44 
THE ANATOMY OF THE HORSE. 
may be said to be represented by the perpendicular line extend¬ 
ed through the middle of the square : the angular position of 
these bones renders their motions more extensive and facile, at 
the same time that they, so placed, present convenient and 
powerful levers for the operation of the muscles. Furthermore, 
the bones forming the limbs are, superiorly, lengthy and few in 
number; whereas, below the fetlock, they are small and consist 
of sevei'al pieces : the rationale of which is, that the long bones 
are well adapted for extent of motion ; the short ones, for re¬ 
sistance and multiplicity of movements. The head and neck 
operate as a burden, in addition to half of the trunk, upon the 
fore limbs ; although the hind limbs appear the greatest and 
most capable of resistance : this apparent incongruity is remov¬ 
ed when we come to learn that the latter constitute the power¬ 
ful engines of progression. 
Of the multiplicity and variety of pieces or distinct bones of 
which the skeleton is composed, most are found to be double, 
or to exist in pairs; such are the ribs, most of the bones of 
the head, and all those of the limbs: there are however several 
single bones ; and these may be regarded as the key-stones of 
the fabric, being in reality the media through which the 
two lateral halves of the skeleton (composed of the bones in 
' pairs) are united together into one entire structure. In this 
arrangement, the symmetry of the whole is preserved most 
completely, even as completely as if every bone had had a 
fellow; since both sides of the single bones exactly corres¬ 
pond. 
The bones so far influence and determine the form of the soft 
parts that in very many (perhaps the majority of) instances, 
the animal is recognised in the appearance of the skeleton ; in 
other examples however this is not so remarkable ; in all the re¬ 
semblance can be traced only in certain parts. In general, the 
head, chest, and legs—below the knees and hocks, present 
striking outlines of the same parts in the living animal; where¬ 
as, the rteck, loins, arms, and haunches, have few or no points 
of similitude. 
Division. THE SKELETON is composed of 238 bones, 
and is divided into trunk, head, and extremities. 
The Trunk is subdivided into spine^ thorax, Viiidi pelvis. 
The Head comprises the cranium and the face. 
m 
The Extremities are four in number: two ybrc and two 
hind. 
