THE FRAMEWORK OF THE HORSE. 23 



the position x 3 x 3 , and in this case it will slant the 

 other way, the end c d being lower. 



Now this is just what takes place when a rider is 

 put on a horse's back in analogous positions, leaving 

 out of the question for the moment the influence of 

 the overhanging head and neck on the stability of the 

 machine. Referring back to Plate I., we see, in fact, 

 that the points a and d of the board correspond with 

 the hip and shoulder joints A and D on the one side 

 of the horse, as b and c do with the same joints on 

 the other, and these are the two points of support of 

 the back, whilst p corresponds with the fourteenth ver- 

 tebra at E ; and, still leaving the head and neck out 

 of the question, the rider placed here would sit not 

 only directly over the centre of motion, but also over the 

 centre of gravity that is to say, a central point equally 

 removed from each of its four supporting points ; * he 

 would occupy the apex or summit of a regular pyra- 

 mid, the most stable of all forms of construction. 



Let us now suppose the rider, or the weight, whatever 

 it may consist of, placed farther back towards the horse's 



* It is to be remarked that the points on which the horse's feet 

 stand seldom coincide exactly that is, lie precisely under the shoul- 

 der and hip joints respectively. The fore feet especially seldom 

 reach, even with the toes, the perpendiculars from the shoulder- 

 joints. With Eclipse they did so naturally, with tolerably well- 

 built horses moderately " set up " they will generally do so ; and if 

 the setting-up is carried beyond a certain point, they not only reach 

 but project before them, the two hind feet either following propor- 

 tionately in the same direction, or going to the rear, as may be 

 seen when the horse-dealer " stretches a horse," in order to show 

 how much ground it covers. There is a great difference, too, be- 

 tween the jointed flexible legs of a horse, and the rigid straight 

 ones represented in tig. 1. An animal always exerts a certain 

 amount of muscular action to maintain its balance even when 

 resting. 



