480 



THE EXTERIOR OF THE HORSE. 



2rl. Graphic Method. — It is to M. Marey, the learned professor of the 

 College de France, that the merits of the greatest progress realized in this new 

 direction must revert. In applying his method, called the graphic, to the 

 study of the locomotion of the horse, he has determined in an almost definite 

 manner most of the principles previously doubtful.' 



Fig. 173.— Two drums with a lever and tubing to carry the compressed air. (Marey.) 



Process -with Compressed Air. — Let us suppose two drums, A and B 

 (Fig. 173), each one formed of a metallic case closed above by an India-rubber 



Fig. 174. 



membrane. Upon this membrane is fixed an articulated lever, L, capable of 



executing to-and-fro vertical movements. 



1 Marey, La machine animale, p. 146, et suiv. 



