218 ON PROGRESSION. 



what is required of him, he feels in constant 



apprehension of faUing. 



As the horse recovers his center In a straiijht 

 line of progression, by advancing one leg be- 

 yond the other, so will he recover his center in 

 a lateral progression, by crossing one leg beyond 

 the other. Thus, if the horse moves sideways 

 to the right, he crosses over his left fore and 

 liind legs beyond the right fore and hind legs at 

 the same period, and thereby recovers his per- 

 pendicular position. In going tothe left he 

 crosses with his right legs. But he would be un- 

 able to cross his legs if his body moved perfectly 

 laterally, he is therefore obliged to advance one 

 shoulder beyond the other by moving obliquely. 



When the horse has been accustomed to 

 this pace for some time, it will be necessary that 

 he should be taught to perform it with a rider 

 on his back. For which purpose, if he is re- 

 quired 



