320 



HISTORY OF CHRONOPHOTOGRAPHY. 



paper (fig. 15). When the whole was wound up round its spool before 

 being put in. the film was protected from light by outer layers of 

 opaque paper; and when the work was done and the film was wound 

 upon the other spool it was equally protected by the other terminal of 

 opaque paper so that it could be removed from the apparatus in the 

 light without becoming clouded. 



This apparatus, which was easily used, sufficed for three years for 

 the writer's researches into the motions of man and of animals. Like 



Muy bridge, Anschiitz, 

 and Demeny, he aimed to 

 obtain, I >y Plateau's 

 method, the reproduction 

 of the analyzed motions. 

 At the exhibition of 1889, 

 azootrope moved by elec- 

 tricity showed animals 

 in motion, as well as men, 

 birds, horses at different gaits. But since the zootrope does not allow 

 many figures to be shown, the writer was restricted to exhibiting short 

 movements. He therefore cast about for methods of showing scenes 

 of long duration. 



No. 10. ( 'hvonopkotogra/phic jwojector, 1893. — This apparatus carries 

 an endless belt of photographs to the focus of an objective which pro- 

 jects them upon a screen. Fig. 16 shows the path of the rays in the 

 projector. A pencil of parallel rays, reflected by a heliostat comes 



from S, and falls upon a convex lens /,. This pencil brought to a 

 focus, passes at t through a hole in a diaphragm, meets the shutter- 

 disk r/, which is turned by a crank, passes through every window thr.t 

 comes, then diverges and, meeting the lens /.,, similar to the first, regains 

 its parallelism, is reflected at 45° from a mirror forming the lid of the 

 box, falls vertically upon another mirror at the same inclination, and 

 now passes to the objective. But in this last part of its course it 



