530 



ON DRAUGHT. 



It perhaps may have been found difficult or troublesome to watch the 

 movement of a horse's legs ; but a very little practice will enable anybody 

 to verify what we are about to state : by keeping near the side of a horse 

 that is walking, it will be easily seen that, immediately after the raisino- of 

 either of the hmd-legs from the ground, the fore-leg of the corresponding 

 side IS also raised, so that the latter leaves the ground just before the 

 former touches it. If the fore-legs be then watched, it will be seen that 

 immediately after the movement of either of these, the hind-leg upon 

 the opposite side is put in action, so that the order of succession appears 

 to be in walking, as numbered in fig. 3. 



If the horse be now examined from a short distance, it will be seen that 

 when he is walking freely, the successive movements of the leo-s are at 

 equal intervals of time, and that the muscular force of one limb only is 

 brought into action at the same moment. But if a horse which is drag- 

 ging a load with some considerable exertion be watched, it w411 be seen 

 that he then acts longer upon his legs, and allows a less interval of time 

 for raising and advancing them ; and, at the same time, the reo-ularity of 

 the movement is generally destroyed ; the limbs on the same side generally 

 being moved more simultaneously, or at nearer intervals of time, than 

 those at the opposite corners : thus, the muscular forces of two limbs are 

 always acting together ; the movement of the whole body is less continued 

 and uniform than in the former case, but each impulse is more powerful 

 and a resistance, which would be too great for the muscles of one leo- is 

 overcome by the united exertion of two. We shall point out, hereafter 

 the necessity of attending to this in the application of this power to drauo-ht. 

 In trotting, the action is of course quicker, and a less resistance will, as 

 might be expected, cause the horse to move his legs at two intervals in- 

 stead of at four equal intervals of time : indeed, a horse accustomed to 

 go in harness generally acquires the habit of that action. There is this 

 striking difference between trotting and walking : in walkino-, we have 

 seen that the interval between the movement of the legs on the same side 

 was less than the other interval of time : in trotting, on the contrary, the 

 legs situated diagonally, or at opposite corners, move almost simulta- 

 neously. Owing to the velocity and the moinentum which the body 

 acquires in consequence of that velocity, in trotting fast, the successive 

 impulses are less distinctly perceptible, and the movement more continued 

 and uniform than in a slow trot, or in walking. 



In galloping, the movement is totally different : the fore-legs are thrown 

 forward nearly simultaneously, and the hind-legs brought up quickly, and 

 nearly together ; it is, in fact, a succession of leaps, by far the greatest 



