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ANATOMY OF THE HORSE. 
Of the External Parts. 
The Hoof : 
The hoof is the horny case, or covering, nature has provided 
for the protection of the sensitive parts of the foot. It may be 
said of itself to constitute such a shoe, or defence, as enables 
the animal in his wild state to travel about in quest of food, not 
only without injury to the structures underneath it, but with a 
degree of elasticity that preserves his whole frame from concus¬ 
sion. Were one forced into any comparison of the sort, it must 
be admitted that the hoofs of animals bear some anatomical 
affinity to the human nails, or claws of other animals; though 
they are vastly superior in physiological importance to any such 
appendages as these. 
Form .—Sainbel viewed the foot as “ the segment of an oval, 
opened at the back, and nearly round in front.” To a common 
observer, the hoof exhibits a conoid form; the part resting upon 
the ground being the basis—the vacuity above, the obtruncated 
apex. Mr. Bracy Clark avers that this view is incorrect, and 
that the general figure of the hoof is a cylinder , very obliquely 
truncated upon its ground surface. This he demonstrates in two 
ways; either by rolling up a piece of paper into the shape of a 
cylinder, and afterwards cutting one of its ends in a very slanting 
direction; or by taking a carpenter’s square, and placing one 
limb beneath the foot across the quarters, then sloping the other 
backward against the side of the quarters, parallel to the front, 
when the edge of the iron will be found parallel to the wall of 
the hoof. This corrected view of its figure will serve to account 
for the general equiformity manifest in the hoof, and also for the 
undeviating correspondence found to exist between its slope, or 
slant, as well in front as behind, which in an ordinary or healthy 
foot may be estimated at an angle of 45°. Around the coronet, 
where the hoof unites with the skin, the cylinder is cut directly 
across its perpendicular—at right angles with it: it is the oblique 
truncation of its ground-surface that occasions the slant, which 
latter we may consequently increase at pleasure by any means 
that augment the former, viz. by lowering the heels; by cutting 
away a prominent frog ; or by putting on thin-heeled shoes. At 
the same time that we increase the slant of the hoof, we increase 
the obliquity of the pasterns, and likewise proportionately aug¬ 
ment the ground-surface of the hoof, from heel to toe, the breadth 
remaining unaltered; and in the same ratio, consequently, ex¬ 
tend the surface of tread*. 
* For further elucidation on the cylindrical form of the foot, consult 
Mr. Bracy Clark’s works on the Foot of the Horse. 
