ANATOMY AND PHYSIOLOGY OF THE HORSE’S FOOT. 153 
spond with the upper face ; its most depressed portion — after 
all the loose flaky horn has been removed for a more careful 
examination — is at the point of the frog. From here it in- 
clines towards the wall, and when yet some distance from 
it becomes plane, until it finally joins it. In the unpared 
foot exposed to wear, this plane surface comes more or less in 
contact with the ground along with the wall. In the ordi- 
nary pared foot the whole surface is usually made concave, 
thin, and smooth; hut in the unshod state, or when this 
mutilation has not been allowed, it is thick, and covered 
with rough flakes of horn in process of exfoliation, which 
cause it to look more flat. 
The outer or circular border of the sole represents its width, 
and is more or less thick, as the foot is left intact and exposed 
to wear or pared. It is united to the wall by the dovetailing 
of the horny laminee into the margin of the sole, and 
so strong and perfect is this union that many months’ steep- 
ing in water is necessary to disunite them. The junction 
between the circumference of the sole and the lower extremity 
of the wall is marked by a zone, as already noted, which 
differs in colour and consistency from the other parts. The 
inner or irregularly triangular border is much thinner than 
the outer, and, like it, is also dovetailed into the horny laminae 
on the inflections of the wall or “ bars.” It is likewise 
united to the sides and point of the frog, in front of the ter- 
mination of the bars. 
The sole is divided into regions which correspond to and 
receive the same designations as the wall. 
The thickness of the sole is not the same throughout. In 
the hoof pared according to the barbarous principles which 
are euphemistically termed £f improved” by those who prac- 
tise them, it may be found reduced to the thinnest pellicle of 
horn, through which light easily passes. But in a normal 
condition it is ordinarily as thick at its outer circumference 
as the wall ; though, of course, if the hoof has been exposed 
to unusualattrition.it will lose much of its substance. From 
its outer border it continues for a little distance undiminished, 
and then gradually becomes thin as far as the centre, where 
it is most attenuated. Its thickness is, as a rule, limited, 
because of the natural exfoliation that take places whenever 
a certain amount of growth is attained. 
The hardness or consistency of the sole is, as with the wall, 
in direct relation to its distance from the living tissues ; in 
its proximity to these it is soft and somewhat elastic, and as 
it recedes from them it becomes solid, resisting, and inelastic. 
Towards its circumference, therefore, it offers its highest 
