I94 THE SEAT. 



cerned, should be taken with the view of preventing the rider 

 from being thrown forward on sudden provocation (Fig. 181). 

 As any pull on the reins given by the horse is transmitted 

 through the arms to the shoulder joints, and as these joints 

 are at a comparatively long distance from the centre of 

 gravity of the rider's body ; the power which he obtains from 

 the reins in preventing his body from going in a backward 

 direction, acts to great mechanical advantage. In endeavour- 



Fig. 181. Stopping short. 



ing to save himself from being moved unduly forward out 

 of the saddle, it is necessary for the rider to have a fairly 

 broad base of support, and to have the means of prevent- 

 ing his centre of gravity from being carried beyond it. The 

 base of support in question is formed by the thighs and lower 

 bones of the pelvis. Hence the thighs should be kept in a 

 sloped position, and not perpendicular. The degree of their 

 slope must however be compatible with ability on the part of 

 the rider to apply the lower portion of his legs to the animal's 

 sides, so that he may be able to direct, control, and stimulate 



