234 



NATURE OF PHOTOSENSORY PROCESS 



at the bottom. When it is at the left of the shutter, the rod is held 

 by a small projecting spring clip F, which may be released by hand, 

 or more conveniently by an air bulb. To the ends of the cyHndricaL 



Xi^tJJL^ 



-c 



"iP" 





3^ 



T 



/Ocm. 



Fig. 3. Three views of the shutter. The upper drawing is the front view; 

 below that is the bottom view; and below that is a partial section through the 

 shutter. The letters are explained in the text. In the upper drawing the details 

 of the spring release clip F are omitted, because they are given in the lowermost 

 view. Similarly the board to which the shutter is attached is also omitted from 

 the upper drawing. 



