend.ens Noni. 
 
 Til Defcendens Noni paffes down a certain length along' with 
 the common Catolul Artery, and, in its courfe, furn Ihes 
 Branches to the upper ends of the Omo-hyoid and Sterno-thyroid 
 MnlcJes, after which it unites with Branches fr. m the Fit ft and 
 Second, ar.d with (’mail Filaments from the Second and Third 
 Cetvical Nerves, forming an Arch, from which I. hg and (lender 
 Twigs go to the under portions of the Sterno-thyroid, and to the 
 Omo-hyo d and Sterno-hyoid Mufcles. 
 
 The Ninth Pair paffes afterwards behind the Facial Trunk 
 and Temporal Veins, or the Trunk formed by thefe, and over the 
 root of the Facia! Artery,— fending a Nervous Twig to the Hyo- 
 thyioid Mufcle. 
 
 Upon the Hyo-gloflus Mufcle, the Trunk of the Nerve is 
 fpread into a great number of Branches, which go to the middle 
 of the Tongue, and terminate chiefly in its Flcfhy parts ; a Twig 
 extending as far as the Genio-hyoid Mufcle, and two or fome- 
 times only one Filament anaftomofing fvith the Lingual Branch 
 of the Fifth Pair. 
 
 The Great Sympathetic Nerve, — obtaining its name 
 from its numerous Connexions with moft of the other Nerves of 
 the Body,- — ;s either formed originally by the reflected Branch 
 from the fecond of the Fifth Pair, and by one or two and fome- 
 times three fmall Filaments, fent down from the Sixth Pair while 
 
239 
 
 in the Cavernous Sinus ; or, according to the opinion of feme 
 Authors, the Sympathetic fends off thefe fmall Nerves to join the 
 Fifth and Sixth Pairs. 
 
 Upon the Surface of the Internal Carotid Aitery, while in the 
 Carotic Canal, the Branches of the Fifth and Sixth Pairs and 
 Great Sympathetic miking this connexion, are pal, y and tender, 
 and foim a Plexus which furrounds the Carotid, and from which 
 the Trunk of the Sympathetic is mod frequently confidered as 
 being fent out. 
 
 At er efcaping from the Carotic Canal, the Trunk which is 
 of fmall fze, is clolely connefied, for a fhort fpace, with the 
 Trunks of the Eighth and Ninth Pairs; and, fepara.ing from 
 thefe, it expands into a large Ganglion, — termed Ganglion Cer-vi- 
 cale Supeiius, — of a long oval form, and licuated oppolite to the- 
 Second Cervical Vertebra. 
 
 From this Ganglion, the Nerve comes out very little increafed 
 in fize, — and delcends on the anterior Vertebral Mufcles of the 
 Neck, — behind the Eighth Pair of Nerves, with which, and 
 with the Carotid Ai tery, it is connefled by a Sheath of Cellular 
 Subftance. 
 
 At the under part of the Neck, and nearly where the Inferior 
 Laryngeal Artery turns over towards the Larynx, ihe Sympa- 
 thetic form, another Ganglion, termed by fume Authors Cer<ui- 
 c ale Medium and by others Cernjicale lnferius. 
 
 The Ganglion Medium is fomewhat nmilar in fhape and fize to 
 the Ganglion Superius ; though it varies coniideiably in thefe 
 rel'pe£ts in diffeient Subjefts. 
 
 From this Ganglion, principal Branches are fent down, one of 
 which, larger than the reft, and considered as the continuaiion of 
 the Trunk, turns outwards between the Inferior Laryngeal and 
 Vertebral Arteries to another Ganglion. 
 
 This third Ganglion, — is placed at the head of the firft Rib, 
 and is termed by lome Authors Ganglion Cer-uicale lnferius , or 
 Imum, while others coniider it as the firft of the Thoracic Gan- 
 glia^ 
 
 The Cervical part of the Great Sympathetic is connefted with 
 other Nerves, and difperfed upon diffeient parts by the following 
 Branches, viz. 
 
 One or two fhort, but thick Branches, which corineS the be- 
 ginning of the Superior Ganglion with the root of the Subocci- 
 'pital Nerve : 
 
 Oae or two Pulpy Nerves, which run forwards behind the In- 
 ternal Carotid Artery, and divide into many others. Thele, to- 
 gether w.th Filaments from the Gloffo-pharyngeus, »>rm a 
 Plexus which fends Branches to the Ganglform Expanlion of the 
 Pharyngeus, and afterwards embiaces. the external Carotid 
 Artery, fending PJexufes of Filaments along its different 
 Branches : 
 
240 
 
 One or two other Toft Nerves, going behind the Internal Caro- 
 tid, and with a Branch of the Laryngeus Interims of the Eighth 
 Pair, forming the Laryngeus Externus : 
 
 Thick (hort Roots connecting the Firit, or Conjugation of the 
 Firit and Second Cervicals, with the fuperior Ganglion of the 
 Spmpathetic Nerve. 
 
 From the Superior Ganglion alfo, are fent offfmall Branches, 
 which uniting with Filaments from the Laryngeus Superior, 
 form the Rumus C.ardiacus Supremus, or Superficial is Cordis. 
 
 The Superficial Cardiac Nernje of the Sympathetic, in the 
 Right Side, d vides into Branches at the bottom of the Neck, 
 which fend a Filament or two along the Inferior Laryngeal Ar- 
 tery to the Thyroid Gland and afterwards unite with the Superfi- 
 cial Cardiac Nerve of the Eighth Pair before the Subclavian Ar- 
 tery, and with the Laryngeal Nerve behind it.— In the left fide, 
 it terminates in the Cardiac Plexus of Nerves. 
 
 From the Second, Third, and Fourth Cervical Nerves, an 
 equal number of Cords defcend behind the Scaleni and ReXus 
 Major Mufcle, to the middle Ganglion of the Great Sympa- 
 thetic. 
 
 From the oppofite fide of the Ganglion, Branches are fent 
 down, which join and form the Ner-uous Magnus Projundus ; 
 others are fixed to the Superficial Cardiac and to the Recurrent of 
 the Eighth Pair the relt go partly over and partly beh nd the 
 Subclavian Artery, to the Inferior Cervical, and to the firft 
 Thoracic Ganglion. 
 
 Nervi Accessorii ad Par Octavom, — The Acceffory 
 Nerves arile by fmall Filaments from the lateral Parts of the 
 Medulla Oblongata and upper portion of the Spinal Marrow. 
 
 The Filaments from the Spinal Marrow come off between the 
 anterior and polterior Bundies of the Cervical Nerves, — the firft 
 of them frequently extending as far as the /pace between the 
 Sixth and Seventh Pairs. 
 
 The different Filaments unite by degrees into their refpeXive 
 Trunks, and often have connexions while within the Dura 
 Mater, with one or two of the Bundles of the upppermoll Spinal 
 Nerves. 
 
 The Trunk of the Nerve paffes out, on each fide of the Cra- 
 nium, in company with the Nerve of the Eighth Pair; but forms 
 no part of that Nerve, being included in its own peculiar Sheath 
 received from the Dura Mater. 
 
 After perforating the Cranium, it feparates from the Eighth, 
 and defcemls obliquely outwards through the Sterno-maftoid 
 Mufcle to the Shoulder. 
 
 At its exit, it fends off a Branch, termed by fome Ramus Mi- 
 nor, (the Trunk itf'elf being then called Ramus Major), which 
 aflifts in forming the Pharyngeal Nerve ; and gives another, 
 
241 
 
 (mailer than the former, to be conne&ed to the Pars Vaga of the 
 Eighth Pair. 
 
 At the rore-part of the Sterno-maftoid Mufcle, it is joined by 
 an Arch to the Suboccipital, and frequently by another to the 
 Firft Cervical Nerve. 
 
 In its paffage through the Sterno-maftoideus, it fends feveral 
 Branches to the fubftance of that Mufcle, and terminates at 
 length in the Trapezius. 
 
 .OOOOOOOO -.K-OOOOOOOO' 
 
 SPINAL MARROW , 
 
 AND 
 
 ORIGIN OF THE SPINAL NERVES. 
 
 THE Spinal Marrow is the continuation of the Medulla 
 Oblongata, and obtains its name from being contained in the 
 Olfeous Canal of the Spine. 
 
 It is inverted by the fame Membranes which cover the Brain, 
 and has an additional partial Involucrum from the Ligamentous 
 Membrane which lines the Bodies of the Vertebrae, and which 
 has been already taken notice of in the defcription of the Liga- 
 ments. 
 
 On the inner fide of the Ligamentous Lining, the Dura Mater 
 is fituated, which paffes out of the Cranium b^' the Foramen 
 Magnum Occipitis, and forms a Cylindrical Sheath which loofe- 
 ly envelopes the Spinal Marrow, and extends as far as the Os 
 Sacrum. 
 
 It is more elaftic than the Dura Mater of the Brain, and there 
 by admits more readily of the different motions of the Spine. 
 
 At its egrefs from the Cranium, it is int imately connefled to 
 the beginning of the above-mentioned common Ligamentous 
 Lining, and is alfo united with the Pericranium at the edge of 
 the Foramen Magnum of the Occipital Bone. 
 
 Below the Firft Vertebra of the Neck this inornate connexion 
 between the Dura Mater and inner Ligament of the Vertebrae is 
 difcontinued ; a Celiular Fatty, and Slimy Subjiance, which fur- 
 
 Vol. II. X 
 
242 
 
 rounds the Dura Mater throughout the reft of the Canal, being 
 interpoi'ed between the Membrane and the Ligament. 
 
 The Dura Mater is only in coniadt with the Tunica Arachnoi- 
 dea, and this alfo only in contatt with the Pia Mater, and lying 
 lo loolefy over it as to be feparated (torn it with facility through 
 the whole length of the Spine. 
 
 The Sj inal Marrow, rke the Brain, confifts of a cortical and 
 Medullary Subftnnce, but d'ffers in this rel’peft, that the Cineri- 
 tious Matter is placed within the other. 
 
 Upon the Sutface of the Spinal Marrow, while lying in its 
 natural fituation, many tranfverfe Wrinkles or Folds are ob- 
 ierved, which allow it to be extended in the motions of the Ver- 
 tebias. 
 
 It is a little flattened on its anterior and pofterior Surfaces, and 
 is larger near the under part of the Neck, and at the top of the 
 Loins where the great Nerves of the Extremities are fent off, than 
 in the other parts of the Spine. 
 
 It is divided into two lateral Portions or Cords, which are fepa- 
 rated from each other externally by an anterior and pofterior Fif- 
 fure continued from the Medulla Oblongata; and each of the. 
 lateral Portions is in fome meafure fubdivided bv a fuperficial 
 Furrow into a larger anterior and f'mall pofterior Cord. 
 
 The lateral Portions are firmly united together by fine Cellu- 
 lar Subftance, but may be feparated from each other before as 
 well as behind, — without lacerating either, — to near their mid- 
 dle, where they are conne£fed by a Layer of Cineritious Mat- 
 ter which paftbs from the one Cord into the other. 
 
 When the Medulla Spinalis is divided tranfverfely, the Cine- 
 ritious Subftance is obferved to have a Cruciform appearance, 
 correfponding with the Cords of which it is compofed. 
 
 The Body of the Spinal Marrow defeends as far as the Second 
 Vertebra of the Loins, and terminates there by a Conical point, 
 which is concealed by Fafculi of Nerves. 
 
 Each of the lateral poitions of the Spinal Marrow fends off 
 from its anterior and pofterior parts, flat Fafciculi of Nervous 
 Filaments, wltich are placed oppofite their fellows on the other 
 fide. ^ 
 
 Several of the Fafciculi of the Cervical Nerves detach Fila- 
 ments to thole immediately above or below them ; and the fame 
 thing is occafionally obferved of fome of the Bundles of Dorl'al 
 Nerves. 
 
 The anterior and pofterior Fafciculi perforate the Dura Mater, 
 from the inner part of which each Fafciculus is furnifhed with a 
 proper Sheath, and is continued within it, the Sheaths conne£Kd 
 by Cellular Subftance only, till they get between the Vertebrae. 
 
 Between the anterior and pofterior Fafciculi or Spinal Neives, 
 and between the Tunica Arathnoidea and Pia Mater, a fmall 
 Ligamentous Cord termed Ligamentum Dcnticulatum , is fituated, 
 
245 
 
 which is attached to the Dura Mater, where that Membrane 
 comes out from tile Cranium and accompanies the Spinal Mar- 
 row to its inferior extremity. 
 
 It adheres ' >y Cellular Subllance to the Pia Mater, and fends 
 off f orn its oppofite fide lYnall Cords, in the form of Denticuli , 
 which carry the Tunica Arachnoidea along with them, and run- 
 ning more or iefs in a tranfverfe d:re£Lon, are fixed, each by 
 minute Fibres to the Dura Mater, in the Interflices of theFafci- 
 culi. 
 
 The Ligamentum Denticulatum of the oppofite fides incorpo- 
 rate with he Pia Mater at the inferior extremity, or Conical point 
 of the Spinal Mairow, and forma Ligamentous Filament which 
 perforates the under end of the Dura Mater, and is fixed by 
 fimail Fibres to the Membranes covering the Os Coccygis, in 
 the manner the Denticuli are fixed to the Dura Mater. 
 
 It was termed by Come Authors Ligamentum Pia: Matris. It 
 was considered by the Ancients as the Fortieth Pair of Nerves, 
 and was alio called Ner-vus Imparus Sacrus. 
 
 It affifts in preventing the Spinal Marrow and the tender origin 
 of the Nerves from being overftretched. 
 
 Having got between the Vertebrae, each of the pofterior Bun- 
 dles forms a Ganglion, from the oppofite end of which a Nerve 
 comes out, and is immediately joined by the anterior Bundle, 
 thus conftituting the beginnings of the Trunks of the Spinal 
 Nerves. 
 
 The Nervous Cords fent out from the Spinal Marrow, after re- 
 ceiving their coverings from the Dura Mater, become confidera- 
 biy larger than the Fafciculi which form them ; as has been 
 already obferved in the general defcription of the Nerves. 
 
 As foon as the Spinal Nerves emerge from between the Verte- 
 brae, each lends Branches backwards to theMufcles near the Spine, 
 and others forwards to join the Great Sympathetic Nerve, while 
 the Trunk is continued outwards to its place of deftlnation. 
 
 The Spinal Nerves are diftingui fned on each fide, by numbers, 
 aceoiding to the Bones under which they pafs ; Thirty Pairs are 
 meft commonly enumerated. — One going under the Head, and 
 termed Suboccipttal — Seven p fling under the Vertebra; of the 
 Neck ; — Twelve under the Dorfal ; — Five under the Lumbar Ver- 
 tebrae ; an , — Five under the pieces which originally compofed 
 the O, Sacrum. 
 
