THE CON CAVE-SEATED SHOE. 
395 
when the foot of the animal is placed on the ground, and is 
unable to bear constant or even temporary pressure for any 
length of time ; and if it bears upon the shoe, the sensible 
sole between the coffin-bone and horny external sole would 
be so much bruised as to occasion lameness, and if long 
continued it would be of a very serious character. Work¬ 
ing horses too early has a strong tendency to flatten the 
natural concavity of the sole, and may induce a disposition 
to continued descent. This bevelling of the concave shoe 
prevents the possibility of injury or sinking of the sole. If 
the feet are pumiced, the shoe must have an extra degree of 
bevelling to protect them. 
When shoes are flat, gravel and dirt constantly insinuate 
themselves and lodge there, and are certain upon a journey 
to bruise and injure the foot; but in bevelled shoes, it is 
hardly possible for either to remain between the sole and 
foot, as they would naturally be shaken out every time the 
foot comes in contact with the ground. 
Another advantage in this shoe is that the web is of that 
proper thickness, that when the crust is properly pared the 
prominent part of the frog will lie immediately within and 
above its ground surface, permitting the frog to rest suffici¬ 
ently on the ground, so as to act as a wedge, and produce a 
tendency to expansion in the quarters ; while at the same 
time it is protected from 'the injury it would sustain if it 
reached the ground with the full and first shock of the 
weight. In the common shoe the ground surface is a little 
convex, and its inward rim first comes in contact with the 
ground; so that the weight, instead of resting fairly on the 
crust, is sustained by the clenches and nails, which cannot 
fail to be prejudicial to the crust, and must often tear and 
splinter it. 
The nail-holes must be situated as near the outer edge of 
