74 



MECHANISM OF EQUINE LOCOMOTION. 



should bear in mind that the toe (except in the treatment of some forms 

 of disease) should always be kept low, and that shoes should be no 

 thicker at the toes than what would be sufficient to enable them to stand 

 " wear." Special allusion to this subject has been made in Veterinary 

 Notes for Horse-Owners. 



Mechanism of the Hock Joint. — Figs. 46, 47, and 48 show the 

 three actions of this joint as a lever. 



Fig. 46. —1st Order 



Fig. 48. — 3rd Order. 



Fig. 47. — 2nd Order. 

 Levers ov the Hock. 



Besides flexion and extension, this joint has an outward motion, due 

 to the outward and forward direction of the pulley formed by the 

 astragalus. 



We find, contrary to what we might have expected from an inspection 

 of this bone, that this oblique play of the hock joint does not affect the 

 direction in which the hind foot is carried ; its object being, as explained 

 by H. Bouley, to allow the stifle to clear the abdomen, when the hind 

 foot is brought forward. 