 The Fafciculi which form the Cervical Nerves are fhart, run- 
 ning nearly in a ftraight direflion from their origin to the Inter- 
 vertebral Holes. Thofe which form the Dorfal Nerves are long- 
 er than the former, and run more obliquely downwards ; and 
 thofe which form the Lumbar and Sacral Nerves are very long and 
 run Hill more obliquely downwards, till at length the undennoft 
 ef them become nearly longitudinal. 
 
244 
 
 The fize cf the Fafculi correfponds with that of the Nerves 
 which they go to form. — The Fafciculi of the four loweft Cervi- 
 cal and fii it Dorfal, are large and broad, giving origin to the 
 Gieat Nerves which fupply the Superior Extremity Thofe of 
 the Back are much more [lender, while the Fafciculi of the Loins 
 and the two upper Sacral ones are of great fize, to form the 
 very large Nhrves which run to the Lower Extremity. 
 
 The Lumbar and Sacral Fafciculi, while included in the Dura 
 Mater, form a Bundle of Cords, termed Cauda Equina, from 
 the relcmblance it has to the Tail of a Horfe ; efpecially when 
 the FibrilTae of the Nerv.es are unravelled by feparating them from 
 each other. 
 
 The Fafciculi perforate theDuia Mater, nearly oppofite to the 
 parts where they pais through the Vertebrae, — of courfe the 
 Nerves of the inferior parts of the Spinal Marrow emerge from 
 the Spine, confide! ably lower than their different origins. 
 
 Blood-Vessels of the Spinal Marrow. — The Arte- 
 ries of tlie Spinal Marrow conlilt of Anterior and Pofterior Spi- 
 nal An eries, and of many additional Branches communicating 
 with o.liers from the adjacent Vtlfels. 
 
 The Anterior Spinal arteries arife, one on each fide, from the 
 Vertebrals, near where thel'e join to form the Balilar Artery. 
 
 Upon the beginning of the Spinal Marrows they generally 
 unite into a common Trunk, winch defeends- in that depreffion 
 on the Anterior Surface of the Medulla, whereby it is diftin- 
 guifhed into two Lateral Portions, — and the Artery continues 
 nearly of the fame fize throughout, in confequence of additions 
 it receives from the neighbouring Arteries. 
 
 In the Neck, it communicates with the Vertebral Thyroid, and 
 Cervical Arteries, by Blanches which pafs through the fame 
 Holes with the Nerves. 
 
 In the Back, it receives Branches from the Intercoftal, and in 
 the Loins from the Lumbar Arteries; all of which alfio go 
 through the Intervertebral Holes. 
 
 It terminates at the under end of the Spinal Marrow; the 
 Cauda Equina being fupplied by Branches from the Internal 
 Iliac Artery, which enter through the anterior and pofterior 
 Holes of the Os Sacrum. 
 
 The i ojlerior Spinal Arteries , — arife commonly from the infe- 
 rior Arteries of the Cerebellum, and frequently from the Trunks 
 of the Vertebral Arteries within the Cranium. 
 
 They are equal in length to the tormer Artery, but confidera- 
 bly inferior to it in lize, and continue feparate through the whole 
 of the r courfe. 
 
 They have conftantly a Serpentine appearance, and foim fre- 
 quent Inofcul tions with each other, and with Arteries, the 
 Branches of which communicate with the anterior Spinal Ar- 
 tery. 
 
245 
 
 The Arteries of the Spinal Mirrow are divided into minute 
 Branches, which are difperfed upon its fubftance, upon the Mem- 
 branes which inclofe it, and alfo upon the fubftance of the Verte- 
 brae and upon the origins of the Nerves. 
 
 The Veins of the Spinal Marrow accompany their Arteries, 
 and afterwards terminate in the Sinus Venoii of the Spine. 
 
 The Sinus Venofi conlift of one on each fide, which runs exte- 
 rior to the Dura Miter, being chiefly lodged in the Ligamen- 
 tous Membrane which lines the fore and lateral parts of the Ver- 
 tebral Canal. 
 
 They extend from the Foramen Magnum of the Occipital 
 Bone, to the under end of the Os Sacrum, and are fo irregular 
 on their furface, and fo much divided and fubdivided within by 
 the openings of Veins, as in many parts to have the appearance 
 of Cells. 
 
 At the different Vertebrae, they are conjoined by crofs Branch- 
 es, wnich have a Semilunar form, like the furface of the Bones 
 which furround them. 
 
 They communicate at their Superior extremity with the Occi- 
 pital and Lateral Sinufes, and lend numberlel's Branches out- 
 wards, wh ch open into the Veins the Arteries of which anafto- 
 mofe with thofe of the Spinal Marrow. 
 
 Nerves of the Neck and Superior 
 Extremity. 
 
 Nervus Accessorius. — The AccefTory Nerve belongs in 
 fome refpects to this Clais of Nerves ; — >ut having part of its 
 origin .ithin the Head, and from its palTing out with one of the 
 Cerebral Nerves, it has been already defer: bed along with thefe. 
 
 Suboccipital Nerves. — T hefe we. e formerly called Tenth 
 Fair of the Head, and by many at prelent are termed Firfi of the 
 Neck. 
 
 They arife, on each fide, from the beginning of the Spinal 
 Marr .w, by an Anterior and Potterin' Fafciculus, like the reii 
 of the Spinal Nerves ; and, like thefe alfo, they have their Gan- 
 glia where they pafs out beiween the Bones. 
 
 They perforate the Dura Mater immediately under the en- 
 trance of the Vertebral Arteries, and pafs forwards under them, 
 and over the rranfverfe Procefles of the Atlas. 
 
 They afterwards appear in the fore-part of the Neck, and are 
 each connected above by an Arch to the root of the Ninth Pair, 
 and below by a ftmilar Arch to he Firft Cervical Nerve. 
 
 Anteriorly, they are joined by one or two ihorl Branches to 
 the upper Ganglia oftheGreat Sympathetic Nerve. 
 
 They afterwards divide into Branches, which are diftributed 
 upon the Reibi and Obliqui Capitis, and upon fome of the Deep 
 Extenfor Mufcles of the Head. 
 
 Vol. II, X 2 
 
246 
 
 The First Cervical Nerve, — omes out, on each fide, be- 
 tween :iie Atlas and Second V ... i>r;, f ihe Neck, and immedi- 
 ately fplits nto two parts j the i it of which palfe- forwa; ds un- 
 der t ht tranl'verl'e Procefs f he Atlas., and is joined by an Arch 
 with the Nei vus Aeeelloi ius. and by Brandies with the Ninth 
 Pair: it is alfo roi, nieiSbed by a loft Ganghform pellucid root with 
 tl.e ppei Gang! n of the Symmithfe ir Nerve, lending a Branch 
 downwards, to be fixed to the lecond Cervical rNerve, and alfo 
 fmall Branches to the Mufcles connected with the fore part of 
 the Vep tbrte. 
 
 The othei, which is the principal part, goes backwards, and, 
 after fending Blanches to the Extenfor Mufcles of the Head and 
 Neck, perforates thele, and forms the Proper Occipital Nerve. 
 
 The Occipital Nerve afcends upon the Head with the Artery of 
 that name, and terminates upon the Mufcles and Integuments on 
 the upper and back-part of the Head; fome of its Filaments 
 anaftpmofin.: with others belonging to ihe Fil'd Branch of the 
 Fifth, and Portio Ultra of the Seventh Pair. 
 
 The Second Cervical Nerve, — fter efcaping from be- 
 tween the Bones, gives off a Branch, which perforates the Muf- 
 cles connected to the fore and lateial parts of the Vertebise, and 
 joins the middle Ganglion of the Sympathetic Nerve. 
 
 It fends another Branch of coniiderable fize downwards to the 
 Trunk of the Third Pair. 
 
 It fends feveral Branches to the Sterno-maftoid Mufcle, behind 
 which it is connefled by an Arch, and ffcill farther out by a Fila- 
 ment, w th the Nervus AccefTorius. 
 
 It is afterwards divided into feveral Branches, one of which 
 partes downwards fome way upon the External jugular Vein, 
 and, toge'her with a Branch from the Fil'd Cervical, forms an 
 Arch with the Defcendens of the Ninth Pair. 
 
 It gives off a fmall root which is united with others in the for- 
 mation of the Diaphragmatic Nerve. 
 
 A Large Branch comes out from it behind the Sterno-Maftoi- 
 deus, which, turning over this Mufcle, fends off the following 
 Nerves, viz. 
 
 "The. Inferior Cutaneous Nerve of the Neck, which partes for- 
 wards to the parts under the Lower Jaw : 
 
 The Middle Cutaneous Nerve, which runs towards the angle of 
 the Jaw. 
 
 The Great Poferior Auricular Nerve, which furnifhes an ante- 
 rior Branch to the under part of the Ear, and a pofterior Branch 
 div’ding into many others which go to the back-part of the Ear 
 and Temple. 
 
 The Cutaneous and Auricular' Nerves are difperfed upon the 
 Piatyfma Myoides, Integuments of the fide of the Neck and 
 Head, the Parotid Gland, and External Ear and have leveral 
 Communications with the Poitio Dura of the Seventh Pair. 
 
2-n 
 
 The remainder of the Second Cervical is diftributed upon the 
 L'V’ior Scapulas, and the Extenlor Mufcles of the Neck and 
 
 Head 
 
 The Timo Cervical Nebve, — afier emerging from be- 
 tween the Ve, rebrae, lends down a Branch to the T.unk of the 
 Fourth Cervical, a. id another Branch which forms the piincipal 
 root of the Diaphragmatic Nerve. 
 
 A 1 Third. Branch perforates the Mufcles on the fide of t lie 
 Vertebrae* and joins the middle Ganglion of the Sympathetic 
 Nerve. 
 
 A Small Filament conne&s a Third Cervical with the De- 
 feenden.-. of the Ninth Pair. 
 
 The Nerve is afterwards divided into External and Internal 
 Branches. 
 
 The External Branches form Anaftomofes with the Nervus 
 Acceffonus, near the upper part of the Scapula ; wh le the In- 
 terior, after furnifhing Twigs to the Jugular Glands, are dif- 
 perf’ed by feverai large Branches upon the Mufcles and Integu- 
 ments at the under part of the Neck, and upper part of the 
 Shoulder. 
 
 The Fourth Cervical, — fends a Branch behind the Muf- 
 cles (ituated on the fore and lateral parts of the Cervical Verte- 
 brae, to the middle Ganglion of the Sympathetic Nerve. 
 
 It is connefted by one, and fometimes- by two Filaments to the 
 Diaphragmatic Nerve. 
 
 It gives Twigs to the Jugular Glands and deep Mufcles of 
 the Neck, and at the outer edge of the anterior Scalenus, joins 
 the Fifth Cervical Nerve. 
 
 The Fifth Cervical, — is united with the Fourth into a 
 Common Trunk, which, after running a little farther out, joins 
 the Sixth Cervical Nerve. 
 
 The Sixth Cervical, — joins the Seventh behind the Clavi- 
 cle ; and to the Seventh, the Firft Dorfal Nerve is added over the 
 Firft Rib. 
 
 
 The Four Inferior Cervicals and Firft Dorfal Nerve are of great 
 fize, — efpecially the three intermediate Nerves. 
 
 They pafs out between the Scalenus Anticus and Medius,— ■ 
 and afterwards run between the Subclavian Mufcle and Firft Rib, 
 at the ou ef fide of the Subclavian Artery, to the Axilla. 
 
 In the Axilla, they feparate, unite, and fepurate again, form- 
 ing an irregular Plexus, termed Axillary or Brachial , — which 
 furrounds the Axillary Artery. 
 
 The Axillary Plexus feuds Branches to the Subfeapularis, Te- 
 res Major, and Latiflimus Doni, and furnifhes the External 
 Thoracic Nerves which accompany the Blood- vefiels of that 
 name to the Peftural Mufcles and Integuments. 
 
 The Plexus afterwaids divides into Nerves, moft of which are 
 of great fize, to fupply the Superior Extremity. — They are as 
 follow. 
 
The Scapularis, — which commonly arifes from the com- 
 bination of the Fourth and Fifth Pairs, and extending outwards, 
 runs through the Semilunar Arch in the upper edge of the Sca- 
 pula, afterwards defending between the root of the Spine and 
 Head of the Scapula. 
 
 It furnifttes Blanches to the Supra-Spinatus, and is afterwards 
 confumed upon the Infra- Spinatus Mulcle. 
 
 The Articulakis, — which arifes, like the former Nerve, 
 from the Trunk common to the Fourth and Fifth Cervicals. 
 
 It finks deep in the Axilla, and getting between the under 
 edge of the Subfcapularis, and Infertions of the Teres Major and 
 LatifTiinus Dorfi, it follows the courfeof the Pofterior Aiticular 
 Artery round the Body of the Os Humeri, immediately below 
 the Articulation. 
 
 It fends Branches to the Teres M ; nor, and fome Twigs to the 
 Ligament of the Joint ; but is chiefly difperfed upon the Deltoid 
 Mulcle. 
 
 The Nervus Cutaneus, — which arifes from the Trunk 
 common to the 1 a It Cervical and Fill Doifal Nerve j but is 
 chiefly formed by Fibrillae from the latter. 
 
 It runs down at the inner and fore-part of the Arm, near the 
 Radial Nerve. 
 
 It ibmetim.es gives a fmall Branch to the upper part of the Co- 
 raco-brachialis and Biceps ; and, farther down, it gives others 
 to the Integuments and Coats of the Blood-velfels. 
 
 About the middle of the Aim, it fplits into two Branches, an 
 Internal and External. 
 
 Th a Internal Branch, which is rather the finaller of the two, 
 paffes before the Balilic Vein to the inner part of the Elbow, 
 ■where it divides into Branches, two of which, larger than the 
 reft, turn obliquely over the Heads of the Flexor^ of the Hand, 
 to be difperfed upon the inner and back-part of the fore-arm. 
 
 The External Branch divides into feveral others, behind the 
 Median Balilic Vein, which delcend on the anterior and Ulnar 
 fide of the Fore-arm, as far as the Wrift. 
 
 They pafs partly over and partly under the Subcutaneous 
 Veffels ; furnifhing Twigs to thefe, and vanilliing in the Integu- 
 ments. 
 
 Befides the Nervus Cutaneus, there is another termed Cutane- 
 us Minor of Wrisberg, which, like the reft of the 
 
 Nerves of the Superior Extremity, takes its origin from the Ax- 
 illary Plexus ; but is more particularly connected with the Ul- 
 nar Nerve. — It is confiderably inferior in fize to the Nervus Cu- 
 taneus. 
 
 It foon feparates from the Ulnar, running afterwards between 
 it and the inner fide of the Arm. 
 
