56 MATERIALS FOR A MEMOIR ON 



With these facts before us and the photographs examined, it 

 will be seen that in the horse (series 576), the figure of the animal 

 being seen foreshortened from behind at ninety degrees, the right 

 hind foot is barely off the ground, and has not lost the position 

 of the ankle when seen in backward strain. The produced axis 

 of the leg will intersect the axis of the metatarsus at the position 

 which corresponds to the production of the axis of the astragalus- 

 pulley in the skeleton. 



In the ox (series 671, Fig. 12) the rear view of the left hind 

 leg exhibits a totally different inclination. The foot is on the 

 ground, but is about to leave it, and the produced line is much 

 nearer the vertical. In the hog, as shown in series 674, Fig. 4, 

 the axis of the astragalus as far as can be ascertained is also that 

 of the leg. 



Training and Age as Factors of Disturbance. 



The difficulty in studying the actions of the domesticated ani- 

 mals, especially of the horse, is owing in the main to the fact 

 that the training to which the animal has been subjected modifies 

 his movement. The draught-horse comes down on the tip of 

 the foot instead of the heel, as is the case with other quadrupeds. 

 In like manner the movements of the well-bred horse are influ- 

 enced by the skill of the driver. In the gallop (series 624) it is 

 evident that the rider is at fault in the management of the horse 

 and disturbs his action. 



The trot and the fast gaits, such as the run and the act of the 

 leap as taken by the horse trained for the circus, are unnatural, 

 and belong to the class of the acts of the acrobat and the contor- 

 tionist as seen in the human movements. (See p. 6Q.) 



The fact that the horse in racing can place each of the feet in 

 succession in the same spot is in this relation unessential, and need 

 not militate against any conclusion drawn from slower and more 

 natural movements. The same remark is applicable to the fact 

 that the fast horse, even in the walk, will place the hind foot on 

 the ground in advance of the fore foot. 



The age of an animal will modify the movements. An old 

 horse, as already seen, will place the tip of the hoof to the ground 

 instead of the heel. In the same class the hind foot is advanced 

 to a less degree than the young. In the colt, on the other hand, 



