REVIEW. 
33 
Chap. II.—On Locomotion. 
Our own country writers “ on the foot ” have been too much 
in the habit of restricting their observations to the foot itself, 
treating on it as though it were an insulated organ; whereas 
it must be obvious, at least so far as its locomotion is concerned, 
that it cannot be regarded, with propriety, in any other light 
than as part and parcel of the locomotive apparatus of the entire 
limb to which it belongs; and so far will there, in this respect* 
exist differences between the fore and hind foot. M. Bouley 
has, judiciously, viewed the subject on this comprehensive scale. 
He commences the present chapter by quoting from Bracy 
Clark, that in the horse “ is accomplished one of the most dif¬ 
ficult problems in mechanics, viz., the moving of a large and 
heavy body with an extraordinary degree of velocity.” Through 
what combinations of structure so surprising a result is brought 
about, it will be for us, says M. Bouley, to inquire. The 
following extracts—of necessity brief, to accommodate them 
to our pages—will exhibit the scientific manner in which this 
inquiry has been conducted :— 
“ The horse, one of the most bulky and ponderous animals of 
creation, is likewise, at the same time, one endowed with the 
greatest freedom of action and rapidity of movement, and that 
possesses the power of instantaneous translation of his bulky 
body in the highest degree ; a felicitous combination of contrary 
faculties to which the study of the machine furnishes the key. 
“ The limbs, the essential parts in this function, are made up 
of columns of support and of organs of impulsion. 
“What is remarkable in the disposition of the shafts composing 
these columns is their, in general, angular disposition in relation 
to each other. Such arrangement is, doubtless, unfavourable 
for solidity, seeing that the force and resistance of a column 
must depend upon the perpendicular superposition of its con¬ 
stituent layers ; but, on the other hand, it conduces to the action 
and power of the muscles; whilst, by an ingenious antagonism 
of muscles and tendons, the osseous angles acquire, in the given 
time, a sufficiency of stiffness to resist impressions having a 
tendency to close them, from which they relax onty at such 
times as re-action is called for. Thus, by a mechanism and dis¬ 
position so admirable, is insured two opposite properties, rigidity 
and flexibility, through the agency of which the limb answers the 
double purpose of a column of support and an organ of impulsion 
VOL. XXV. F 
