REGULA TION OF THE CENTRE OF GRA V/TV. 85 



and neck are the fixed point ; the fore Hmb, the movable one. 

 As long, therefore, as the speed of any particular pace remains 

 uniform, the length of the neck (measured roughly from 

 withers to top of head) should continue unchanged. Con- 

 sequently, when riding or driving, if we desire the horse to 

 maintain a uniform rate of speed, we should keep a uniform 

 tension on the reins (note, for instance, the fixed position of 

 the hands of a capable lad from a racing stable when he is 

 riding a steady training gallop), and should not "give and 

 take" with them. If the speed be increased, the hands, 

 supposing their hold on the reins remains unaltered, should 

 be advanced, as may be required ; if it be decreased, they 

 should be drawn back. Thus, any alteration by the rider, of 

 tension on the reins which might impede the legitimate 

 movements of the neck, is avoided. As the joint which the 

 head makes with the a^/as (first vertebra of the neck) is 

 situated some distance below the top of the head, it follows 

 that if the muzzle be unduly stretched out, the occipital crest 

 (top of the head) will be brought back, and the tension of 

 the ligament of the neck lessened, with consequent decrease 

 of power to the muscles which are attached to this ligament. 

 The muscle which is attached to the humerus and top of 

 the head, also would w^ork to disadvantage if the muzzle were 

 stretched out to a greater extent than would bring the line 

 of the face to a right angle with the direction of this muscle, 

 which forms the upper border of the jugular groove. Even in 

 the fast gallop {mde Figs. 90 to 105), the horse rarely carries 

 his head at a less angle than 45*^ to the ground. 



(3) To regulate the position of the Ceyitre of Gravity. — 

 The more the head is advanced to the front, the more 

 unstable will be the equilibrium, and the greater will be the 