 A little below the Axilla, it fplits into two Branches : 
 
249 
 
 The fmaller, turning to the pofterior part of the Ann, is divi- 
 ded into Filaments which are chiefly difperled upon the Triceps 
 and its Integuments. 
 
 The larger Branch defcends at the inner edge of the Triceps, 
 and vanilhes upon the under end of that Mul'cle and Skin of the 
 Elbow. 
 
 The Musculo-Cutaneus, called alfo Perfcrans Caserii, 
 — which coniifts of Fibrillse from almoft all the Nerves entering 
 the Plexus. 
 
 The Cord formed by thefe perforates, obliquely, the upper 
 part of the Coraco-brachialis, to wh ch it gives Branches. 
 
 It afterwards paffes between the Biceps and Brachiahs Inter- 
 ims, furn idling Branches to both. 
 
 At the Elbow, it gets to the outfide of the Tendon of the Bi- 
 ceps, and runs behind the Median Cephalic Vein. 
 
 From thence it defcends in the Fore-arm, between the Supina- 
 tor Longus and Integuments ; furnifliing Brandies to the latter, 
 as far as the root of the Thumb and backof ihe Hand. 
 
 The Spiral, or Spiral-Muscular Nerve, — which is 
 apparently formed by all the Nerves entering into ,he Axillary 
 Plexus, and when the Sheaths of the Nerves are flit open, is found 
 to be compofed of Fibril'* from each of the Trunks, excepting 
 from that of the Firft Dorfal. 
 
 It is rather larger than any other Nerve of the Superior Ex- 
 tremity, and is dillinguifhed by its Spiral direftion. 
 
 It is at firft fituatec! between the Axillary Artery and the Ul- 
 nar Nerve, and palfes obliquely downwards between the two 
 Heads of the Triceps Extenfor Cubiti, and afterwards behind 
 the Os Humeri, to the outfide of the Elbow. 
 
 From thence it p.oceeds among the Mufcles of the Radial fide 
 of the Fore-arm, as far as the Hand. 
 
 While pafling behind the Os Humeri, it gives feveral Branch- 
 es of confiderable fize to the different Heads of theTiiceps; 
 fome of th.m accompanying the Branches of the Arteria Spiralis, 
 and terminating on the Heads of the Extenfors of the Hand. 
 
 Immediately behind the body of the Os Humeri, it tranfmits a 
 Subcutaneous Branch, which is d i Hi i bu ted upon the Mufcles 
 and Integuments on 'he pofterior part of the Fore-arm, anaftomo- 
 fing at laid with the Nerves on the back-part of the Hand. 
 
 The Trunk of the Nerve having arrived at the Elbow, is lod- 
 ged in a F: flu re between the Brachialis Internus and Radial Ex- 
 tenfors of the Carpus, and there gives off other Branches to the 
 Extenfors ot the Hand, and to the Supinator Mufcles. 
 
 At the Head of the Radios, the Trunk of the Nerve divides 
 in'o two nearly equal Branches, — the Superficial!; and Profun- 
 dus. 
 
 The Superficial!;, continued almoft ftraight from the Trunk, 
 immediately tranfmits a Branch to the Extcnfores Radiales and 
 
250 
 
 Supinator Longus, and then defcends at the inner edge of this 
 Mufcle along with the Radial Artery. 
 
 A little below the middle of the Radius, it erodes between 
 the Tendon i f the Supinator and Extenlores Radiales, and is 
 fubdivided into a Volar and Dm fal Branch. 
 
 The Volar Branch, after fending Twigs to the Annular Li- 
 gament, is diftributed to the Mufcles and Integuments of the 
 Thumb. 
 
 The Dorfal Branch is again fubdivided into numerous other 
 Branches, fome of which go to the Mufcles in the inerval of 
 the Metacarpal Bones of the Thumb and Fore-finger, a few Fi- 
 laments being diftributed to the Annular Ligament, while prin- 
 cipal Branches run one along each fide of the Foie and Mid-fin- 
 ger, and hkewil'e along the Radial fide of the Ring-finger. 
 
 The Ramus Profundus, after fending feveral Branches to the 
 Extenfores Radiales and Supinator Brevis, perforates the latter, 
 and gets to the back-part -of the Fore-arm. 
 
 Alter quitting the Supinator, it defcends under the Extenfor 
 Primi Internodii Pollicis and Extenfor Digitorum to the back of 
 the Hand. 
 
 In tin's courfe, it fends Branches to the different Extenfors of 
 the Thumb and Fingers, and at length degenerates into a (lender 
 Branch, which, at the Wrift, adheres clofely to the Annular 
 Ligament, where it has a Ganglilortn appearance, and is difper- 
 fed partly upon this Ligament and partly upon the Membranes 
 on the back of the Metacarpus. 
 
 The Median or Radial Nerve, — which comes from the 
 middle and lower part of the Plexus, is formed by Fafciculi front 
 all the Nerves which enter the Plexus, and is nearly of a fimilar 
 fize with the Spiral Newe. 
 
 Ii defcends in the Arm along the anter or furface of the Hu- 
 meral Artery, to which, and to the Deep Veins, it adheres firm- 
 ly by Cellular Subftnnce. 
 
 In this courfe, it does not give off any confiderahle Branches ; 
 — Twics, however, are lent from it to the Coats of the Adjacent 
 Veffels. 
 
 At the bending of the Elbow, it flips over the Tendon of the 
 Brachialis Interims, and perforates the back-part of the Pronator 
 Teres Mufcle. 
 
 It afterwards pnfles down between the Flexor Radialis and 
 Mufcuius Subl’mis, and goes in the middle of the interval of 
 the Radial and Ulnar Artery in its way to the Hand. 
 
 When it approaches the Fore arm, it tranfmits Blanches to 
 the Pronator Teres and Integuments near that Mufcle. 
 
 In the Flexure of the Arm, it fumithes Branches to the Pro- 
 nator, Flexor Radialis, and Flexor Sublimis, and an Interotfe- 
 ous Branch which, in fome Subjefts, receives an addition from 
 the Spiral Nerve. 
 
251 
 
 The Interojfecus Nerve gives Branches to the Flexor Longus 
 Pollicis, and ro t .e Flexor Profundus Digitorum, defcends upon 
 th interoffzous L Lament with ihe Veffels of that name, and ter- 
 minates in the Pronatoi Qijadtaius. 
 
 Near the Hand, it tends a Branch dividing into others, which 
 fup !y the Mufcies and Integuments forming the Ball of the 
 Thumb. 
 
 The Trunk of the Nerve having given Branches to the Fore- 
 arm, patfes under the Annular Ligament of the Wrilf, where it 
 divides into Branches which are fituatea behind the Aponeuroiis 
 Paimaris, and Superficial Arch of the Arteries. 
 
 The principal Branches in the Palm come off in three divifions, 
 from which feven Nerves of confiderable lize are dilfributed to 
 the Thumb and Fingers. Of thefe, two go to the Thumb, and 
 one to the Radial fide of the Fore -finger ; ihe relt c. me off from 
 two-forked Trunks, ne3r the Heads of the Metacarpal Bones, 
 and l’u up I y the adjacent fides of the Fore and Middle, and of 
 the Middle and Ring-fin er. 
 
 Thefe Blanches lend Twigs through the Aponeuroiis to the 
 Integument, of the Palm, and others to the Mufculi Lumbri- 
 cales ; after which they accompany the Arteries fent out from the 
 Superficial Palmar Arch, bellowing Twigs to the adjacent parts 
 of the Fingers, at the points of which they terminate by nume- 
 rous Fibres. 
 
 The Ulnar Nerve, — which, like the former, is of great 
 fize, comes off chiefly from the laft: Cervical and Fil'd: Dorfal 
 Nerve. 
 
 It extends along the infide of the Triceps, frequently perfora- 
 ting fome of its Flelhy Fibres, and, near the Elbow, Hants a lit- 
 tle backwards, to get into a Groove between the inner Condyle 
 of the Os Humeri and Olecranon of the Ulna.' 
 
 From thence it pafles to the Fore-Arm, where, after perfora- 
 ting the Heads of the Flexor Muicles, it joins the Ulnar Artery 
 a little below its origin, and accompanies that veffel, — running 
 behind it all the way to the Hand'. 
 
 Under the Axilla, it fometimes receives a Branch from the 
 Spiral Nerve; and from this connexion, or from the Trunk of 
 the Ulnar Nerve itfeif, a Subcutaneous Branch is fent off, which 
 runs between the Triceps and Integuments, furnifhing Branches 
 to the latter for a confiderable way along the Fore-arm. 
 
 Near the under end of the Os Humeri, a Twig or two com- 
 monly go to the inner edge of the Triceps. 
 
 Under the bending of the Elbow, a Branch is given out to be 
 diftributed upon the Belly of the Flexor Ulnaris. 
 
 Immediately below the former, another Branch is produced, 
 which is difperfed upon the Flexor Profundus Digitorum. 
 
 About the middle of the Fore-arm, a Filament is tranfmitted 
 which adheres to the Ulnar Artery, turniflting fmall Twigs to 
 
-252 
 
 the Coats and Sheath of the Artery, and terminating in the 
 correfponding p rts of the Wi ift, and Integuments of the Palm. 
 
 Near the end of the Ulna, a confiderable Branch, termed Dor- 
 fa/is, is lent out, which turning between the Flexor Uinaris and 
 Urna, is directed to the back part of ihe Hand. 
 
 The Dorfal Nerve fends Branches to the Integuments of the 
 Weft and Metacarpus, which have various anaftumofes with 
 otheis ot the Spiral Nerve. 
 
 It lend- off a Branch which proceeds along the Ulnar fide of 
 the Little Finger; — and at the Heads of the Metacarpal Bones, 
 another fplitting into two Branches which run along the adjacent 
 lides of the Auricular. and Ring-fingers. 
 
 The Trunk of the Nerve paffes with the correfpond ; ng Artery 
 over the Annular Ligament into the Palm, where, like the Ra- 
 dial Nerve, it is covered with the Aponeurofis Palmai is. 
 
 In the Palm, it divides into Superficial and Deep Branches ; 
 the former deftined chiefly for the Fingers, the latter for the deep 
 region of the Hand. 
 
 The Superficial Palmar Nerves fiends— 
 
 Branches to the Ihort Mul'cles of the Little Finger : 
 
 A Branch to the Volar-ulnar fide of the Little Finger : and — 
 
 Another, which is loon fiplit into two fmaller Branches ; one to 
 the Radial fide of the Little Finger, the other to the Ulnar iide 
 of the Ring-finger. 
 
 The Deep Palmar Nerve links in between the Abdudlor and 
 Flexor Parvus Digiti Minimi, or perforates the head of the latter, 
 and forms an Arch which accompanies the Deep Arch of the 
 Arterie , under the tendon of ihe Flexors, and the Lumbricales 
 Mufcles. 
 
 The Deep Nerve gives — 
 
 A Branch to the Abdudlor Minimi Digity, and one to each of 
 the Interoffei : 
 
 A Twig to each of the Lumbricales, which enters from -be- 
 hind. : 
 
 Branches to the Flexor Brevis and Addtiftor PollicL. 
 
 The Nerve terminates at length by feveral fhort Branches 
 upon the Abdudlor Indicis Mufcle. 
 
 The Nerves on the Palm and correfiponding parts of the Fin- 
 gers, like the Arteries, are much larger than thole of the oppo- 
 lite fide of the Hand. 
 
 The Digital Nerves fiends off many lateral Branches to the In- 
 teguments and other parts of the Fingers, and terminate, each, 
 by a Brufh of Fibres, at the Apices of the Fingers. 
 
 Between the Branches of the Radial and Ulnar Nerve, differ- 
 ent Anaftomofes are frequently found ; and the fame may be ob- 
 ferved.between the Nerves of the Paimar and Dorfal fide of the 
 Fingers. 
 
25S 
 
 Intzucosto-Humerales. — Befides the Nerves of the Supe- 
 rior Extremity fent fron the Brachial Plexus, there are others be- 
 longing to it, which take their origin from the Tntercolfal Nerves, 
 and which may therefore be termed Intercojio-Humerales . 
 
 The Intercofio-Humeral Ner-ves, — confiftof a Branch from the 
 Second, and of another from the Third Intercoftal Nerves, both, 
 of which pafs out at the fore and lateral parts of the Thorax, 
 the one under the Second, and the other under the Third Rib. 
 
 The firft Nerve is joined by a fmall Branch with the Cutaneous 
 Nerve, or with the Cutaneous biternus of Wrisberg, and is af- 
 terwards difperfed by numerous Filaments upon the Axillary 
 Glands, and upon the Integuments of the Axilla and of the in- 
 ner part of the Arm. 
 
 The Second Nerve is conne&ed by one or more Branches with 
 the Firft, and fends lome Twigs to the Axillary Glands ; but is 
 chiefly diftributed upon the Integuments of the back-part of the 
 Ann, which it fupplies with many Branches, fbme of them ex- 
 tending as far as the Elbow. 
 
 ■oooooooo ©oooooooo 
 
 NERVES 
 
 WITHIN 
 
 THE THORAX . 
 
 THE Nerves, in each fide of the Thorax, confift of the 
 Phrenic, the Pars Paga of the Eighth Pair, the Great Sympa- 
 thetic, and the Intercojials ; all of which are covered and conceal- 
 ed by the Pleura, till they are expofed by difleftion. 
 
 The Phrenic or Diaphragmatic Nerve, has a fmall 
 Filament from the Second Cervical ; but is chiefly formed by a 
 Branch from the Third, and by one, and fometimes by two, 
 from the Fourth Cervical Nerve. 
 
 It defcends in the Neck, along the outer and fore-part of the 
 Scalenus Anticus Mufcle, and enters the Thorax behind the an- 
 terior extremity of the Firft Rib, between the Subclavian Artery 
 and correfponding Vein. 
 
 VOL. II. 
 
 Y 
 
254 
 
 In the Thorax it runs clown over the root of the Lungs, at d 
 then paffes along the Pericardium, to which it adheres clofely in 
 its way to the Diaphragm. 
 
 The Right Phrenic has nearly a ftraight direction oppofite to 
 the Superior Cava and Right Auricle ; while the left makes a 
 con fid (rafale Curve near its under end, correfponding with that 
 part of the Pericard um which covers the point of the Heart. 
 
 Upon the Surface of the Diaphragm, the Trunk is divided in- 
 to ieveral Branches, which are diftributed in a radiated form upon 
 the Flefhy Tides of that Mulcle. 
 
 Pahs Vaga. — The Pars Vaga, upon approaching the Thorax, 
 fends a Filament, and fumetimes two, termed Cardiac Nerves, 
 which join the Cardiac Branch of the Great Sympathetic, as al- 
 ready obfened. 
 
 It enters the Thorax between the Subclavian Vein and Artery, 
 and after giving off the Recurrent Nerve, paffes behind the root 
 of the Lungs. 
 
