OBSERVATIONS ON SOUNDNESS. 
453 
upon the hard pavement, rather than upon smooth and 
well-cared for macadamized roads, although we do now and 
then meet with high steppers and good goers who constantly 
hammer their feet as they travel along the road. At the same 
time it must be admitted that we do not hear so much of navi¬ 
cular disease now as we formerly did; whether it is because we 
are more conversant with other affections of the feet, or 
whether it is in consequence of the feet being more carefully 
and properly shod, I am not prepared to state, but I am inclined 
to the opinion that as our knowledge of the foot increases so 
will the existence of navicular disease be considered less fre¬ 
quent in our diagnosis. Nature has made ample provision in 
the foot to prevent the inroads of disease from wear and tear 
consequent upon exertion. It is a question, however, whether 
that provision is sufficient for the present requirements of the 
animal. We must bear in mind that we are to consider the 
foot as intended by the Allwise to be sufficiently perfect in all 
its parts to serve the purposes in an artificial state as well 
as during a state of nature. 
The inferior and lateral cartilages are doing good service 
in their several departments; the movements of the former 
are trivial when compared to the latter. The lateral car¬ 
tilages are called upon to do a vast amount of work, indeed 
every motion of the foot is in some way or other exciting an 
influence upon these cartilages, and this will in some measure 
explain the reason why a transformation of their structure is so 
frequently met with in our examinations. When we reflect 
upon the functions which the lateral cartilages have to perform, 
together with their peculiar conformation, we no longer 
wonder that they are so liable to disease. The bond of union 
existing between the horny covering and the sensitive parts 
of the foot demand our especial attention, inasmuch as we 
have of late been led to understand that the lamellated struc¬ 
tures are not so susceptible of injury as we were wont to 
believe they were. Take, for example, thefive hundred dovetailed 
connections. If a mechanic were shown these structures and 
adaptations, he would, I am sure, exclaim that there must of 
necessity be great force exerted upon these different parts in 
sustaining, not only the weight superimposed upon them, but 
the weight produced by rapidity of motion, and that upon 
all kinds of roads, not only hard ones, but uneven also. These 
several things, I have no hesitation in asserting, must cause 
derangements of the parts during a long course of work. Too 
much cannot be said of this part of the foot in my humble 
opinion. The connection between the os pedis and the sole 
has of late brought out some remarks from the pen of Mr. 
