LECTURES ON HORSES. 
303 
have the limbs to support the body, but they have to carry it 
from place to place, and at the same time to move themselves 
under their burthen with more or less velocity. In a three-legged 
stool, or in a four-legged form or table, the legs are placed at the 
circumferent parts or projecting angles, as far apart as possible 
from each other, the objects being to extend the base or standing, 
and at the same time avoid the risk of the legs coming at any 
time, from weight imposed too near the edge, within the centre of 
gravity, and thereby proving incapable of saving the stool or table 
from upsetting. In these cases stability and strength is all that is 
required ; but in the instance of the vital machine, not only are 
strength and stability needed, but facility of motion likewise; 
and extension of the sphere of the base or standing which would 
have better insured the one would have added difficulties or im- 
pediments in the way of the other. 
Nature has placed her props of support at the extreme points 
or salient angles of the animal machine, and longitudinally has 
extended the sphere of the base, but laterally has narrowed the 
body, and approximated the limbs, in order that the superincum- 
bent burthen might as little as possible incommode them in their 
motions forwards and backwards, during progression. 
When speaking of the chest, I observed, that the wider that 
cavity was made, the farther the two fore limbs must necessarily 
be thrown apart. This cannot fail to have an effect both on the 
standing and on the progression of the animal. A broad-chested 
horse — a cart or dray horse — stands more securely than a narrow- 
chested horse : his base of standing is wider, his props of support 
being farther removed from the centre of gravity. But, when the 
machine comes to be moved, the limbs, thus widely separated, will 
not operate with the same effect as others more directly under the 
centre of gravity — will not carry their load with the same advan- 
tage, nor will they act so straight-forwardly or so harmoniously 
together. The racer and the cart-horse, the greyhound and the 
bull-dog, and, among bipeds, the turkey and the goose, as I before 
stated, strikingly illustrate this point of structure in their make 
and in the gait or action arising out of it : to mark this difference 
we have but to compare the straight stealing-onward step of the 
racer with the round and short step of the dray-horse ; the steady 
smooth canter of the greyhound with the rolling gait of the bull- 
dog; the pointed parade-like walk of the pea-fowl or the turkey 
with the waddle of the duck or goose. Nay ; I might adduce even 
the human body — the woman with her broad hips, the man with 
his straight or narrow ones — to shew what a difference in the gait 
results from the limbs being thrown apart at the axes of their 
motions. 