 Recurrent Nerve. — The Recurrent, — is reflected up- 
 wards, behind the Subclavian Artery in the right, and behind 
 the Arch of the Aorta in the left fide of the Thorax ; in confe- 
 quenceof which, the left nerve is the longer of the two. It af- 
 terwards afcettds in the Neck, adhering to the pollerior and late- 
 ral part of the Trachea, in its way to the Larynx. 
 
 It is connefted, near its origin, by one or two Branches of con- 
 fiderable fize, with the adjacent Ganglia of the Great Sympathe- 
 tic Nerve, and from the oppolitefide of its root, fends other con- 
 jiderable Branches to join thofe of the Eighth Pair, in the for- 
 mation of the Anterior Pulmonary Plexus of Nerves. 
 
 Near the Subclavian Artery, it is connected by different Fila- 
 ments to the Superficial and deep Cardiac Branches of the Sym- 
 pathetic Nerve. 
 
 In its afeent in the Neck, it tranfmits Pencils of Filaments, 
 which penetrate the Trachea, and are dilperfed upon its Internal 
 Membrane. 
 
 Behind the Thyroid Gland, it fends off minute Fibres to the 
 beginning of the-Efophagus and bottom of the Pharynx and 
 final 1 Twigs to the Gland itfelf. 
 
 Upon the inner fide of the Thyroid Cartilage, it furniflies a 
 Branch which continues a remarkable Anaftomofis with another 
 from the Internal Laryngeal Nerve. 
 
 At the back part of the Larynx, it is divided into many Fi- 
 briliat, which are diftributed to the different Mufcles fixed to the 
 Arytenoid Cartilage of the correfponding fide. 
 
 It has alfo fome connexions, fmaller than the one already 
 mentioned, with Branches of the Internal Laryngeal Nerve, and 
 fends minute Fibril Ice to the Internal Membrane of the Larynx ; 
 from which circumftauce the Recurrent Nerves are confidered as 
 the principal Inftruments of the Organ of Voice. 
 
29 , '> 
 
 The Pars Vaga, having transmitted the recurrent Nerve, gives 
 off Filaments which form connections with Brandies anting from 
 tiie urt ot ihc Recurrent of the fame and of the opposite fide. 
 
 They anatfomofe alfo by imall Finn !i ■- with the Cardiac 
 Branch of the Sympathetic, and then pafs to the fore-part of the 
 Bronchi, where they conilitu.e what is termed the Anterior Pul- 
 monary Plexus of Nerves. 
 
 The /interior Pulmona y Plexus, thus formed by Branches from 
 the Ei . hth Pair, wi h the aflillance of other's from the Recurrent 
 and Sy : pathetic Nerves, — exten ts acrofs t .e Great Branches -of 
 the Pulmonary Artery, and after tranl'mitting imall Filaments to 
 the Pericardium and to the Great Cardiac Nerve, furni flies many 
 minute Fibril.se, which accompany the R-atni ideations' of the 
 Bronchi and Pulmonary Blood-veffeis in the l'ubfcunce of the 
 Lungs. 
 
 From the Pars Vaga, a little below the origin of the Recurrent, 
 and likewife from the root of the Recurrent itfelf, Nerves are feut 
 ofF, which form a Plexus, to be difperfed partly upon the Flefhy- 
 glandular Suhifance of the Trachea, and partly embracing the 
 OEfophagus, and forming upon it the fniall OEfophageal 
 Plexus. 
 
 Behind the root of the Lungs, about fix or feven Nerves of 
 different fizes are fent off in a tranfverfe direction, which are 
 termed Pojier'tor.. Pulmonary Plexus, although they have few con- 
 nexions with each other. 
 
 The Pofterior Pulmonary Nerves, like the Anterior, follow 
 the Branches of the Bronchi and Blood-velfels in the fob ft a nee of 
 the Lungs, and, becoming gradually fmailer, fend erf minute 
 Twigs, which penetrate the A'r-Veffels, and are ultimately dif- 
 perfed upon their Internal Membrane. 
 
 After riving out the Pulm unary Nerves, the Pars Vagaisfplit 
 into Cords termed Great OEfophageal Plexus, which l'urrounds 
 the OEfophagus, lends Filaments into its Subdance, and is 
 joined by Funiculi of the Pais Vaga of the opposite tide. — It goes 
 afterwards through the Diaphragm, to be distributed upon the 
 Vifcera of the Abdomen. 
 
 From the Ganglia of the Great Sympathetic Nerve, at the 
 bo tom of the Neck and top of the Thorax, the principal Cardiac 
 Nerves are produced, which are difperled upon the Heart ; while 
 the continuation of the Trunk of the Sympathetic defeends in the 
 Thorax at the fide of the Vertebrae. 
 
 The Cardiac Nerves of the Right Side conftft of the 
 Cardiacus Magnus Profundus, and Cardiacus Minor, the latter of 
 which is termed by Scarpa Cardiacus Aortee > uperficialis . 
 
 The Cardiacus Magnus Profundus, — is principally 
 formed by Branches from the Second Cervical Ganglion of the 
 Sympathetic, and afterwards receives one or two Filaments from 
 
256 
 
 the Cardiacus Supremus, together with the Superficial Cardiac 
 and other Branches of the Eighth Pair, as formerly defcribed. 
 
 The Trunk, arifing in this manner from different fources, 
 partes between the Superior Cava and afcending Aorta to the Pof- 
 teiior Surface of the latter, and joins the Cardiac Branches of 
 theLeft Side. 
 
 By the addition of the Left Cardiac Nerves, a Plexus is formed, 
 termed Plexus Cardiacus Magnus of Haller, from which is 
 lent out a long Ganglion of a loft confidence, defcribed by 
 W risberg under the name of Ganglion Cardiacum. 
 
 From The Cardiac Ganglion, the following Branches are gi- 
 ven off, viz. 
 
 A Branch which, after tranfmitting Filaments to the Anterior 
 Pulmonary Plexus of the Eighth Pair, partes behind the Right 
 Divifion of the Pulmonary Artery to the Left Coronary Plexus 
 of the Pleat t .- 
 
 One or two Filaments, which unite with others fent from the 
 Anterior Pulmonary Plexus of the Eighth Pair, and go before 
 the Right Brandi of the Pulmonary Artery to the Bafe of the 
 Heart : 
 
 Branches of confiderable fize, parting partly over the right fide 
 of the Aorta, and partly between it and the Pulmonary Artery 
 to the Anterior Coronary Plexus : 
 
 Small Branches which unite with others coming from the 
 Trunk of the Great Cardiac Nerve, and pafs over the Aorta to 
 the Anterior Coronary Plexus. 
 
 The Nervus Cardiacus Minor arifes from the undermoft 
 Cervical Ganglion, creeps over the Arteria Innominata and Aor- 
 ta, and terminates in a Plexus formed by the Cardiac Nerves on 
 the left fide of the Aorta Afcendens. 
 
 The Left Cardiac Nerves are, the Cardiacus Superfci- 
 alis, and the Cardiacus Magnus Profundus. 
 
 The Cardiacus Superfici alis arifes from the upper part 
 of the Sympathetic Nerve, as formerly noticed, and partes be- 
 hind the Arch of the Aorta to the Plexus Cardiacus Magnus. 
 
 The Cardiacus Magnus Profundus Sinister, the up 
 per portion f which is fntaller than that of the right fide, arifes 
 by numerous roots from the middle, and from the lowed Gan- 
 glion of the Sympathetic Nerve. 
 
 It partes aero fs the Arch of the Aorta, and, after receiving the 
 Cardiac Branch of the Eigluh Pair, joins the Great Cardiac of the 
 right fide, t . artful in forming the Cardiac Plexus. 
 
 From the Cardiac Plexus, a Reticulum of Nerves extends up- 
 on the left fide of the afcending Aorta, which receives the Car- 
 diacs Minor, and a Filament or two from the Caidiacus Mag- 
 nus of the right fide, parting over the Aorta. 
 
 From this Reticulum, the Anterior or Right Coronary Plexus 
 is produced, which partes between the Pulmonary Artery and 
 
 
257 
 
 Aorta, and afterwards follows the courfe of the Trunk and 
 Branches of the Right Coronary Artery, along with which it is 
 difperfed upon the correfponding fide of the Heart. 
 
 The Great Cardiac Plexus, after fending a Filament or two 
 to the Lungs, gives off Nerves which unite, and form the Trunk 
 of the Great Deep Cardiac Nerve of the left fide, which has a foft 
 Gangliform appearance, and paffes along the correfponding iide 
 of the Pulmonary Artery. 
 
 Upon the Surface of this Artery, the Trunk foon divides in- 
 to Branches, which, after fending Filaments acrofs it to the right 
 Coronary Plexus, give origin to the Coronary Plexus of the left 
 fide, which attends the Trunk and Branches of the Left Corona- 
 ry Artery. 
 
 In the Left or Pofterior Coronary Plexus, the Nerves are lar- 
 ger than in the Right, correfponding with the Parts they have 
 tofupply; and, in both, they have repeated connexions with 
 each other on the furface of the Heart. 
 
 In general, the Nerves run cloie to the Arteries ; fome of them 
 being continued as far as the Apex, while others penetrate the 
 fubftance of the Heart. 
 
 The Great Sympathetic, having fent Nerves to the Heart, con- 
 lifts of an anterior and pofterior part, — the former going over, and 
 the latter under the Subclavian Artery. 
 
 Behind this Artery, the two parts unite into a Trunk, which 
 defcends in the Thorax over the Heads of the Ribs. 
 
 At the Head of each Rib, it fonns a fmall Ganglion of an ir- 
 regular lhape, which unites behind with each of the Intercoftal 
 Nerves, generally by two, and fornetimes by three fliort Bran- 
 ches. 
 
 From feveral of the Dorfal Ganglia of this Nerve, Filaments 
 are detached obliquely over the Vertebras to the Coats of the 
 Aorta. 
 
 From the Sixth, Seventh, and Eighth Dorfal Ganglia,-— and 
 frequently from a Ganglion above or below thefe, — Branches a- 
 life, which defcend obliquely upon the lides of the Vertebrae, 
 and unite into a Trunk, termed Ner-vus Splanchnicus ,— which 
 perforates the Appendix of the Diaphragm, and goes to the Vif- 
 cera of the Abdomen, from which circumftance the Nerve obtains 
 its name. 
 
 Belides the Nervus Splanchnicus, another, termed Splanchni- 
 cus Secundarius, or Accejj'orius, is generaliy obferved, which a- 
 rifes from one or two of the Dorfal Ganglia, below the origins 
 of the Splanchnicus, — near its termination,— -or runs feparate 
 from it into the Abdomen. 
 
 The Intercostal, or Costal, or Dorsal Nerves,— 
 after eicaping from th Vertebrae,— run in the Furrows at the 
 lower edges of the Ribs, in company with the Intercoftal Blood- 
 
 Vol. II. Y 2 
 
vefTeis, and proceed to the anterior part of the Thorax, between 
 the two Layeis of Intercoftal Mufcles. 
 
 Immediately after getting out from between the Vertebrae, 
 each is connected, as already noticed, by fhort Branches to the 
 Sympathetic Nerve. 
 
 Oppoiite to this conne&ion, they give principal Branches, 
 backwards, to the Mufcles lying near the Spine, and ferving for 
 the ereftion of the Trunk of the Body. 
 
 Through the reft of their courfe, they give Branches to the In- 
 tercoftal Mufcles, to the Mufcles and Integuments of the Tho- 
 rax, and alfo to tliofe of the Abdomen, and becoming gradually 
 Smaller, they at 1 all vanifh in the fore-part ©f the Body. 
 
 The Six upper Intercoftals fends Branches to the numerous 
 Mufcles, and to the Integuments covering the back-part of the 
 Thorax, to the Serratus Magnus, and to the upper part of the 
 Abdominal Mulcles ; while the remains of them, parting out 
 between the Ribs at the edge of the Sternum, are reflected along 
 with Branches of the Internal Mammary Blood-vefiels, to be dif- 
 perfed by fmall Filaments upon the Mamma, and likewife upon 
 the Mufcles and Integuments next the edge of the Sternum. 
 
 The Trunk of the Fil'd Intercoftal enters the compofition of 
 the Axillary Plexus ; — a Branch of it, however, runs along the 
 edge of the firft Rib, in the manner the other Intercoftals run a- 
 long their refpe&ive Ribs. 
 
 Two principal Branches,— one from the Second, and the other 
 from the Third Intercoftal,— are occupied in forming the Inter- 
 cofto-humeral Nerves, already defcribed 5 while a confklerable 
 Branch from the Fourth is reflected over the edge of the Latiffi- 
 mus Dorfi to the Integuments of the back-part of the Thorax. 
 
 The Six lower Intercoftals, after fupplying the adjacent Muf- 
 cles and Integuments of the Thorax, continue their courfe ob- 
 liquely forwards, and are difperfed upon the different Mufcles 
 and Integuments of the Abdomen ; — the Twelfth, running from 
 the laft Rib along the under end of the Abdomen, fends Fila- 
 ments which extend as far as the Skin of the Pelvis and Thigh. 
 
 NERVES 
 
 OF THE 
 
 CHYLOPOIETIC AND ASSISTANT CHYLOPOIETIC 
 VISCERA. 
 
 THE Nerves of the Chylopoietic and Afliftant Chylopoietic 
 Vifcera, are formed bv Branches, of the Par Vagum, and the Ra- 
 mi Splanchnki ot the Great Sympathetic Pair. 
 
259 
 
 The Pars Vaga of the Left Side , — defcending from the Great 
 OEfophageal Plexus of the E'ghth Pair, creeps along the fore- 
 part of the Cardia, detaches Filaments to the Left Hepatic Plex- 
 us, and divides into many Branches which are diftributed to the 
 upper and left portion of the Stomach. 
 
 The Right Pars Vaga paffes upon the pofterior part of the 
 Cardia, and fplits into two Fafciculi, one of which goes to the 
 root of the Hepatic Plexus and to the Coeliac Ganglion, while 
 the other, which is the principal one, is difperfed by numerous 
 Branches upon the under and left portion of the Stomach. 
 
 The Nerves of the two Falciculi have feveral connexions with 
 each other, about the Cardia and along the fmall Curvature of 
 the Stomach, and form a Plexus, by fome Authors termed Coro- 
 nary, from which Branches extend along the fmall Curvature as 
 far as the Pylorus. 
 
 The Ramus Splanchnicus and Splanchnicus Secun- 
 DARIUS have their origins from the Sympatbetics, and perforate 
 the upper and lateral part of the inferior Mufcle of the Diaphragm, 
 — as already mentioned in the Defcription of the Nerves of the 
 Thorax. 
 
 After entering the Abdomen, they expand their Fibres, and 
 unite with the lateral part of the Great Semilunar Ganglion. 
 
