F A R R 
palling from the point of the fcapula in an oblique direc¬ 
tion backwards j and inflead of partaking of the various 
motions of the above bone, poffeffes but one motion, that 
of being brought from its inclined pofition forwards to 
the perpendicular line of the body. This bone polfelles 
various ftrong elevations and depreflions for the lodg¬ 
ment and infertion of mnfcles, of which there are hardly 
any traces in the bone of the human arm. It articulates 
inferiorly b'y two ftrong condyles with the radius. The 
fore-limb of the horfe not requiring any rotatory motion, 
as in the human arm, we find no diftinft os ulna, but the 
point of the elbow, or olecranon, being very much en¬ 
larged and extended in length, is firmly fixed to the back 
of the radius, fending off a procefs of bone downwards, 
which is brought to a point about the middle of the ra¬ 
dius, uniting firmly with it j from iis pofition being fixed 
in refpeft to the radius, it can perform but one of the 
offices of the human ulna, and ferves for the attachment 
of thofe nmfcles which bring back the fore-arm from its 
bent pofition Towards, to the firaight line, under the 
prefiure of the weight of the body. 
The bones of the carpus , called the knee of the horfe, 
correfpond to the bones of the human wrilt; thefe bones 
do not afford a fimilur extent of motion with the lame 
bone in the human carpus, not admitting any motion for¬ 
ward beyond the perpendicular line, nor of any lateral 
motion whatever. On a firft view of the bones of the 
knee of the horfe, their pofition feems reverfed to the hu¬ 
man wrift, the olecranon or elbow being placdd at the back 
of the radius, and the flexion taking place in a direction 
towards it; and the boneswhich form the back,of the 
wrift: appear to form the front of the knee. This inver- 
fion, however, is only apparent, and not really fo, as by 
a flight rotation of the radius, the human wrift may be 
placed in the fame relative pofition to the ulna, as the 
bones of the knee of the horfe are with refpeft to it. The 
carpus is made up of feven bones, fometimes eight, a very 
j'rnali round" bone being often fuperadded on the fide, 
about the fize of a pea, hut is not noticed in the gene¬ 
rality'of the fkeletons of the horfe. This joint is formed 
of two regular layers' or phalabges of bone, the upper 
phalanx or row being placed upon and between the divi- 
fions of the other three in each phalanx, the feventh being 
thrown behind. The firft layer, viz. that placed on the 
cannon-bone, has little or no motion ; the fecond layer has 
confiderable motion on the firft, as thofe have alfo on the 
radius, making in their total flexion about thirty degrees 
of a circle. To ftrengthen this joint, and to fecure thefe 
bones more firmly in their fituations, they are formed with 
alternate elevations and depreflions both in their upper and 
lower furfaces ; this joint is alfo rendered ftronger from 
having an articulation, which admits of motion in one 
direction only, that of flexion, and that in the oppolite 
direction to the fiexionof thehock, tending by this means 
to give the ftrongeft mechanical fupport to the animal. 
The weaknefs of this joint, called knuckling, does not ap¬ 
pear to proceed from any defeat of the joint ilfelf, but 
from the rigidity of thofe mnfcles which ferve to bend if, 
and efpecially thofe which pals to the foot; the exten- 
fors, which are comparatively filial 1, not having luffi- 
cient power to counteraft it. 
The great difference of proportion in the parts which 
compofe this fore extremity to that of the human, is no 
where more confpicuous than in the metacarpal bones. 
