stones, and the latter, with the increased concussion they will entail on
the limb, are active factors in the troubles with which we are about to
deal. Upon these unyielding surfaces the horse is called to carry slowly or
rapidly, as the case may be, not only his own weight, but, in addition, is
asked to labour at the hauling of heavy loads. The effects of concussion
and heavy traction combined are bound primarily to find the feet, and such
diseases as side-bones, ringbones, corns, and sand-cracks commence to make
their appearance.

Again, as opposed to the comparative healthiness of the surroundings when
at grass, consideration must be given to the chemical changes the foot is
frequently subjected to when the animal is housed.

Only too often the bedding the animal has to stand upon for several hours
of the twenty-four can only be fitly described as 'filthy in the extreme.'
The ammoniacal exhalations from these collected body-discharges must, and
do, have a prejudicial effect upon the nature of the horn, and, though slow
in its progress, mischief is bound sooner or later to occur in the shape of
a weakened and discharging frog, with its concomitant of contracted heels.
Lucky it is in such a case if canker does not follow on.

Observers, too, have chronicled the occurrence in horse's feet of disease
resulting from the use of moss litter. Tenderness in the foot is first
noticeable, which tenderness is afterwards followed by a peculiar softening
of the horn of the sole and the frog. What should be a dense, fairly
resilient substance is transformed into a material affording a yielding
sensation to the fingers not unlike that imparted by a soft indiarubber,
and as easily sliced as cheese-rind.

Lastly, though the foot is extremely liable to suffer from the effects