 The Semilunar Ganglion, — is formed by the Rami 
 Splanchnici of the Right and Left Sympathetics, with the addi- 
 tion of the Branches from the Eighth Pair. 
 
 It is of a long curved fhape, with the convex edge nndermoff, 
 and is compofed of many fmaller Ganglia, termed Coeliac, which 
 are of different fize and of irregular forms. 
 
 The Coeliac Ganglia are placed over the Aorta, about 
 the roots of the Coeliac and Superior Mefenteric Arteries, and 
 extend fome way upon the Flefhy Pillars of the Diaphragm. 
 
 From the Coeliac Ganglia innumerable Nerves blue on all lides 
 forming a Plexus, termed by fome Authors Solar, which extends 
 along the Trunks and Branches of the Coeliac and Superior Me- 
 fenteric Arteries. 
 
 The Nerves upon thefe Arteries are fo intermixed with each o- 
 ther and with Cellular Subftance, as to form confufed Webs ; 
 the name of Plexus, however, is (fill retained, and the particu- 
 lar name of each Plexus is derived from the Artery which it fur- 
 rounds, or the Vifcus to winch it belongs. 
 
 The Hepatic Plexus, — after giving Twigs to the Renal 
 Glands, fends Filaments to the Diaphragm, which accompany 
 the Diaphiagnmic Arteries, and anafto.nofe with Branches of 
 the Phrenic Nerves. 
 
 It afterwards du :des into Ri^ht and L Plexufes, correfpond- 
 ing with the Pigln and Left B 'niches of the Hepatic Aitety, or 
 with the Right and Left Trunks, when fuen are prefent. 
 
260 
 
 The Left Hepatic Plexus furniflies feveral Branches to the Sto- 
 mach, which intermix with thofe of the Eighth Pair, upon the 
 fmall Curvature. 
 
 Th? Right Hepatic Plexus imparts Branches to the correfpond- 
 ing part of the Pancreas, to the fmall end of the Stomach and 
 beginn ng of the Duodenum, and gives origin to the Right Gaf- 
 tro- . p-ploic Plexus, which attends the Artery of the fame name, 
 diftnbuting its Filaments to the great Curvature of the Stomach, 
 and to tlu Omentum Majus. 
 
 The Hepatic Plexufcs lurround the Hepatic Artery and Vena 
 Portae, and, after fending feveral Filaments to the Biliary Duffs 
 and Gall-Blarlder, follow the Branches of the Blood-veffels 
 through rhefubltance of the Liver. 
 
 The Splen'c Plexus, coinpofed of feveral fmall Filaments, 
 furrounds the Splenic Artery, gives T igsto the Pancreas, and 
 then accompanies the Veffels into the Spleen. 
 
 The Superior. Mesenteric Plexus, forms a Vagina, 
 which furrounds, and in a great pa t conceals the Trunk of the 
 correfponding Artery. 
 
 From this Plexus, numberlefs Filaments are produced, — many 
 of them extremely minute, — which run through the Melentery, 
 partly with the Blood-veffels, and puily atadillance from them; 
 and which, after fupplying the Coats of the Veffels and Mefen- 
 teric Glands, are diftributed to the fmall Intellines in genera), 
 and to the right portion of the Colon. 
 
 The Nerves of the Colon are, in proportion to the part they 
 have to ftipply, larger than thole of the Small Inteftines, and in 
 feveral places form Arches, wh.ch are fituated at the fides of the 
 Arteries. 
 
 The Coeliac Ganglia fend down, along the Aoria, a Vagina 
 fimilar to that lurrounding ihe Superior Mefenteric Artery, 
 which is joined by other Nerves from the Trunk of the Sympa- 
 thetic continued along the Lumbar Verteb: as. 
 
 From the Aortic Vagina or Plexus, a Ptocefs is fent off, term- 
 ed Inferior Mese tery Plexus, which furrounds the 
 Trunk of the Inferior Mefentei ic Artery, and follows it to the 
 left portion of the Colon, and to the Reftuin; — the Nervous Fi- 
 laments forming Arches in feveral places, as in the Superior Me- 
 fenteric Plexus. 
 
 The Aortic Plexus receiving frefh fupplics from the Trunks 
 of the Sympathetic^, fends down a Plexus, commonly termed 
 Hypogc.fi’ ic, which pafles ver the end of the Aorta, and, 
 upon the laft Lumbar Vertebra, fplits into right and left por- 
 tions, which defcend to the Vifcera contained in the Pelvis. 
 
261 
 
 NERVES 
 
 OF THE 
 
 ORGANS OF URINE AND GENERATION. 
 
 THE Nerves of the Organs of Urine and Generation conlift 
 of the Renal and Hypogajlric Plexus, and of the Spermatic and 
 Pudic Branches. 
 
 The Renal Plexus is compofed of Nerves fent from the 
 Coeliac Ganglia, joined by fome others derived from one or two 
 of the Ganglia, of the Sympathetic Nerve in the bottom of the 
 Thorax. 
 
 It is interfperfed, at its beginning, with fmall Ganglia, termed 
 Renal, and is afterwards divided into Anterior and Pofterior 
 Plexufes, which extend along the correlponding Surfaces of the 
 Renal Artery to the Subftance of the Kidney. 
 
 From the Renal Plexus, fmall nervous Twigs afcend to the 
 Renal Gland, which is turnilhed with others from the Coeliac 
 Ganglia and root of the Hepatic Plexus. 
 
 The Renal Plexus alfo fends down Filaments to fupply the’up- 
 per portion of the Ureter ; — the under receiving Nerves from 
 the Hypogaftric Plexus. 
 
 The Hypogastric Plexus, the origin and courfe of which 
 have been already mentioned, is connefled by different Nerves to 
 the adjacent Trunks of the Great Sympathetic and Sacral Nerves, 
 and fends many Filaments to the Reftuni, Bladder, and Sper- 
 matic Veffels in the Male ; and to the Reftum Bladder, Uterus, 
 and Vagina in the Female. — The Nerves of the Uterus are pro- 
 portionally fmall. They pafs into its fubftance at the Cervix, 
 and follow the courfe of the Blood-vefTels. 
 
 Spermatic Nerves. — The Spermatic Nerves are very mi- 
 nute — They confift of a Superior or Internal, anti of an Inferi- 
 or or External fet of Capillary Branches. 
 
 The former are derived from the Renal and Aortic Plexus, 
 and accompany the Spermatic Blood veffels in their courfe 
 through the Abdomen, and afterwards to the TefHcle. 
 
 The latter are fent off from a Branch of the Second Lumbar 
 Nerve, which running behind the Tendon of the External Ob- 
 lique Mulcle, near Poupart’s Ligasnent, detaches a Filament, 
 which f in the Male, goes to the Spermatic Cord, and more par- 
 ticularly to the Cremafter Mulcle; and in the Fem-.le, is reflec- 
 ted along the L'gamentum Rotundum to the Uterus. 
 
 Nervi Pudici. — The Nervi Pudici arife in two Fafciculi, — a 
 Superior and Inferior — which are formed by Fibrillae from all the 
 Cords entering the compoution of the Sciatic Nerve. 
 
262 
 
 The Superior Fafciculus is formed, more particularly, by 
 Threads fi -om the two under Lumbar and two uprer Sacral 
 Nerves the Inferior is compofed of a fmall Cord from the Se- 
 cond, and a large one from the Third Sacral. 
 
 The Fafcicub pafs through the under part of the Notch of the 
 Os Ilium, and afterwards between the Sacro feint ic Lit aments, 
 ami follow the Pudic Blood-vefitls, anallomofing in f 6 me places 
 with each other by Oblique Branch s. 
 
 They fend many Blanches to the Mufcles and other parts about 
 the Anus and Perineum, and then pafs forwards to fupply the 
 different parts of the Penis. 
 
 On the Penis, the Nerves follow the courfe of the Arteries, the 
 Superior Fafciculus conllituting the Nervus Dorfali , and the In- 
 feri or iving Blanches to the under part of tiie Penis. 
 
 The Nervus Dorfalis which is the mod conhderable of th.e 
 Penis, runs forwards between the correfpdnding Aitery and Vena 
 Magna, expanding into many Branches which after fupplying 
 the Corpus Cavernofum and Teguments of the correlponding 
 fide, terminate in the Subltanceof the Glands. 
 
 NERVES 
 
 OF THE 
 
 LOINS, PELVIS, AND INFERIOR EXTREMITY. 
 
 THE Nerves of the Loins, Pelv’sy and Inferior Extremity, 
 con lift of the continuation or inferior portion of the Sympathetic, 
 and of the Trunks and Branches of the Lumba and Sacral 
 Nerves. 
 
 The Sympathetic Nerve, after reaching the Abdomen, 
 makes a fweep forw ixls upon the anterior and lateral part of the 
 Lumbar Vertebrae, between the Tendinous Crura of the Dia- 
 phragm and the Pfoas Mufcle. 
 
 It afterwards defeends into the Pelvis, nearly of the fame fize 
 as in the fuperior paits of the Body, and pailes over the anterior 
 Surf.ce of the Os Sacrum, at the inner fide of the Great Sacral 
 Foramina. 
 
 Towards the lower part of the Pelvis, it becomes conftderably 
 fmaller, and at laft finifltes its courfe upon the furface of the Os 
 Coccygis, where it unites into an Arch with its fellow of the op- 
 pofite fide. 
 
In the Loins, it forms Ganglia fimilarto thofe in the Thorax, 
 each of which is conne&ed behind, by two or three long (lender 
 Branches, to the roots of the Lumbar Nerves, and before, by 
 other (lender Nerves to the Aortic Plexus. 
 
 In the Pelvis alfo, it forms Ganglia which are connected to the 
 Sacral Nerves on one fide, and to the Great Sympathetic on the 
 other, by crofs Branches. 
 
 Filaments are fent off in the Pelvis, from the Sympathetic to 
 the Mufcles and Membranes about the Os Coccygis, and to the 
 Inteftinum Reftum. 
 
 Lumbar. Nerves. 
 
 The Five Lumbar Nerves, immediately after emerging 
 from theBones, communicate with each other and with the Sym- 
 pathetic Nerve,- and lend large Blanches backwards to the Muf- 
 cles and Integuments on' the pofterior part of the Loins. 
 
 By the r connections with each other, they compofe a Piexus 
 termed Lumbar, which is iiruated behind the Pfoas Mufcie, and 
 fends Branches outwards to the Quadratus Lumborum, and to 
 the Flexors of the Thigh. 
 
 The First .Lumbar Nerve is connected by a final! Branch 
 to the Twelfth Dorfal, and by its Trunk to the Second Lum- 
 bar. 
 
 It gives Twigs to the Quadratus, and a principal Branch which 
 pafles over that Mulcle towards the Spine of the Os ll um, 
 where it fends Nerves to the Integuments of the Pelvis to the up- 
 per and outer pait of the Thigh, to the un.ier end of the Abdo- 
 minal Mufcles, and to the Integuments of the Pubes. 
 
 The Second Lumbar perforates the Pfoas, to which it gives 
 Branches} and afterwards runs into the Third. 
 
 From tne Second Lumbar, the Spermaticus.Jixternus is' fent 
 off, which perforates the under part of the Tranfverfe and Inter- 
 nal Oblique Muicies, near the anterior encTof the Spine, or Creft 
 of the Ilium. 
 
 It goes next under the Tendon of the External Oblique, at 
 the inner fide of Poup art’s Ligament, and palling through the 
 Abdominal Ring, is dilfributed to the Scrotum and to the Sper- 
 matic Cord in the Male. 
 
 In the FemaL, it lends a Branch to the Labia, and another, 
 reflected along the Ligamentum Rotundum, to the Uterus ; and 
 in both Sexes, it gives Branches alfo to the Integuments and 
 Glands of the Groin. 
 
 Another Branch, fmaller than the former, arifes alio from the 
 Second Lumbar, and palling between the Pfoas Mufcie and Ver- 
 tebrae, conftitutes the Cutanec u; Med'us of the Thigh. 
 
 The Cutaneous Medius defeends in the fore part of the Thi<di, 
 oppolite to the inner edge of the Rt&us Mufcie, and fupplies the 
 Integuments near it as far as the Knee, — one Branch of it anaf- 
 tomofmg with another of the Cutaneus Anterior. 
 
Branches of the Second, Third, and Fourth Lumbars, form 
 a Nerve of confiderabie fize, called Obturator , which palfes be- 
 tween the External and Internal Iliac Blood-vefl'els, and along the 
 fide of the Pelvis. 
 
 The Ob turator Nerve accompanies the Blood-velfels, of 
 the fame name, through the upper part of the Obturator Muf- 
 cles and Ligament, and having furnifhed Branches to the Ob- 
 tutator and Pedlineus Mtifcles, it divides into an Anterior and 
 Pofterior Fafculus ; the former difperfed upon the two fmall 
 Addudtors and Gracilis, the latter upon the Great Adduftor of 
 the Thigh. 
 
 The principal parts of the Trunks of the four upper Lumbar 
 Nerves, efpecially of the Third and Fourth, unite and form 
 a Nerve of great fize, termed Crural , or Anterior Crural. 
 
 The Crural Nerve, after bellowing Branches upon the 
 Iliacus Interims, pafl'es behind, then at the outtide of the Pfoas 
 Mufcie, to get to the Thigh. 
 
 In its courfe from the Abdomen, and at the upper part of the 
 Thigh, it is fituated at the outfide of the Femoral Artery, which 
 lies between it and the correl'ponding Vein. 
 
 Behind Poupart’s Ligament, it is divided into many Branch- 
 es, which are dilfributed to the Mufcles and Integuments on the 
 fore and lateral parts of the Thigh,— one Branch in particular de- 
 fending upon the Leg. 
 
 The Branches are as follow : 
 
 The Cutaneus Anterior, — more internal than the Cutaneous 
 Ivied i us, which erodes over the middle of the Sartorius Mufcie, 
 and after fupplying the adjacent Integuments, terminates in the 
 Skin and Cellular Subftance, at the fore and inner part of the 
 Knee. 
 
 The Cutaneus Internus , — (fill more internal than the former, 
 —which paffes between the Sartorius and Triceps, and, after 
 giving Filaments to the Integuments at the iniide of the Thigh, 
 terminates in thofe at i he under and fore part of the Knee. 
 
 The Deep Branches of the Crural Nerve, which are confide- 
 rably larger than the Superficial, go to the Pedlineus and Tri- 
 ceps, to the Sartorius and Gracilis, and to the four Extenfors 
 of the Leg, and furnifh Twigs to the Femoral Blood-velfels 
 alfo. 
 
 The Branch to the Leg, termed Saphenus, defends between 
 the Sartorius and Triceps, and afterwards behind the Tendon of 
 the former, to the inner fide of the Tibia. 
 
