SYNTHESIS OF MOVEMENT 309 



on another of the same size, and the hind portions of 

 the images which had been cut away were gummed 

 each in its proper position upon the lower strip. When 

 this was done, the two strips taken together presented 

 the appearance of the original slip, namely, the suc- 

 cessive attitudes of an ambling horse during the 

 performance of one stride. If the lower strip is moved 

 on one place, so that the fore feet of one image are 

 united to the hind feet of the image immediately 

 behind it, the fore feet will be T \r of a step in advance 

 of the hind feet, and the whole series thus broken up 

 will give the appearance in the zootrope of a racking 

 pace, in which the hind limbs slightly anticipate the 

 movements of the fore limbs. 



By sliding the lower strip of paper a little further 

 forward the appearance of a walking pace is produced. 

 Still another move in the same direction and we have 

 a broken trot, and then again a walk. 



This is the concrete expression of the relations given 

 by the chronographic chart Fig. 123. 



With this method persons familiar with horses' paces 

 can recognize each example, and realize its derivation 

 from the others. We have been most ably seconded 

 in these researches by M. Mathias Duval, now professor 

 at the Faculty of Medicine and at the School of Fine 

 Arts. This savant recognized the importance of this 

 method for teaching complicated and rapid movements 

 such as could otherwise only be learned at the cost of 

 much labour by specialists. M. Zecky, professor at the 

 School of Fine Arts at Vienna, has adopted the same 

 method for representing horses' paces. We still possess 

 some very carefully drawn series which he sent us. 



Use of Instantaneous Photography in connection with 

 the Zootrope. — In this method the accuracy with which 

 the paces were represented was entirely dependent 

 on the skill of the artist, and hence it was left for 



