A Treatise on Farriery. 193 twelve grinders or double-teeth,, feventeen joints of the back have that is, fix on each fide. The lower jaw is moveable and is articulated into the lower part of the temporal bone. It is round and fmooth on the lower edge, and hollow within, containing cells filled with marrow; | the middle or fiat part is more folid. The fockets of the teeth are the fame in number as in the upper jaw. pafs Several blood - veffels through the feams of the fcull, and through holes and perforations in feveral parts of the skull; thefe carry the blood to and from the brain and its membranes. There are likewife feveral paf. fages for the nerves, all which are beft feen in the fkull of a horfe. There are feveral impreffions and furrows on the infide of the bones of the fkull, and which are made by the arteries of the dura mater, a membrane that en wraps the brain. When the bones of the skull are quite grown, no common faw will touch them; by which means a horfe's head is well defended against external injuries, unless it be towards the nofe, for that part confifts of more fpungy bones and cartilages which are extremely fenfible and tender. The bone of the tongue is like a Greek v, and ferves for the insertion of the feveral mufcles of the head or palate and wind-pipe. The vertebra or bones of the back are thus numbered; the neck has seven, the back feventeen, the loins feven, the croup, fix, and the tail eighteen. The fpines of the bones of the neck are round, and fmooth, with a hollownefs between them on each fide. The uppermost has a process whach is received into the fecond, and on which the head turns as on a hinge. The very high fpines, efpecially on the withers, which rife archwife, and are united by a strong ligament, The fpines are shorter along the withers, till they ap proach the loins, where they rife higher. But behind they are more level as they approach towards the rump. All thefe have large holes, through which the marrow of the back paffes from the brain to the rump. The bones of the tail are not perforated, being without marrow. They are fpungy, and joined together" by foft griftles. They are largest at the rump, and leffen gradually till they end in a point. The collar bones are one on each each fide, fhaped like an . They are united at one end to the upper part of the breaft-bone by little heads which enter into the cavities, and to the uppermoft rack-bone of the back. They ferve to fupport the bladebones, and to keep them from fliding forward. The ribs are diftinguifhed into the true and falfe, and are 34 in number. The true and nearest the fhoulders, and are nine in number on each fide, which are joined to the rack-bones of the back. The baftard or falfe ribs are eight on each fide; they are not so hard and ftrong as the true ribs, and grow fhorter as they approach towards the flanks; they are all thick towards the back, but thin and flat on the other end. When the ribs are large in compass, a horfe's belly looks more round; but when they are fhort a horfe's belly has not that afpect which gives a general fatisfaction, nor does the animal breathe fo freely. They are very smooth on the infide, being covered with a membrane extremely fine. The 194. A Treatise on Farriery. The breaft-bone is shaped fomewhat like the bottom of a hip, and has cartilaginous dents where it receives the lower end of the true ribs. That part next the pit of the ftomach is called the fword-like cartilage, becaufe its point resembles a fword. an The blade-bone of the fhoulders runs from below the whithers to the point of the fhoulder-bone, which laft turns backwards towards the elbows, making acute angle with the former. The blade-bone is joined to the ribs by muscles which have very frong tendons. In the lower end there is a fhallow cavity, which receives the head of the houlder-bone. It is furrounded with a tough cartilaginous fubftance, and is covered with a broad ftrong ligament, which not only prevents the fhoulder-bone from flipping out, but renders the motion of the fhoulder easy, and fit to play in all the neceffary directions. The Shoulder-bone is fhort and reaches to the elbow, where it joins to the bone of the fore-leg by very strong ligaments. It has two proceffes at the lower end, between which a high process of the leg bone enters, which makes the elbow joint; and the high fender procefs of the leg. bone makes the elbow. This rifes higher than the joint, and hinders the leg from turning backward. The leg-bone is joined to the fhank bone, which are received into each other. This joint makes the knee, and has two ranks of little bones within the bending of the knee, three in the firft, and four in the fecond, which ferve to render the motion fafe and easy. They are united together by ligaments, which are partly tendinous, and partly cartilaginous. The shank bone reaches from the knee to the great paftern, and is compofed of three bones, one of which is large, and the others fmall. The laft are thick and round upwards, and fmall downwards. The great paftern has three small proceffes which are received into three cavities of the fhank bone. The great paftern has likewise two cavities, which receive the procefs of the shank-bone. On the back part of the great paftern, two triangular bones are fixed, which form the fetlock, and ferve to fuftain the joint in its regular motion, preventing the falfe. The little paflern, or coronary bone, is fo clofely united with the great paftern, that they feem to be one before examination. The lower end of the little paftern is articulated with the coffin or foot-bone, between which behind is placed the nut bone, fo called by Monfieur la Foffe, and which is omitted by Gibson. The little paftern is reduced into the great by two heads, and into the coffin-bone in the fame manner. The coffin-bone is fo called, becaufe it lies within the hoof, as in a coffin. It is round on the upper part, where it receives the little paftern or coronary bone, but grows broader and thinuer toward the bottom. It is of a porous fubftance, and may be eafily pierced by nails or other fharp things that are trod upon. The nameless bones are feated on the hind part of a horfe, and are divided into the haunch, the hip, and the harè bones. The flat fides of the hip-bone form the