 Under the Knee, it gives off a Branch, named by Fischer, 
 Saphenus Minor, which goes down a little behind the Saphenus, 
 and, furnifhing Filaments to the Integuments of the inner and 
 back-part of the Leg, terminates behind the Malleolus Internus, 
 on the Integuments of the Foot. 
 
265 
 
 The Trunk of the Saphenus attends the Vena Saphena Major,, 
 fending many Nervous Threads obliquely forwards to the Inte- 
 guments on the inner and fore-part of the Leg, and is at length, 
 confumed upon the Skin and Cellular Subftance of the upper and 
 inner part of the Foot. 
 
 The remaining part of the Fourth Lumbar Nerve unites with 
 the Fifth into a Trunk which defcends into the Pelvis. 
 
 Sacral Nerves. 
 
 The Sacral Nerves confift of fmall Poferior, and large 
 Anterior Trunks. 
 
 The Posterior Sacral Nerves pafs out by the Holes in 
 the back-part of the Os Sacrum, and anaftumofe with each other, 
 and with fome of the Branches of the Gluteal Nerves. 
 
 They fend out a few tender Fibrillas, which are difperfed upon 
 the Mufcles covering the back-part of the Os Sacrum, and upon 
 the Glutei Mufcles and their Integuments. 
 
 Anterior Sacral Nerves. — Of the Anterior Sacrals,— 
 the two uppermoft are the larged:: The red: 1'uddenly dimimlh in 
 fize, the lad being the fmalleft of the Spinal Nerves. 
 
 They go through the Holes in the fore-part of the Os Sacrum, 
 and, foon after their exit, are united with each other, and with 
 Branches of the Sympathetic Nerve. 
 
 The First, Second, and Third Sacrals, join into a 
 Trunk, which receives the common one fent down from the Fourth 
 and Fifth Lumbars, and forms a Plexus which fends out the Scr- 
 atic, the larged: Nerve of the Body. 
 
 The roots of the Sciatic Nerve give origin to the Fafciculi 
 which compofe the Pudic Nerve, formerly defcribed, and alfo to 
 the Gluteal Nerves which are difperfed upon the Mufcles of the 
 Hips. 
 
 The Gluteal Nerves run in two Fafciculi,— a Superior, 
 arifing immediately from the Trunk formed by the two lad Lum- 
 bars, and — an Inferior, coming off from the two lad Lumbars 
 and fird Sacrals. 
 
 The Superior Fafciculus goes through the upper part of the 
 Notch of the Os Ilium, to be difperfed upon the two fmaller 
 Glutei Mufcles. 
 
 The Inferior Fafciculus paffes through the under part of the 
 fame Notch, and below the Pyriform Mufcle, to be didxibuted 
 upon the Gluteus Maximus and Integuments. 
 
 The Fourth Sacral fends Filaments to the Hypogadric 
 Plexus, others to the Mufcles and Ligaments of the Os Coccy- 
 gis ; the red pafs outwards to the Mufcles and Integuments about 
 the Anus. 
 
 The Fifth, which is fcarcely above the fize of a Filament, 
 after giving Twigs to the Coccygeus Mufcle, perforates the Sa- 
 
 Vol. II. Z 
 
266 
 
 •cro-fciatic Ligaments, and terminates in the Mufcles and Integu- 
 ments of the Anus. 
 
 Sciatic Nerve. — The Sciatic or Ifchiatic Nerve, — paffes ob- 
 liquely through the Notch of the Ilium, under the Pyriform Muf- 
 cle. It goes afterwards over the other (hort Rotator Mufcles, 
 and is placed between the Tuber Ifchii and Trochanter Major, 
 •where it is coveied by the Gluteus Maximus. 
 
 After leaving the Pelvis, it defcer.ds in the back-part of the 
 Thigh, firft between the Long Flexors and Addudlor Magnus, 
 and then between the latter and Os Femoris to the Ham, where 
 it obtains the name of Popliteus. 
 
 In this courfe, it gives out the following Branches, which fup- 
 p'ly the Mufcles and Integuments on the back-part of the Thigh, 
 viz. 
 
 T<ivigs to the Rotators of the Thigh, which come off from it 
 after its palfage through the Sciatic Notch. 
 
 The Cutaneous Pojlerior Superior, which arifes wifhin the Pel- 
 vis, and palling out with the Sciatic, is divided into Branches, 
 fome of which are refle&ed to the Scrotum in the Male, and to 
 the polterior parts of the Labia in the Female, and, in both, to 
 the Skin aboat the Anus and Peiineum. — The principal Branches 
 of this Nerve pafs downwards, fupplying the Integuments of the 
 back -part of the Thigh, as far as the bending of the Knee. 
 
 A Branch to the long Head of the Biceps. 
 
 Two fmall Nerves, the one termed Cutaneus Internus Superior , 
 which comes off near the upper part of the Thigh, and vanifhes 
 in the Skin, a little farther down ; the other termed Cutaneus In- 
 ternus Inferior, which arifes near the former, goes down the pof- 
 terior part of the Thigh, and then defeending upon the inner 
 Head of the Gallrocnemius Externus, terminates in the Integu- 
 ments of the Calf of the Leg. 
 
 A Large Common Trunk, and fometimes, inftead of it, fepa- 
 ratc Branches, which arife near the middle of the Thigh, and 
 are diilri buted to the Adduflor Magnus, Semimembranolus, Bi- 
 ceps, and Semitendinofus. 
 
 Nervus Popliteus. — The Popliteal Nerve is fituated be- 
 tween the Ham-ftrings, and between the Skin and Popliteal 
 Blood-veffels. 
 
 A little above the bending of the Knee, it is divided into a 
 Small External, and a Large Internal Branch ; the former named 
 Fibular, and the latter Tibial Nerve. 
 
 The Tibial and Fibular Nerves adhere, for fome way, by Cel- 
 lular Subftauce, and even the Trunk of the Sciatic may be fplit 
 into thefe two Nerves for a confiderable way up the Thigh. 
 
 The Fibular, — tefmed alfo Peroneal Nerve, — fends off, 
 at its beginning, the Cutaneus Externus, which is a fmall 
 Branch giving Twigs to the under end of the Biceps, and which, 
 
267 
 
 after running down on the Outer Head of the Gaftrocnemius, 
 difappears in the Integnmenis of the fame fide of the Leg. 
 
 Over the outer Condyle of the Os Femuris, it gives off another 
 Cutaneous Branch, winch goes over the Gaftrocnemius Mufcle, 
 and, after anaftomofing with a Branch of the Tibialis, goes along 
 the outer part of the Leg, and terminates in the Integuments of 
 fide of the foot. 
 
 The Fibular Nerve afterwards paffes over the Head of the Fi- 
 bula, and divides into Superficial and Deep Branches , which fup- 
 ply the Mufcles and Integuments of the outer and fore-part of 
 the Leg. 
 
 The Superficial Fibular croffes over the Fibula, immediately 
 under its articulation, and perfoiating the Peroneus Longus, and 
 going over the Brevis, it gives Branches to both, and after- 
 wards becomes Subcutaneous, about the middle of the outerparts 
 of the Leg. 
 
 It fends Branches to the Metatarfus, to the Extenfor Digitorum 
 Brevis, and others, which, after anaftomofing upon the upper 
 part of the Foot, fumilh Dorfal Branches to the larger Toes. 
 
 The Deep Fibular Nerve croffes over the Fibula immediately 
 above the former, and divides into feveral Branches, viz. 
 
 A Reflected Branch tG the foft parts of the joint t 
 
 A Branch to the Peroneus Longus r 
 
 A Branch to the Tibialis Anticus ; 
 
 Branches to the Extenfor Pollicis. and Extenfor Digitorum 
 Longus : 
 
 Filaments which creep along the Perioftcum of the Tibia, and 
 others which adhere to the Coats of the Tibia! Artery. 
 
 The longeft Branch of the Nerve accompanies the Anterior 
 Tibiai Artery, and divides upon the Foot into Branches, which- - " 
 have fome connexions with each other, and fupply the Exten- 
 for Digitorum Brevis.— Some Filaments continued from thefe 
 Branches run to the Mufculi Interoffei, while others of more 
 confiderable fize go to l’ome of the innermoft Toes, one Twig 
 finking with a Branch of the Anterior Tibiai Artery to the Deep 
 Mufcles of the Sole. 
 
 The Tibial Nerve paffes between the Heads of the Gaftroc- 
 nemius Mufcle, and, after perforating the origin ©f the Soleus, 
 defeends between it and the Flexor Digitorum Longus, upon he 
 Pofterior Tibiai Artery, to the under part of the Leg j in which 
 courfe it fends off the following Nerves, viz. 
 
 The Communicans Tibia, — -which accompanies the Vena Saphe- 
 na Minor in the back part of the Leg, and to the outer part of 
 the Foot- 
 
 Behind the Belly of the Gaftrocnemius, the Communicans 
 fends a Branch to be confumed in the Fat ; and a little lower, it 
 anaftomofes with the communicating Branch of the Fibular 
 Nerve. 
 
268 
 
 The under part of this Nerve is difperfed upon the Integuments 
 of the outer Ankle and adjacent fide of the Foot, fome Branches 
 pafling as far as the Dorfal fide of two or three of the fmaller 
 Toes. 
 
 Branches to both Heads of the Gaftrocnemius, to the Planta- 
 ris, and to the Soleus. 
 
 Near the middle of the Leg, it fends Branches to the Tibialis 
 Pofticus, to the Flexor Digitorum and Flexor Pollicis. 
 
 One or two Cutaneous Branches, difperfed upon the Skin at the 
 under and inner part of the Leg. 
 
 Near the Ankle a Branch which pafl'es behind the Tendo Achil- 
 lis, principally to the Integuments of the outer and back-part of 
 the Foot. 
 
 Tlie Tibial Nerve pafl'es afterwards between the Arteries and 
 Os Calcis into the Sole. 
 
 In the hollow of the Os Calcis, after detaching Branches to 
 the parrs adjacent, it divides into Internal and External Plantar 
 Nerves, which are nearly of equal fize. 
 
 . The Internal Plantar Nerve runs near the inner fide of 
 the Sole, fends Filaments to the Abduftor Pollicis, Flexor Digi- 
 torum Brevis, and Flexor Digitorum Acceflorius, and Twigs to 
 the Lumbricales. 
 
 It afterwards gives out four large Branches fplitting into others, 
 which run with the Arteries along the Plantar fides of the three 
 firft Toes, and inner fide of the fourth Toe, — in the manner the 
 Radial Nerve runs along the correfponding Fingers. 
 
 The External Plantar Nerve, fends branches to the 
 Heel, and pafl'es with the Artery of the fame name to near the 
 outer edge of the Sole, where it fpl its into three principal Bran- 
 ches. 
 
 The two firft run to the adjacent fides of the fourth and fifth 
 Toes, and outer fide of the Little Toe, the inner one often an- 
 aflomofing with a correfponding Branch of the Internal Plantar. 
 
 The thiid forms an Arch correfponding with that of the Ex- 
 ternal Plantar Artery, furnifhes Bran- hes to the fliort Mufcles 
 of the Little Toe, to the Interoflei, Lumbricales, and Tranfver- 
 falis, and terminates in the fhort Mufcles of the Great Toe. 
 
 The Plantar Digital Nerves fend Filaments to the Integu- 
 ments, and upon the Toes anaftomofe with each other, and with 
 the Dorfal-digital Nerves, — as the Palmar Digital Nerves do in 
 the Hand. 
 
 FINIS. 
 
INDEX TO FYFE’S ANATOMY. 
 
 VOLUME SECOND. 
 
 A 
 
 Page. 
 
 Page. 
 
 Abdomen, Of the 
 
 9 1 
 
 Appendices vermiformes of the 
 
 
 
 
 cerebellum 
 
 20 
 
 phatics of the under part 
 
 
 Appendix vermiformis of the 
 
 
 of the, 
 
 OO 
 
 tr 
 
 caecum 
 
 98 
 
 
 
 Aqua labyrinthi, 
 
 55 
 
 the containing parts of the 
 
 21 1 
 
 AquaduElus Fall opii ) 
 
 S3 
 
 Abducentes, or iixth pair of 
 
 
 
 18 
 
 nerves. 
 
 232 
 
 Aqueous humour 
 
 3 a 
 
 Absorbent System, of the 
 
 153 
 
 Arachnoidea tunica, 
 
 12 
 
 Acceffory nerves to the eighth 
 
 
 Arbor vitas. 
 
 20 
 
 pair, 
 
 240 
 
 Arch of the aorta, 
 
 174 
 
 Accrvulus cerebri. 
 
 !9 
 
 Arches of the palate 
 
 62 
 
 Acufticus nervus, 
 
 
 Arcus plantaris arteriofus, 
 
 221 
 
 Addufbor oculi, 
 
 37 
 
 -■ volaris piofunaus, 
 
 1 Q4 
 
 Adeps, 
 
 8 
 
 ■ ■ fuperiicialis. 
 
 i ? S 
 
 Adipofe arteries and veins, 
 
 207 
 
 Arteries, of the. 
 
 1 69 
 
 Alas vefpertilionis, 
 
 *34 
 
 Articular nerve of the ihoulder 248 
 
 Albuginea tunica. 
 
 124 
 
 Arytenoid cartilages, 
 
 
 Almonds of the Ears, 
 
 63 
 
 Auditorius nervus, 
 
 233 
 
 Alveolar arteries, 
 
 179 
 
 Auricles of the heart, 
 
 76 
 
 Amnios, 
 
 146 
 
 Auris tranfverfus. 
 
 45 
 
 Amygdalae, 
 
 63 
 
 internes. 
 
 5° 
 
 Anthelix, 
 
 44 
 
 Axillary artery, 
 
 iqt 
 
 Antitragicus, ? 
 
 
 
 16 6 
 
 Antitragus, 3 
 
 45 
 
 plexus, 
 
 247 
 
 Aorta, general ccurfe of the 
 
 174 
 
 Azygos vena, 
 
 199 
 
 Appendages of the ikin 
 
 6 
 
 
 
 Ball of the Eye, 
 
 B 
 
 26 
 
 Bladder of urine, blood-vefi'ds 
 
 
 , coats of the. 
 
 ib . 
 
 of the. 
 
 208 
 
 
 
 
 
 - 
 
 
 
 — , mufcles of the. 
 
 36 
 
 of the, 
 
 158 
 
 veffels of the, 
 
 33 
 
 Blood-Vessels in general, 
 
 
 181. 
 
 186 
 
 of the, 
 
 169 
 
 • ■ , nerves of the 
 
 38 
 
 Brachial artery, 
 
 192 
 
 
 228 
 
 — plexus of nerves, 
 
 247 
 
 Bafilar Art ry. 
 
 184 
 
 Brain, of the. 
 
 9 
 
 Baiilic vein, 
 
 196 
 
 , arteries of the. 
 
