PRACTICAL HORSESHOEIXG. 73 



of the foot in health and its protection from injury. The hoof 

 incloses the coffin-bone, which is the terminal bone of the leg. 

 To this bone are attached the principal tendons that bend 

 and thrust the foot forward, and to it also grow the tough but 

 tender, leafy tissues which dovetail into horny ridges on the 

 wall ; these attachments being technically called the sensitive 

 and insensitive laminee. These leafy tissues working together, 

 carry the stress of weight with an elastic movement, their vari- 

 ation, under pressure and without, being found to be about one 

 quarter of an inch. The result is a wonderful elastic spring be- 

 tween the end of the leg and the external hoof, and tliis with 

 the springy action of the coronary and frog cushions and lateral 

 cartilages, acting together with the expansion of the arched 

 bars — all being compressible under pressure — is the wise provi- 

 sion of nature to ward off and minimize the concussion on a 

 horse's foot in motion. 



The Center of Gravity. — Having reached this point, let 

 us observe the going as well as the external and internal struct- 

 ure of a horse's foot. The horse then who draws presses first 

 on the toe, then successively on the sides to ease the toe, then 

 upon the heel, from which it immediately rises again. Trot- 

 ting and running horses press the toe relatively lighter, landing 

 first upon the heel, but in either case the effort of the weight 

 of the horses fixes the real point of support neither upon the 

 heel or toe, but on the middle or ball of the foot — between 

 both, where is located the center of gravity, which is easy to 

 demonstrate anatomically: thus, the cannon-bone presses on the 

 head of the upper pastern, this on the lower pastern, this again 

 on the navicular and coffin-bones, the center from where it is 

 projected upon the ground bearings of the hoof without. In a 

 sound and healthy organization, the succession of rapid move- 

 ments of the living animal, adducts or shifts the center of grav- 

 ity toward and through the median line or center of the heads 



