45 
THE HORSE’S FOOT. 
for several months without having his feet trimmed and pared by 
the blacksmith, these are seen contracting by degrees, as they in¬ 
crease in length, and soon assume the aspect of hoof bound. 
But these are not the only effects of shoeing in the etiology 
of contraction. On the contrary, this practice is the most 
common cause of this lesion of the hoof, if not practiced with 
the intelligence it requires. We have said, in speaking of corns, 
that they were proofs of bad shoeing. The same might be said 
of the contraction. Moreover, corns generally indicate great 
errors in shoeing, while hoof bound demonstrates the ignorance 
of the physiology of the hoof, which in action must enjoy the 
necessary elasticity to relieve the contact with the weight 
of the body upon the ground. No doubt the theory of 
Bredey Clark exaggerates the degree of elasticity in admitting a 
great power of dilatation of the hoof, but it is an opposite excess 
to deny it entirely. The dilatation of the hoof, though limited, 
is evident at the heels; especially on feet which have never been 
shod.—(Merclie.) There is especially in the inside of the foot, 
in the soft and supple parts, a certain compressibility of the 
hoof, which is often overlooked, and which is interfered with by a 
too narrow or unmethodical shoeing. 
The external dilatation of the hoof is comparatively limited, 
but on the inside of the hoof, there is in the posterior part of the 
foot* (especially in the fore feet) a movement downwards and 
outwards of the os pedis, for whether the normal elasticity of 
the hoof is necessary, either by the physical and physiological 
constitution or the arrangement of the constituent parts of the 
hoof. Quite often then, shoeing, especially if too tight, resists 
the internal pressure. Let us even admit that the dilatation of the 
heel be normal, shoeing which would prevent it would always pro¬ 
duce, at the time of rest, a pressure upon the hoof which would 
limit the compressibility of the deep soft tissues. The frog 
especially, formed of a softer horn, and placed under the plantar 
cushion, must receive this gradual pressure, which diminishes by 
degrees as the hoof becomes harder, and is reduced considerably 
as it reaches the external horny layers. 
The errors committed in shoeing, and which predispose to 
hoof bound, vary. The first is the manner in which the foot is 