 182 
 
 Bladder of urine, 
 
 120 
 
 ; veins of the, 
 
 m 
 
 VOL. II. Z 2 
 
INDEX. 
 
 page. 
 
 Brain, nerves which arife 
 
 from the, - . 22 y 
 
 Bronchi, - s. gg 
 
 Ccecum inteftinum, - ^ 
 
 — abibrbents of the 160 
 
 Calamus fcrjptorius, _ 2 o 
 
 Canals of the cochlea, - rj 
 
 Capfuls renales, - II5 
 
 ~ , blood-veifels 
 
 of the - . 1 1 7.207 
 
 ■, lymphatics 
 
 163 
 94 
 2 55 
 176 
 ib. 
 
 180 
 26 
 
 244 
 174 
 22-2 
 I 99 
 IOI 
 
 7 
 
 181 
 186 
 
 !5 
 
 fage. 
 
 Bronchial arteries and veins, 88. 198 
 Buccales arteris, _ -179 
 
 Bulb of the urethra, - ijg 
 
 of the 
 Cardia, 
 
 Cardiac Nerves, 
 
 Carotid arteries, 
 
 * artel 7 > external, 
 
 ■ — , Internal, 
 
 Caruncula lacrymalis, 
 Cauda Equina, 
 
 Cava, general courfe of the, 
 — ■ , fuperior, 
 
 , inferior, 
 
 Cavvl, 
 
 Cellular fubftance,. 
 
 Centralis retins arteria, - 
 
 * ■ vena, 
 
 Centrum ovale of Vieujfens, 
 
 femicirculare gerainum 16 
 
 Cephalic vein. 
 
 Cerebellum, 
 
 , arteries of the. 
 
 Cerebral arteries, 
 
 Cerebrum 
 Cervical nerves, 
 
 Cervical arteries, 
 
 Cheek, 
 
 Chorda tympani, - 5 
 
 Chorion, 
 
 Choroid coat, 
 
 " ■ plexus, 
 
 Chvlopoietic and Assist 
 Ck y 1. opoietic Viscera, 
 of the, 
 
 196 
 
 19 
 
 184 
 
 182 
 
 J 3 
 
 246 
 
 190 
 
 Cilia, 
 
 Ciliary arteries, 
 ■ veins. 
 
 afcf jvbents of the, 
 nei res of the, 
 
 29 
 
 24 
 
 20 
 
 Ciliary circle, 
 
 — glands, 
 
 procefl'es, w 
 
 Cinerltious fubftance of the brain 14 
 Circulus iridis arteriofus, 182 
 Circumflexa fe- f interna, ? 
 
 moris arteria, \ extetna, $ 2I + 
 
 hu- J anterior, 7 
 
 meris arteria, £ pofterior, j 
 -offis ilii arteria. 
 
 Circumvolutions of the brain, 
 — —of the cerebel- 
 
 192 
 
 212 
 
 13 
 
 Circus arteriofus o( Willis, 
 Clitoris, 
 
 Coats of the eye, 
 
 Cochlea, 
 
 Cteliac artery, 
 
 Colic arteries, 
 
 ■ veins. 
 
 Colon, 
 
 — — , abforbents of the, 
 Columns valvuls VieuJJhrii, 
 
 carnes of the heart, 
 
 Commiffurs eerebri, 
 Commiflura mollis of the optic 
 thalami, 
 
 Communicans faciei, nervus. 
 Cord, umbilical, 
 
 Cornea, 
 
 Cornua ammonis, 
 
 Cornua of the ventricles of the 
 
 20 
 
 185 
 
 138 
 
 26 
 Si 
 
 200 
 
 203 
 
 204 
 
 9 8 
 
 160 
 
 20 
 
 77 
 
 18 
 
 16 
 
 2 33 
 
 144 
 
 27 
 
 17 
 
 57 
 
 btain, 
 
 15 
 
 r 2 35 
 
 Cor. .nary veffels of the heart, 
 
 82 
 
 146 
 
 artery of the lias. 
 
 177 
 
 29 
 
 — ■ ■■ of the ftomach 
 
 2 00 
 
 16 
 
 Corpora albicantia, 
 
 21 
 
 ANT 
 
 — cavernofa penis, 
 
 128 
 
 
 ■ fimbriata, or T tenia 
 
 
 91 
 
 Hippocampi, 
 
 17 
 
 200 
 
 Corp ra olivaria, 
 
 22 
 
 rs 8 
 
 — ■ pyramidalia, 
 
 ib. 
 
 2 5 8 
 
 Col pus adipolum, 
 
 8 
 
 2 5 
 
 cailofum. 
 
 !3 
 
 181 
 
 —■ ciliare. 
 
 3° 
 
 187 
 
 ■ " 1 - mucofum, 
 
 4 
 
INDEX, 
 
 page. 
 
 page. 
 
 Corpus fpongiofum urethrae, 129 
 
 Cortical fubftance of the brain, 14. 
 Coftal nerves, - 257 
 
 Cranium, nerves which pafs 
 
 through the bafe of the, 227 
 
 Cricoid cartilage, - 65 
 
 „ f cerebri, 7 
 
 Cl ' ura \ cere belli, 3 ' 21 
 
 Cryftalline len9, 32 
 
 Cutaneous nerve of the fupe- 
 rior extremicy, - 24S 
 
 Cutich, - - - 3 
 
 Cut.s vera, 5 
 
 Cyftic arte 1 -'/, - - 202 
 
 Cyftis fellis, - no 
 
 Dartos, 
 
 123 
 
 Depreflor oculi. 
 
 37 
 
 Diaphragm, blood- venels ot the 200 
 
 , nerves ot the 
 
 *53 
 
 Dorfal nerves, 
 
 *57 
 
 Drum of the ear, 
 
 47 
 
 Dutt, cyftic, 
 
 III 
 
 Duff, hepatic, - - no 
 
 — — , pancreatic, - 115 
 
 Dutfus communis cholidochus 112 
 Duodenum, 97 
 
 Dura mater, - g 
 
 , blood--, eflels of the 
 
 11.189 
 
 ■ ■ proceffes of the, 10 
 
 E 
 
 Ear, of the, 
 
 4+ 
 
 Epiglottis, - - - 63 
 
 — , fmall bones of the, 
 
 49 
 
 Ergot, or Hippocampus minor, 13 
 
 , mufcles proper to the, 
 
 45 
 
 Euftachian tube, - 48 
 
 Ear, external 
 
 44 
 
 Extre J luperior - fuperior 7 extre- 
 
 , mufcles of the, vol. I. 
 
 6o 
 
 mity, \ inferior •' inferior $ mity. 
 
 Ear, internal, 
 
 - 47 
 
 Eye, of the, - - 23 
 
 , mufcles of the, 
 
 5° 
 
 , coats of the, - 26 
 
 Eighth pair of nerves, 
 
 236 
 
 , humours of the, - 32 
 
 C olivares, ~j 
 
 
 , veffels of the, - 38 
 
 Eminentiae-c mammillares, 5* 
 
 21.22 
 
 , nerves of the, - 38.228 
 
 ( pyramidales, J 
 
 
 Eye and its appendages, arte- 
 
 Emulgent artery and vein. 
 
 207 
 
 ries or the, - 180 
 
 Epidermis, 
 
 3 
 
 — — veins of the, 186 
 
 Epididymis, 
 
 I2ZL 
 
 mufcles of the, 36 
 
 Epigaftric artery. 
 
 212 
 
 See alfo vol. I. 38 
 
 Face, lymphatics of the. 
 
 167 
 
 .b 
 
 Fifth pair of nerves, or par 
 
 , blood-vefiels of the. 
 
 185 
 
 trigeminum, - - 229 
 
 , nerves of the, 
 
 235 
 
 Firftpair of nerves, or olfaftory 227 
 
 Faix, or Septum cerebri, 
 
 IP 
 
 Follicles, lebaceous - 7 
 
 minor, or feptum cerbelli, n 
 
 Fornix, - - ig 
 
 Fat, - 
 
 8 
 
 F..iTa, or rivna mavna, - 133 
 
 Femoral artery. 
 
 214 
 
 FofTa navicularis, - 148 
 
 ■ ■ ■■ vein, 
 
 222 
 
 — — Sylv'n, ■ - 16 
 
 — — , or crural nerve 
 
 264 
 
 Fourth pair of nerves, or pathetic 228 
 
 Fibula-,- artery, 
 
 219 
 
 Frsenum lingua?, _ 59 
 
 ■ vein, 
 
 222 
 
 labiorurn pudendi, 138 
 
 
 266 
 
 preputii, - - 128 
 
 Call-bladder, 
 
 no 
 
 G 
 
 Ganglion femiiunare magnum, 239 
 
 Ganglia, » 
 
 226 
 
 Galtiic aueries, - 201 
 
INDEX 
 
 
 page. 
 
 Oaftric veins, 
 
 205 
 
 Generation and urine, Or- 
 
 
 g an s of, - 1 16. 1 CQ 
 
 , lymphatics of the 
 
 J S 7 
 
 — — — , blood -veflels of the 
 
 206 
 
 1 • , nerves of the. 
 
 261 
 
 Gland, lacrymal, 
 
 2 5 
 
 — -, parotid, 
 
 6l 
 
 — — — - , pineal, 
 
 19 
 
 • ■-, pituitary, 
 
 18 
 
 , proftate, 
 
 126 
 
 ■ , fublingual, 
 
 61 
 
 — — fubmaxillary, 
 
 ib. 
 
 Glands, arytenoid. 
 
 66 
 
 — — , axillary, 
 
 166 
 
 , bronchial, 
 
 87 
 
 
 155 
 
 — — — iliac, 
 
 1 58 
 
 — — , inguinal, 
 
 156 
 
 — — , lumbar, 
 
 lb. 
 
 — — , mefenteric, 
 
 160 
 
 — — — , miliary, 
 
 7 
 
 
 160 
 
 
 H 
 
 Haemorrhoid alis f media, 7 
 
 
 arteria, \ externa, y 
 
 214 
 
 ■ — —vena, 
 
 204. 
 
 Hairs, 
 
 7 
 
 Head, lymphaticson the outfide 
 
 166 
 
 , blood-vefiels of the, 
 
 J 75 
 
 Heart, of the, 
 
 74 
 
 . , abforbents of the. 
 
 164 . 
 
 Hellicis, j m ?J or ’ l 
 
 45 
 
 7 l minor, \ 
 
 
 Helix, 
 
 44 
 
 Hemifpheres of the brain, 
 
 !3 ' 
 
 Hepatic arteries. 
 
 201 
 
 Glands, renal, 
 
 -■ ■■ falivary, 
 febaceous, 
 
 , tracheal, 
 
 Glandulae ceruminofae, 
 
 concatenatae, 
 
 - Meibomiana •, 
 • odoriferae, 
 
 Gians penis, 
 
 . .. clitoridis, 
 Glolfo-pharyngeus, nervus, 
 Glottis, 
 
 Gluteal artery, 
 
 ■ nerves 
 
 page. 
 
 - 119 
 
 - 60 
 24 
 
 - 87 
 
 - 46 
 
 167 
 
 - 2 4 
 1 3 0 * 1 39 
 
 129 
 
 138 
 
 236 
 
 66 
 
 2x3 
 
 265 
 
 140 
 
 Gravid Uterus, of the, _ 
 Great fympathetic nerve, 238 ct seq 
 Gula, or gullet, - - 89 
 
 Gums, 57 
 
 Guftatorius, nervus, - 232 
 
 Gutturalis, artcria, J fu P er . ; ° r ’ 
 
 l inferior, igo 
 Gyri of the cochlea, - 51 
 
 Hepatic veins, 
 
 Hippocampus major. 
 
 Hole between the right auricle 
 and ventricle of the heart, 
 — — between the lateral ven- 
 tricles of the brain, 
 Humeral Artery, 
 vein, 
 
 Hymen, 
 
 Hypogaftric artery, 
 
 vein, 
 
 lymphatics, 
 
 nerves. 
 
 206 
 
 17 
 
 76 
 
 17 
 
 192 
 
 196 
 
 140 
 
 212 
 
 223 
 
 *59 
 
 261 
 
 I £*? 
 
 Jejunum, - "79 
 
 , latteals of the, 160 
 
 Iliac arteries and veins, 208.212.223 
 Ilium, inteftinum, - 80 
 
 Impregnation, changes produ- 
 ced in the uterine lyftem by, 142 
 Incus, - - 49 
 
 Inferior cava, - 223 
 
 Inferior extremity, lymphatics 
 of the, - 156 
 
 , blood- veffcls of the 2 1 1 
 
 . , nerves of the 262 
 
 Infra-orbitar artery, - 179 
 
 Infundibulum of the brain 18 
 
 — of the cochlea, 52 
 
 — — — — of the kidneys, 118 
 Integuments, common, - 3 
 
 Intercoftal arteries and veins, 120 
 
 nervesj - 237 
 
 Intestines, - 79 
 
 ■ — abforbents of the 159 
 
 Iris, - - 27 
 
 Ifthmus hepatis, - 108 
 
 ■ fau ium, * 63 
 
 VituJJinii , - 7® 
 
INDEX, 
 
 page. 
 
 page. 
 
 Iter ad tertium ventriculum, 
 quartum ■ ■ ■ ■ ■ , 
 
 Kidneys, 
 
 Labia pudendi. 
 
 Labial artery, 
 
 Labyrinth of the ear, 
 Lacrymal artery, 
 Lacteals, 
 
 Laftiferous dudts. 
 
 Lamina fpiralis, 
 
 Larynx, 
 
 Laryngea fnperior, artcria, 
 Laxator tympani. 
 
 Leg,— fee Inferior extremity. 
 Levator oculj, 
 
 Ligamenta, J J uteri 
 
 Ligaments of the liver, 
 Ligamentum fufpenforium 
 penis, 
 
 Lingual artery and vein, 171 
 
 Malleus, 
 
 Mammae, 
 
 Mammary arteries and veins, 
 
 Maffeteric arteries, 
 
 C dura 
 
 fee 
 
 Dura } 
 
 r 
 
 Mater, < ■ 
 
 ’ dP la 
 M atrix, 
 
 Maxillary artery, external, 
 . , — , internal, 
 
 -{! 
 
 fnperior, 
 inferior. 
 Meatus auditorius externus, 
 
 internus. 
 
 Median vein, 
 
 — nerve, 
 
 Mediaftinum, 
 
 Medulla oblongata, 
 
 Nails, 
 
 nerves of the 
 
 18 
 
 Jugular vein, external. 
 
 185 
 
 18 
 
 
 189 
 
 K 
 
 
 Il6 
 
 
 
 
 L 
 
 
 138 
 
 Lips, - 
 
 57 
 
 177 
 
 Liquor amnii, 
 
 346 
 
 Si 
 
 
 73 
 
 1S1 
 
 Liver. 
 
