68 MECHANISM OF EQUINE LOCOMOTION. 



famous jumper and sprinter, leaped over a full-sized billiard-table lengthwise, 

 he was computed to have cleared a height of five feet four inches. Hence, 

 animals like the antelope and cheetah, which adopt, when going at full 

 speed, a leaping style of gallop {see p. 128), can keep it up only for a short 

 time. This fact is particularly well marked in the case of the kangaroo. For 

 the same reason, a horse can go a distance with more ease to himself at 

 a slow trot (which has no period of suspension), than at the flying trot 

 {see p. 98) or gallop {see p. 112), in both of which there is a period of 

 suspension. Not alone does the consideration of the comparative rise and 

 fall of the centre of gravity give us an idea of the relative fatigue undergone 

 during the various paces ; but it also furnishes us with a guide to judge 

 of the comparative ease with which different horses move at the same pace. 

 Consequently, we may conclude that the more " level" a horse goes, whether 

 at the fast trot, gallop, or other pace, the less will he fatigue himself : a fact 

 which proves how thoroughly reasonable is the admiration every good judge 

 has for a " level " style of movement — that is, one in which there is the least 

 possible rise and fall of the forehand at each stride. I have purposely used 

 the word "forehand" here. When noting whether the action of ahorse is 

 level or not, w'e are usually guided by the presence or absence of up-and-down 

 motion in the forehand ; for the special prominence of the head and neck 

 will more or less rivet the attention of the eyes. Besides this, the centre of 

 gravity of the horse's body is nearer his fore legs than his hind ones. 



I may mention that as soon as fast antelopes, like the Indian Black Buck 

 and South African Springbok, get tired in their bounding kind of gallop, they 

 " settle down " to one resembling that of the horse {see Figs. 90 to 105). 

 When the cheetah — ^who, as far as I can make out, gallops like the cat 

 {see Figs. 126 to 131), in a succession of leaps — becomes tired of that pace, 

 he drops into a walk or trot. 



On page 66 I have alluded to the effects of the lateral displacement 

 of the centre of gravity in causing fatigue. 



The pace which is the speediest, is also the most fatiguing ; for, as in fast 

 paces, tlie centre of gravity will be carried further beyond its base of support 

 than at slow ones, a greater muscular effort will be required in them to form 

 a new base of support. We may see this if we compare, one with another, 

 Figs. 42, 45, 55, 79, and loi. 



Action of the Head and Neck in Locomotion. — During 

 movement, the head and neck act as a balancing pole in changing the 

 position of the centre of gravity from one side to the other, and in raising or 