hip, with the mufcles that are placed in the hollow of them. The A Treatise on Farriery. The haunch bones, which some call the os pubis, make a small arch at the extremity of the lower belly, through which the yard paffes, at the entrance of which is the neck of the bladder. The hare bones, termed in Latin the ifchium, have a round cavity on each fide which receive the head of the thigh bone. The back or upper part of these bones are joined to the os facrum by cartilages or griftles, which in time turn almost into bones. The bone called the os facrum lies under the crupper, next the rump; which, with the nameless bones, form the pelvis or bafon. It is joined to the lowest rack-bone of the loins, and to the uppermost bone of the rump The thigh bone has a round longifh head, called by fome the whirl bone, which enters the cup of the hip-bone, and on which it turns backward and forward. The lower end of the thigh-bone has two proceffes, like a pully between which there is a large fpace which receives the protuberance of the leg-bone. Between the thigh-bone and the leg-bone there is a hollow that receives the title-bone, which aufwers to the knee-pan of a man. It is prominent on the outfide, and rough where the mufcles of the thigh are in ferted, and curved and smooth on the infide. It is kept in its place by a strong ligament which rifes from the upper end of the leg-bone, and is inferted into its lower end: as alfo by the tendons of the mufcles of the thigh, which are inferted into its upper end: together with a ftrong liga mentous fubftance which is expanded all over it. It is very ftrong and folid, like a piece of flint, and has no cavity. 195 The Small bones of the hock are placed in two ranks, like those of the knee; the first confists of three, and the fecond of four, which are articulated into the inftep. They are smooth to facilitate the motion of the joint, and ferve to keep a horse's legs from doubling under him. The inftep confifts of three bones clofely united, which appear as one. The paftern and coffinbone differs in nothing from thofe of the fore-feet. The hoofs are made up of hufks, which cover the pyradimal papillæ of the fkin, which lie clote upon one another. They are without sense, that the horse may the better encounter the roughness of the road. When they are paired or cut, they always grow again. They are fastened to the coffin-bone by a ligiment which furrounds it below the coronet, like a piece of tape. Underneath the hoofs are many twigs of tendons, nerves, and mufcles, which run to the bot. tom of the foot, making the fubftance which lies beneath the foul and the coffin-bone. All the long bones are hollow in the middle, being filled with marrow, and porous at the extremities; over which they have an epiphyfis or griftly cap, to render the motion of the horse free and eafy; there are likewife glands in the joints, which feparate an oily matter, which always keeps them flippery, and prevents their wearing. OF THE MUSCLES. THE mufcles have been defined before, and are well known to be the inftruments of motion. They have long been the fubject of an elaborate enquiry in a hu man body, and for that reafon 196 A Treatise on Farriery. have obtained particular names But as thefe are wanting in a horfe, we can only at prefent defcribe them by their ufes. And this, if duly attended to, will answer all the purposes of thofe who out of curiofity examine into the nature of a horse, or who have undertaken the more arduous task of curing their difeafes, efpecially in cafes wherein the mufcles are principally effected. eyes. widen and contract the nostrils: which action is most apparent when horfes are moft heated with exercife, when they are brokenwinded, and when they have a fever. When the working of the noftril is violent, the upper-lips is drawn upwards at the fame time. The lips have five pair of mufcles that are proper, and two common to the mouth and cheeks; one pair of these ferve to draw the fuperior lip directly. Befides, there is a eyeremarkable muscle which belongs to the lips, and affifts in all the motions of the jaw, and has a very strong action; for which reafon, it arifes partly from the vertebre of the neck, partly from the fhoulder-bone, breaft-bone, and collar-bone, and is inferted into the chin, lips, and lower part of the nofe. The remainder, which direct the motion of the lips, arise from the upper and lower jaw, and are inferted into the fphincter mufcle, which furrounds the extremity of the lips. We fhall begin with the mufcles of the eye-lids and The lids have one pair of mufcles, which ferve to open them, and two to fhut them. That which is employed in opening them, is peculiar to the eyelid; whereas the other two, whofe ufe is to bring them together, or fhut the eye, is inferted into both. They all have their rife from the edge of the hole in the bottom of the orbit, through which there is a paffage for the optic nerve. The mufcles in the forehead have fome fhare in these actions, which may be perceived when the horse is brought out of a dark place into the light. The eye has feven pair of mufcles to perform the variety of motions which that organ requires. They have fix of these in common with men, and have their rife from the fame part as the former, as alfo the feventh, which is peculiar to animals that feed with their heads downwards, and ferve to fufpend the eye, keeping it from projecting too far outwards. It is fhort and flefly, and is inferted into the hinder part of the cornea. The nofe has four pair of mufcles, which rife from the upper jaw, and from under the eyes. They are all inferted into the griftles of the noftrils, and part of the upper lip. They ferve to The mufcles belonging to the lower jaw, are the temporal muscles, which compofe the fleshy part of the temples, which ferve to fhut the mouth, and the abovementioned ftrong mufcle which is inferted into the chin and upper-lip, which helps to pull down the jaw, and open the mouth. The maffeter muscles are used in chewing; and there is one pair that pull the jaw forwards, and another backwards. *** To give our Readers a clearer idea of our obfervations on the bones, &c. we beg leave to prefent them with the annexed highly finished ENGRAVING of the SKELETON of a HORSE.. (To be continued.) To |