 106 
 
 153 
 
 
 161 
 
 70 
 
 — — , bloorf-velTels of the, 
 
 108 
 
 52 
 
 
 201 
 
 »4 
 
 
 2S9 
 
 376 
 
 Lobes of the brain. 
 
 !3 
 
 5° 
 
 of the liver. 
 
 107 
 
 
 — — of the lurgs, 
 
 84 
 
 37 
 
 Locus ni 0 ei- crurur-t cerebri, 
 
 21 
 
 
 Lumbar arteries, 
 
 2 1 1 
 
 > *34 
 
 
 263 
 
 107 
 
 Lungs, 
 
 84 
 
 
 — , lymphatics of the, 
 
 164 
 
 128 
 
 — — , blood-veflels of the 88 
 
 .174 
 
 ;.i86 
 
 — ... nerves of the, 
 
 254 
 
 232 
 
 
 
 M 
 
 
 40 
 
 Medulla fpinalis, 
 
 24I 
 
 68 
 
 Medullary fubftance of the 
 
 
 
 brain, 
 
 14 
 
 !.i 9 9 
 
 Membrana cellularis. 
 
 7 
 
 ib. 
 
 — pupillaris, - 27*147 
 
 179 
 
 Membrana tympani, 
 
 47 
 
 
 — lecundarii 
 
 1 S4 
 
 
 Meningeal artery, 
 
 178 
 
 133 
 
 Mel’enteric blood-veflbls, 
 
 202 
 
 177 
 
 nerves, 
 
 260 
 
 173 
 
 Mefentery, 
 
 IOO 
 
 186 
 
 Mefocolon, 
 
 ib. 
 
 23 1 
 
 Meforedlum, 
 
 ib. 
 
 232 
 
 Metatarf; 1 artery, 
 
 219 
 
 46 
 
 Modiolus, 
 
 52 
 
 51 
 
 Motores oculorum, or third 
 
 
 196 
 
 pair of nerves, 
 
 228 
 
 2CO 
 
 Mouth, of the. 
 
 57 
 
 72 
 
 Mufculo-cutaneous nerve of 
 
 
 21 
 
 the fuperior extremity. 
 
 2 49 
 
 
 N 
 
 
 6 
 
 Nerves, of the, 
 
 224 
 
 >•189 
 
 , cerebral, 
 
 227 
 
 2 45 
 
 
 245 
 
INDEX', 
 
 page. 
 
 Ninth pair of nerves, 
 
 238 
 
 Nipple, or papilla, 
 
 69 
 
 Noni defeendens nervus, 
 
 238 
 
 
 O 
 
 Obliquus oculi, ^ 
 
 37 
 
 Obturator artery, 
 
 213 
 
 nerve, 
 
 264 
 
 Occipital artery, 
 
 177 
 
 — vein, 
 
 186 
 
 OEfophageal arteries and veins 
 
 198 
 
 
 
 OEfophagus, 
 
 OEthmoidalis J anterior, 7 
 
 89 
 
 102 
 
 arteria, 5 pofterior, \ 
 
 Olfadlory, or fir ft pair of nerves 227 
 
 Omentum, or cawi. 
 
 IOI 
 
 Opthalmic artery, 
 
 180 
 
 
 P 
 
 Palate, 
 
 5 ^ 
 
 - — , arches of the, 
 
 62 
 
 Palat'ma inferior arteria, 
 
 177 
 
 Palmsru profunda arteria, 
 Palmar arch, deep, 
 
 294 
 
 a. 
 
 
 195 
 
 •= — - — - nerve, 
 
 252 
 
 Palpcbrs, 
 
 Pancreas, 
 
 Panniculus carnofus, 
 Pap of the throat, 
 
 24 - 
 
 314 
 
 9 
 5 8 
 
 Papilla, 
 
 6 9 
 
 Papillae of the tongue, 
 
 Par trigeminum, or fifth pair 
 
 £9 
 
 of nerves, 
 
 229 
 
 Parotid | ? 
 
 l g'and, J 
 
 6 1 
 
 Pars vaga of the eighth pair 
 
 
 of nerves, - 236.254.259 
 
 Pathetic, or fourth pair of nerves 228 
 
 Pedes hippocampi, 
 Peduncuii of the brain and 
 
 17 
 
 cerebellum, 
 
 21 
 
 Pelvis, lymphatics of the 
 
 158 
 
 — — , blood-vefiels of the 
 
 211 
 
 , nerves of the 
 
 262 
 
 Penis, 
 
 128 
 
 — , lymphatics of the 
 
 *57 
 
 , blood-vefl'els of the 
 
 208 
 
 — •, nerves of the 
 
 261 
 
 Pericardium, 
 
 73 
 
 page. 
 
 Nose, of the, - 40 
 
 Nymphs, - - 139 
 
 Opthalmic vein, - 188 
 
 nerve, - 229 
 
 Optic, or 2d pair of nerves 31.228 
 Orbiculare, os, - 49 
 
 Organs of the fen fes, 3 
 
 —————of urine and generation 
 
 in the male, 116 
 
 in the female, - 132 
 
 lymphatics of the 157 
 blood-vcfi'els of the, 206 
 nerves of the, - 261 
 
 Os tincse, - - 134 
 
 Ova 1 
 
 Ovaria, J ” *35 
 
 Perineum, 
 
 Peritoneum, 
 
 Peroneal artery. 
 
 Pharyngeal artery, 
 
 Pharynx, 
 
 Phrenic nerve, 
 
 Pia mater, 
 
 Pinguedo, 
 
 Placenta, 
 
 Plantar artery and arch, 
 Pleura, 
 
 Pomum Adami, 
 
 - 
 
 Popliteal artery, 
 
 — — - vein, 
 
 Ports, vena, 
 
 Portio SmoUis^oftheythj 
 Lams, i pair, 1 
 Prepuce of the penis, 
 
 — of the clitoris, 
 
 Profunda femoris, arteria, 
 vena, 
 
 -humeri arteria, 
 -penis arteria. 
 
 Pfalterium fornicis, 
 Pterygoideae arteriae, 
 Pudendum, 
 
 Pudic artery, 
 
 138 
 
 92 
 
 219 
 
 266 
 
 r v 
 
 6 3 
 253 
 
 12 
 
 8 
 
 145 
 
 220 
 
 71 
 
 64 
 
 227 
 
 223 
 
 205 
 
 2 33 
 
 128 
 
 139 
 
 215 
 
 22a 
 
 19a 
 
 210 
 
 17 
 
 179 
 
 200 
 
 aio 
 
INDEX. 
 
 Pudic nerves, 
 
 pulmonary artery and veins, 
 
 Radial artery, 
 
 ■■ nerve, 
 
 Ranina arreria, 
 
 . vena, 
 
 Receptaculum chyli, 
 Reftum, 
 
 — — , lymphatics of the, 
 
 page. 
 
 261 Pupil of the eye, 
 
 174 Pylorus, 
 
 R 
 
 193 Recurrent nerve of the eighth 
 
 pair, 
 
 radial artery, 
 
 ulnar artery, 
 
 Renal artery and vein, 
 
 194 
 
 176 
 
 1 '36 
 
 90 
 
 9 S 
 
 *59 
 
 nerves, 
 
 Retina, 
 
 pagt. 
 
 27 
 
 . 95 
 
 2 54 
 
 193 
 
 194 
 207 
 261 
 
 3 * 
 
 Sacral artery, 
 
 ■ - lateral arteries, 
 
 nerves. 
 
 Salivary glands, 
 
 Saphaer.2, vena, 
 
 r ’ ’ 1 minor, 
 
 Saphaenus, nervus. 
 
 211 Soermatic artery and vein, 125.207 
 
 213 
 
 265 
 
 60- 
 
 221 
 
 264 
 
 srd, 
 
 nerves, 
 
 Sphin&er reficse, 
 
 Spinal Marrow, of the, 
 — — — nerves, origin of the, 
 Spinalis dorii, fee vol. I. 
 
 125 
 261 
 121 
 241 
 ib . 
 86 
 
 Scala $ t y ra P ani ’ X 
 
 
 Spiral nerve, 
 
 249 
 
 bcata ’ l vefcibuli, J 
 
 S z 
 
 Splanchnicus nervus, 257 
 
 .259 
 
 Scaoular arteries, 
 
 192 
 
 Spleen, 
 
 1 12 
 
 ■ nerve, 
 
 248 
 
 , lymphatics of the, 
 
 162 
 
 Sciatic artery. 
 
 214 
 
 Splenic artery. 
 
 202 
 
 Sciatic nerve, 
 
 266 
 
 Splenicvein, 
 
 204 
 
 Sclerotic coat, 
 
 28 
 
 — — ■■ nerves, 
 
 260 
 
 Scrotum, 
 
 122 
 
 Spongiofum, corpus, urethras. 
 
 I29 
 
 Sebaceous dudts, 
 
 7 
 
 Stapedius, 
 
 5 ° 
 
 Second pair of nerves, or optic, 
 
 201 
 
 Stapes, 
 
 49 
 
 Secundines, 
 
 144 
 
 Stomach, 
 
 02 
 
 Semicircular canals of the coch- 
 
 
 — — , abforbents of the 96.161 
 
 lea, - 52 
 
 Semilunar ganglion, - 259 
 
 Seminal veflels, - - 126 
 
 Senses, Organs of the, 3 
 Septum cerebri, or falx, - 10 
 
 Septum cerebelli, - 11 
 
 " lucidum, - 16 
 
 ■■ penis, - 129 
 
 — - ■ fcroti, - 122 
 
 Seventh pair of nerves, - 233 
 
 Sinufes of the dura mater, 12.188 
 
 Sixth pair of nerves, 
 Skarf-lkin, 
 
 Skin, 
 
 262 
 
 , blood-veflels of the 93.200 
 
 — ■ ■, nerves of the 96.259 
 
 Sublingual artery, - 176 
 
 Submental artery, - 177 
 
 Suboccipital nerves, - 245 
 
 Superbus, - 37 
 
 Supercilia, - 23 
 
 Superior cava, - 199 
 
 Superior Extremity, 
 
 • , lymphatics of the, 
 
 — — — — , blood-veflels of the, 
 nerves of the. 
 
 Supra-orbitar artery, 
 Sympathetic nerve, 
 
 i6 5 
 190 
 
 s 45 
 182 
 238 etfej. 
 
 Taenia hippocampi, - 17 
 
 • femicircularis of Haller, 16 
 Tarfea arteria, - 218 
 
 Tarfus of the eye-lids, - 24 
 
 Tela choroidea, - 17 
 
 Temporal artery, 
 
 Tenfor tympani, 
 Tentorium cerebelli, 
 Teftes, 
 
 *79 
 
 185 
 
 5 ° 
 
INDEX, 
 
 „ page. 
 
 Teftes, lymphatics of the - 158 
 
 — ■ — , blood-veflels of the 125.206 
 — nerves of the 261 
 
 Thalami nervorum opticorum 15 
 Third pair of nerves, or mo- 
 
 tores oculorum, - 228 
 
 Thoracic du ft, - 90.163 
 
 Thorax, of the, - 68 
 
 ■ ■ , blood-veflels within the 197 
 
 — — , nerves within the 
 Throat, of the, 
 
 ' inferior, 
 
 253 
 
 62 
 
 Thyroidea arteria ^ 
 Tibial arteries. 
 
 fuperior. 
 
 190 
 
 176 
 
 218 
 
 Tonfils, 
 
 Torcular Hemphill, 
 Tradfus optici, 
 
 Tragicus, 
 
 Tragus, 
 
 Tricufpid valve, 
 Trochlearis, 
 
 Tuber annulare, 
 Tubercula quadrigemina, 
 Tuberculum, Lotveri, 
 Tubes, Eujiachian , 
 
 — — — , Fallopian, 
 
 Tunica albuginea, 
 
 arachnoidea. 
 
 page, 
 
 6 3 
 12.188 
 16 
 45 
 - 44 
 77 
 37 
 z'j 
 
 J 9 
 76 
 48 
 * J 35 
 123 
 12 
 
 — veins, 
 
 221 
 
 aranea, or vitrea. 
 
 35 
 
 nerve, 
 
 266 
 
 choroides. 
 
 29 
 
 Tomentum cerebri, 
 
 *3 
 
 , fclerotica. 
 
 28 
 
 Tongue, of the, 
 
 59 
 
 ■■ vaginalis, 
 
 123 
 
 — - , lymphatics of the 
 
 167 
 
 Tympani laxator. 
 
 5 ° 
 
 1 , blood-veflels of the 
 
 176 
 
 Tympanum, 
 
 47 
 
 , nerves ot the. 
 
 232 
 
 
 
 
 U & V 
 
 
 Vagina, 
 
 136 
 
 Vermiform appendix of the 
 
 
 Vaginal artery, 
 
 209 
 
 c cecum, 
 
 104 
 
 Valves of the abforbents, 
 
 i >4 
 
 Vermiform appendages of the 
 
 
 
 173 
 
 cerebellum, 
 
 20 
 
 
 76 
 
 Veflca urinaria, 120- 
 
 -I32 
 
 Valvulacoli, 
 
 ICA 
 
 A^eficalis ima arteria, 
 
 214 
 
 Vafa brevia, - 202.20c 
 
 Veficula fellis, 
 
 I IO 
 
 » efterentia of the teftes, 
 
 126 
 
 Vcftible of the labyrinth, 
 
 5 1 
 
 5 efterentia, 1 of the ab- 
 
 
 of the pudendum, 
 
 139 
 
 £ inferentia, y lorbents. 
 
 155 
 
 Viscera, of the, 
 
 3 
 
 la aea 5 P rimi ’ ?& ene ‘ 
 
 
 Vitreous humour. 
 
 34 
 
 ' £ lecundi, 5 ris. 
 
 160 
 
 Ulnar arteries, 
 
 194 
 
 Vafavaforum, 
 
 I70 
 
 - nerve, 
 
 25I 
 
 Veins, of the, 
 
 I72 
 
 Umbilical cord, 
 
 144 
 
 Velum Vieujfenii , 
 
 20 
 
 artery. 
 
 208 
 
 Vena cava, general courfe of the 
 
 174 
 
 Volar arches, 
 
 195 
 
 - ■ — luperior, 
 
 199 
 
 Vorticofe veins, 
 
 186 
 
 , inferior, 
 
 223 
 
 Ureters, . - 119 
 
 • J 33 
 
 Vena magna ipfius penis, 
 
 210 
 
 Urethra, - 130.139 
 
 Vena portae, 
 
 205 
 
 Uterus, of the, 
 
 133 
 
 Ventricles of the brain. 
 
 15 
 
 . — appendages of the, 
 
 134 
 
 of the heart, 
 
 76 
 
 Uvula, 
 
 5 * 
 
 43 
 
 Zonula ciliaris- 
 
4