APPARATUS. 



15 



Abnormal Movements, by Francis X. Dercum, M.D., 

 Ph.D/' 



Figure 1 is a view of the building containing the 

 lateral battery of twenty-four photographic cameras, 

 all of which were used when as many consecutive 

 phases of an act of motion were required. 



Immediately in front of each of these cameras, and* 

 detached therefrom, was placed an electro-photographic 

 exposor, a side section of which is represented by 

 Figure 2, in which A is a continuous band of thin 



Fig. 1. 



rubber cloth impervious to light; the edges of which 

 are bound with strong tape, and arranged to run in a 

 groove, and over two rollers RR which are attached to 

 a frame. 



In this endless band are two apertures 00 of suit- 

 able size, and so arranged that their full openings as 

 they pass each other shall simultaneously take place in 

 front of the center of the lens L. 



The upper and lower edges of these apertures are 

 kept taut by light steel rods attached to the tape binding. 



