SECTION V.-EQUINE LOCOMOTION 



The paces of the horse cannot well be understood without reference to 

 the means by which locomotion is brought about. 



In the anatomical portion of this work frequent reference will be found 

 to the origin and insertion of muscles, and the attachments of tendons and 

 ligaments. Attention is called to the fixed points upon which muscles act 

 by the shortening of their body or " belly". The stimulus of the will or 

 other agents put in action a force which causes a contraction of muscular 

 fibre, resulting in approximation of the fixed points of origin and insertion. 



A familiar example of this action is seen when the human biceps, by its 

 bellying or contraction, changes the contour of the limb and brings the 

 hand to the point of the shoulder. 



The horse may be viewed as a living mechanism, a series of pulleys and 

 levers attached to bones, and having the ground for a fulcrum. 



The comparison is not, however, so complete as some Continental writers 

 have striven to prove. Marey says : " The comparison between ordinary 

 machines and animated motive powers will not have been made in vain 

 if it has shown that strict relations exist between the form of the organs 

 and the character of their functions; that this correspondence is regulated 

 by the ordinary laws of mechanics; so that when we see the muscular and 

 bony structure of an animal we may deduce from their form all the char- 

 acters and functions they possess". 



THE HORSE STANDING 



Given a sound, well-proportioned horse standing to " attention ", or 

 " collectedly " as masters of equitation are wont to term it, with head up 

 and ears forward, the face will have a profile whose angle to the ground 

 is about 45 degrees, and the weight will be equally distributed among 

 the four supports (limbs). As a matter of observation, horses seldom adopt 

 this exact position, rather choosing to advance one foot slightly in front 

 of its fellow, despite the training which they may have undergone in " dress- 

 ing" in a troop of horses. 



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