The range of bones which form the wide palm, or the 
paws, of animals, is here for the principal part condenfed 
into one folid cylindrical bone, longer conflderably than 
the humerus it felf, the rudiments conflderably abbreviated 
oi the two exterior metacarpal bones remaining to point 
out the general connection among quadrupeds. The 
ftiank bone is flattened pofteriorly for the reception of the 
fiifpenfory ligament and tendons going to the foot, which 
is more confiderable in the fore extremity than in the 
bind one; the latter being longer, and of a more cylin¬ 
drical figure. The ftyloid, or fplint bones, adhere to the 
I E R Y. 227 
fliank very ftfongly, and are moftly united to it by oflific 
depofitions, otherwife every where preferving a divided 
outline between the two bones. In the fore Extremity 
thefe moftly dwindle to a point, about two-thirds down 
the length of the fhank bone, and are not lb-large as in the 
hind extremity. Thefe fplint bone^, though often pro¬ 
ductive of difeafe, tend to ftrengthen the joint laterally ; 
and perhaps by their yielding to the perpendicular pref- 
Iure of the limb, may aft as cufhions in a flight degree 
in preventing concuffion ; they alfo ferve to ftrengthen 
the limb, by affording a furface for ligamentary attach¬ 
ments. The inferior extremity articulates with the paf- 
tern bone by a condyle, having an elevated ridge of bone 
in the middle to fupport it, which enters a correfponding 
depreffion in the pattern bone. This joint, though ftrongly 
fortified with ligament and tendon, is more fubjeft to Iitf- 
fer from violent uft.ge than any other in the body. In 
the cloven-footed horfe of Chili, the divifion begins in 
this part. See the article Equus, vol. vi. p.885. 
The fifamcid bones are placed at the back of the pattern 
joint, and referable in their figure and properties, the fame 
bones in the human foot ; diminiftving friftion, powerfully 
affifting the tendons going to the foot, and at the lame 
time fupporting the pattern joint by their preffure. The 
os fvjf'ragineum, or pattern bone, correlponds to the firft 
phalanx of bones of the fingers, the five bones of which 
may be conlidered as confolidated into one fi-ngle bone ; 
its general figure refemble's fufficiently a bone of this part. 
The pattern bone, at either end, is indented for the re¬ 
ception of the prominent condyles of both the lhank and 
the coronet. The os corcn<e, or coronet bone, is, like the 
former, a fimilar condenfation of the five bones of the 
fecond phalanx of the fingers, and is proportionably 
Ihorter ; it articulates by a divided condyle with the 
coffin bone. This and the preceding are rough on their 
fides, with depreflions for the ftrong infertion of ligament, 
efpecially laterally, in the point of the axis of the condyle, 
where a deep indentation is obfervable. The os blips, or 
coffin bone, forms a diftant refemblance witii the enlarged 
rounded point of the extremity of the bone of the finger. 
The particular ftrufture of thefe hones, and their various 
appendages and integuments, are (hewn under the deferip- 
tion of the foot. 
Of the hind extremity. —The femur, or thigh bone, 
of the horfe, compared with the human, is remarkably 
lliort, fo as fcarcely to appear beyond the parietes of the 
abdomen externally. This bone is of vaft ftrength, pof- 
feffi.ng feveral elevated and deprefled points for the ftrong 
infertion of tendons and mufcles, which ferve to dittin- 
guifh it from the thigh bone of every other animal. The 
head of this bone in the human fubjeft is carried by an 
oblique procefs, or neck, to a diftance from the bone, 
whereas, in the horfe, the head is without any length of 
procefs of this kind, placed at right angles nearly to the 
hone, not affording that variety of motion which the hu¬ 
man ftrufture of this part does ; a motion directly back¬ 
wards and forwards being for the molt part the only 
movement requifite for the horfe. In a ftate of reft, the 
thigh bone is not nearly in the perpendicular line of the 
body, asin the human thigh, but inclines forward, making 
an angle with the body of about forty-five degrees, and 
forms pofteriorly an obtufe angle with the reft of the ex¬ 
tremity. This circutnftance is neceffary to be obferved 
with attention, previoully to ur.derftanding the delign of 
the mufcles of this extremity. Thofe which are attached 
to the pofterior part of this bone are called its exteniors, 
ferving to draw it from the oblique line it deferibes for¬ 
wards, backwards to the perpendicular of the bod)', being 
attached near its head, and rather laterally. Thofe mut- 
cles alio which render this angle more acute, by drawing 
it fot wards under the belly, are called its flexors, and are 
attached to its anterior fuperior part. The great trochan¬ 
ter oi the horfe, riles conflderably above its articulation 
with the acetabulum. The letter trochanter in the human 
thigh is placed ahnoft behind it, but in the horfe laterally 
internally. 
