they exert on
the sole corns result, and the animal is lamed.

_Causes_.--In the main this defect is hereditary. It is seen commonly in
connection with flat-foot, and where the horn of the wall is thin and
shelly.

_Treatment_.--In the case of weak or 'turned in' heels no suitable bearing
is offered for the shoe in the posterior half of the foot. Any attempt to
induce the heels to bear weight is immediately followed by their bending
in. It follows from this that the best shoe to be used here is one in which
the bearing is confined to the anterior half of the wall, the heels being
relieved by being sufficiently pared. As might be expected, this bearing on
the anterior half only of the foot is insufficient; pressure must be given
the frog. This latter end is best gained by a bar shoe (Fig. 68). With it
the anterior portions of the wall, the whole of the bars, and the whole
of the frog may be in contact, and the heels only so pared as to take no
bearing at all. A few such shoeings sees the defect remedied. In every
instance paring of the sole should be discouraged, as it serves but to
increase the deformity.

B. CONTRACTED FOOT.

_(a)_ GENERAL CONTRACTION--CONTRACTED HEELS.

_Definition_. By the term contracted foot, otherwise known as hoof-bound,
is indicated a condition in which the foot, more especially the posterior
half of it, is, or becomes, narrower from side to side than is normal.

It must be borne in mind, however, that certain breeds of horses have
normally a foot which nearer approaches the oval than the circular in form,
and that a narrow foot is not necessarily a contracted foot.

The contraction may be bilateral when affecting both heels of the same foot
and extending to the quarters, or unilateral when the inside or outside
heel only is affected.

In some cases contraction is confined to one foot, while in others it may
be noticed equally bad in both. It is a matter of common knowledge that
contraction is usually seen in the fore-feet, while the hind seldom or
never suffer from it, a fact which, to our minds, seems difficult of
adequate explanation. Zundel explains this by stating that contraction is
principally _observed_ in the fore-feet, by reason of the fact that when
lameness arises from it alteration in action will more readily be detected
in front than behind. Percival, on the other hand, suggests that the
greater expansive powers of the hind-foot, by reason of the impetus of its
action, i