THE HORSE’S FOOT. 
385 
beneath, and so incurable cracks are the result. A double wall 
or false quittor have often also been observed. Thus deformed, 
the foot is always subject to lameness, even if the crack is cured. 
Contraction or atrophy of the frog have been observed with quar¬ 
ter-crack. 
IV. Progress , Duration , Termination .—Ordinarily cracks 
once existing become worse. From being superficial and imper¬ 
fect they become deep and complete as a natural result of the 
ordinary motions of the foot. If rest and some hygienic atten¬ 
tion can be given, they may recover spontaneously, and disap¬ 
pear by the natural downward growth of the hoof. This fortu¬ 
nate termination, however, is principally obtained when the crack 
is due to accidental causes, without deformity of the foot. 
Y. Prognosis .—Simple cracks, superficial and incomplete, 
especially arising from the plantar border, almost always recover 
under rational treatment, which has for its principal aim the pre¬ 
vention of increase in the size of the fissure. Cracks starting: 
from the coronary band are always of a more serious nature, with 
a tendency to increase easily. Still they are no longer to be con¬ 
sidered incurable. Cracks in which the borders are much sepa¬ 
rated by the motion of walking ; those which are oblique; those 
whose edges are incurvated inwards ; those where a portion of 
the wall is loose; those which bleed, and those where there is a 
continued irritation of the sub-horny tissues, are the most serious, 
so much so that they may require quite serious surgical interfer- 
fence, and after all baffie the best skill of the operator. 
VI. Etiology .—The causes of cracks vary greatly, and are 
often multiple in a single case. Seldom the result of accident, 
they are most commonly the combined effect of both a predispos¬ 
ing and an extraueous cause. A frequent one among others is 
the relative dryness of the hoof, which then become excessively 
brittle. We have seen the conditions in which the hoof loses 
its natural flexibility, and shall here only state that alternate 
changes from dampness to dryness have as much influence as the 
dryness alone. Cracks are more frequent in animals working 
along damp than in those pulling in dry and stony roads. They 
are common in animals which, after being kept in pastures, are 
