36 
REVIEW. 
Bracy Clark's Theory of the Elasticity of the Hoof. 
“ Elasticity,” according to Bracy Clark, “ is the inestimable 
property that guarantees the foot from fatigue, preserves it 
from jar, and the body from re-action and concussion, and all 
the injuries which a too solid resistance would have occasioned 
to both, and probably assisting also the animal in his advances 
by a return to its former figure after distention*.” 
In demonstration of its elastic property, as a whole, Bracy 
Clark commences by resolving the hoof into three constituent 
parts; a division that had not been made, says M. Bouley, 
before, and therefore one which he, with justice, claims as his 
invention. 
“ In order to illustrate these subjects” (the arts of shoeing, 
its difficulties and mysteries), we quote from Bracy Clark, “ we 
shall divide the hoof into its constituents of three distinct parts, 
which has not been attended to before; and view them after¬ 
wards connectedly, to shew that they produce by their com¬ 
bination not only a box of horn for the covering the foot, as it 
has been hitherto generally regarded, but also a most beautiful 
machine, possessing remarkable properties, and an almost in¬ 
definite power of yielding to the load, a property as indis¬ 
pensable as the defence and protection that it so obviously 
affordst.” 
To this we append—what M. Bouley had it not in his 
power to supply, from not being in possession of, indeed, we 
may say, from never having even seen, Coleman’s work on the 
Foot— 
Colemans Theory of the Elasticity of the Hoof, 
which runs as follows:—He asserts, that the weight of the body 
is sustained within the hoof by the laminae, not by the sole 
and frog, though the sole receives secondary impulse from it, and 
the frog also each time it receives pressure from the ground;— 
that the laminae, from their elasticity, admit of the descent of 
the coffin bone, downwards and backwards; and that the coffin 
bone in this motion forces down the sole. That at the same 
moment that the sole is pressed down, the frog, by the pressure 
it receives from the ground, is forced upward, against the fibro¬ 
cartilaginous substance above it. This being rendered broader 
by the compression, dilates the lateral cartilages, which in con¬ 
sequence of such dilatation expand the heels, and impart a 
tendency to the newly-formed horn at the coronet to take an 
* Hippodonomia, p. 27. f Hippodonomia, p. 31. 
