116 



MOVEMENT 



period of exposure, and again advance with a jerk. A 

 series of photographs of fair size can be taken in this 

 way. 



The size we chose was 9 centimetres square, exactly 

 the right size to fit the enlarging camera, and by 

 which they could be magnified to convenient propor- 

 tions. Now, as the continuous film might be several 

 metres in length, the number of photographs that 

 could be taken was practically unlimited. 



Arrangement of the Chronophotographic Apparatus. — 



Fig. 80. — Internal structure of the photographic chamber. 



The necessary elements for taking successive images 

 on a continuous film are united, as we have said, in the 

 apparatus already known to the reader. The back 

 part of this apparatus has a special compartment, the 

 photographic chamber (Fig. 80), in which the sensitized 

 film is carried. To admit light, all that is necessary is 

 to substitute for the frame which carries the fixed plate 

 another frame provided (Fig. 81) with an aperture, the 

 size of which can be varied at pleasure. This is the 

 admission shutter. At each illumination the light 



