20 Animal Life 
In a horse, the bones of the upper segments of the limbs are 
set very obliquely to one another; and as those of the lower segments 
are much more elongated (both actually and proportionately) than in 
man, the running and leaping powers are greatly increased. Both 
in walking (Fig. 6) and in trotting (Fig. 7) the diagonal movement 
of the lmbs occurs, although it is only in the latter mode of loco- ) 
motion that one fore-limb moves synchronously with the hind-lmb Fig, 12. 
of the opposite side. Supposing a horse starts his walk by raising 
first the left fore-foot (and it is a remarkable fact that most domesticated horses, perhaps 
as the result of trainmg, show a marked tendency to ‘lead with the left”), the next 
to be advanced will be the might or diagonal hind-foot; the latter being followed in 
turn by the right fore-foot, andl this again by its diagonal, namely, the ‘left hind-foot. 
In slow wailing (Fig. 7) the horse has always three feet on the ground; but when 
moving at a more rapid walk (Fig. 6) there are short intervals during which two feet are 
off the ground simultaneously, although these intervals are so short that the fact cannot 
be detected by the naked eye. 
Owing to the diagonal and alternate movements of the limbs in walking, a more — 
or less nearly horizontal roll is communicated to the whole body of the horse. ‘This 
roll is, however, still more conspicuous in smaller animals, such as dogs and cats, in 
which a continuous oblique wave of motion seems to traverse their bodies as they 
advance at a walk or a slow trot. Here it may be mentioned that all, or nearly all, 
domesticated dogs, when walking or trotting in a given direction, invariably hold the 
body more or less obliquely to the line of progress; this oblique position being most 
noticeable in the smaller short-tailed breeds, such as fox-terriers (Fig. 12), some of which 
advance in an almost crab-like fashion. On the other hand, when at speed, the larger 
dogs at any vate, such as foxhounds and greyhounds, apparently have the axis of the body 
coincident with the line of. progress. All wild members of the growp, such as foxes, 
jackals and wolves, always carry the body perfectly straight (Fig. 13); and it would be 
very interesting to know the reason why the domesticated breeds have departed from this 
practice. The idea that the oblique position of the body is connected with the curling of 
the tail, characteristic of so many domesticated breeds, naturally suggests itself; but even if 
this be true, it does not much assist matters, so far as a reason is concerned. 
In trotting, when the legs move diagonally in pairs, the undulations induced in the 
body by the movement are mainly in a vertical, in place of a horizontal, plane. In 
trotting, each leg is moved somewhat oftener in a given length of time, the ratio 
being as six to five. The advantage gained in speed by moving the legs diagonally in 
paws instead of consecutively is due to the fact that in trotting (Figs. 8 and 9) each foot 
is on the ground for a short interval and in the air for a long one; just the reverse 
of this state of things taking place in walking (Fig. 16). 
From this diagonal motion of the limbs, it follows’that when animals like horses, 
cattle, deer, pigs, dogs, etc., come to a standstill (Fig. 5) 
they often have the two feet of one side comparatively 
Lf close together, while those of the opposite side are as 
: ss far apart as possible. That is to say, the two feet of 
om oy ee one side—the right, for instance—will be directly under 
0 ‘ ae ig iy the body ; while those of the other side—the left, in this 
Cristy le Mal instance—will project beyond its two extremities. Such 
‘ 3 moves the two limbs of the same side simultaneously. 
Omitting mention of the canter, the next important 
a position is impossible in the case of an animal which 
Vig. 13. natural pace of the horse is the gallop, in regard to 
