is being now exerted by the right hind foot, testing heel or hock joint again. The 

 left foot is being brought forward. But without another view taken from above 

 you will not appreciate the full beauty of this mechanism. Fig. 3. 



When you get above the horse and photograph him, from the seat of the 

 driver, you will observe that the back-bone is thrown into an S-shaped curve, 

 and that the hip on the right side is depressed; you see the significance of this 

 curve ; it is in order to bring the head of the thigh bone, which you will remem- 

 ber is exerting the thrust, as near as possible to the centre axis of the body. 

 Since the thigh is brought very nearly into the direct fore and aft line with the 

 back-bone, the thrust is transmitted through the back-bone directly to the collar. 

 When the horse takes the next step, the right side of the pelvis will be raised, the 

 left will be lowered; and the head of this thigh will swing around. The back- 

 bone curve will go in the opposite direction, and the thrust will again be ex- 

 erted as near as possible along the middle line of the axis — a perfect illustration 

 of the mechanism of the draft-horse. Fig. 4. 



In the race horse, we have illustrated the necessity of perfection of joint 

 mechanism, because in galloping the body is constantly supported in turn on one 

 foot, there being only a short period of suspension in which all four feet are 

 off the ground. In the periods in which each foot in turn is on the ground 

 there is naturally a great strain. Keep in mind the fact that this foot has 

 evolved from one finger, corresponding to your central finger, and you will see 

 what the process of evolution has done, whereby that finger has become adapted 

 to sustaining the entire weight and forward thrust of this rapidly moving and 

 heavy animal. 



In the act of jumping we have a very great strain brought very frequently, 

 especially in landing, upon the fore feet. This is a fact, which is clearly illus- 

 trated in the next photograph of one of Trumbull Carey's horses. The horse is 

 coming down on the two fore feet, therefore coming upon the joints of what 

 were the two middle fingers of the hand. Fig. 8. 



Here we have an illustration of these feet. If you were to jump to the 

 ground the accident that would most likely happen, if any, would be a slight 

 lateral dislocation or sprain. This is provided against in the horse by a series 

 of tongue and groove joints, two of which are found in the fingers; the third 

 at the elbows, and by the springy universal joint at the shoulder. In other 

 words, nature has taken every provision possible against lateral dislocation or 

 the spraining of the elongated finger; and step by step in the evolution of the 

 horse we can trace the evolution of the three tongue and groove joints in each 

 limb ; they become sharper and sharper as time goes on. Fig. 5. 



In the extraordinary jumping of Heatherbloom, we have illustrated two 

 principles; first, the power which has been attained in that animal, of getting 

 over very high obstacles — eight feet two inches I believe — and we shall refer 

 later to the fact that in the jumping horse we have a combination of two original 

 ancestral strains of horses, one contributing the element of speed and the other 

 contributing the element of lifting power. Fig. 9. 



In a rearing horse we often see the entire weight of a very heavy animal, 

 plus a rider, sustained on a single hind foot — with a great tendency therefore to 



