112 THE A B C OF PHOTO - MICROGRAPHY 



upon the screen by an equally good light. 

 It should stand without loss the searching 

 rays of the electric arc, and may truly be 

 termed* good if it does so. 



Excellent plates for this purpose are now 

 furnished by all the leading makers of nega- 

 tive plates. I have used them all and can 

 testify to their uniformly good qualities. 

 They vary considerably in sensitiveness and 

 in the tones produced by given developers. 

 I have found it most satisfactory on the whole 

 to use the particular one recommended by 

 the makers, who seem, one and all, to have 

 worked out the best methods in each case. 

 I have already elsewhere spoken of the entire 

 satisfaction with which I have used exclusively 

 for over a year past the Forbes negative 

 plates, to which must be added those for 

 lantern-slides, which I have also employed 

 during the same period of time with such 

 uniformly good results as to leave no desire 

 to change. They are quick, give brilliant 

 pictures, have no tendency to fog or frill, 

 allow great latitude of exposure, are very 

 easy of manipulation and cheap. What more 

 could one desire? 



Two methods of making lantern-slides are 

 open to the photo-micrographic in common 



