650 ON THE SENSE OF TOUCH IN THE HORSE’S FOOT. 
the intensity of the percussion. So that the foot, at the extremity 
of the column of bones, is rendered a sort of block or inert body, 
without any dependence on the sensitive system, which the animal 
projects and strikes against any obstacle that happens to stand up 
from the ground, without forseeing what may happen from it ; 
without, indeed, feeling what the obstruction is ; and, such under 
certain conditions, may be the consequences of these unreckoned 
upon and miscalculated percussions of the foot against the ground, 
that it is by no means uncommon to see, as the effect of hurried and 
protracted journeys, neurotomized horses cast their hoofs, which 
have become detached through softening and gangrene of the 
living parts underneath. 
Another consequence of the operation of neurotomy is the in- 
certitude occasioned to the equilibrium of the machine, especially 
in rapid movements. 
From the foregoing rapid sketch, it appears to us that the sensi- 
bility wherewith the digital extremities of the horse are endowed 
in so eminent a degree, constitutes the fundamental condition of his 
firmness of attitude and safety of movement, which remains so 
secure, notwithstanding the instability of his equilibrium. The 
pathologist will also know well what value to set upon it in his 
treatment of the important diseases to which the interior of the foot 
is so obnoxious*. 
Recueil de Med. Vet., June, 1850. 
* On the same subject Mr. Percivall has written to the following effect : — 
“ There can be no doubt but what the horse feels the ground upon which he 
is treading, and that he regulates his action in consonance with such feeling, 
so as to render his step the least jarring and fatiguing to himself, and there- 
fore the easiest and pleasantest to his rider. The tread of the hoof creates 
a certain impression — depending on the nature of the ground trodden upon, 
and the force and manner with which the tread is made — on the nerves (of 
sensation) of the foot ; which nerves being associated above the knee, in 
their course to the sensorium, with motor nervous fibres, the motions excited 
by the latter will necessarily be more or less influenced, through the will, by 
the impressions they receive from the former. Such impressions being, 
in the neurotomized subject, so far as regards the feeling of the foot, alto- 
gether wanting, a bold fearless projection of the limb in action will be the 
consequence, followed by a putting down of the hoof flat upon the ground as 
though it were a block, creating a sensation alike unpleasant both to horse 
and rider. These combined alterations in action and mode of setting down 
the feet it is which give rise to the peculiarity in the gait of the neurotomized 
horse — consisting in lack of elasticity and consequent jarring movement — by 
which he is ever, when both fore feet have been operated on, distinguished by 
a rider experienced in such matters from other horses, as well as characterised 
in action and gait from what he formerly was himself .” — On Lameness in the 
Horse, pp. 190 and 191. 
