260 THE BOOK OF THE LANTERN. 



Another camera which is made purposely for lantern- 

 slide negative making has been recently introduced by 

 Messrs. Mayfield & Cobb. This will, when folded up, easily 

 go into the pocket, and is used like the last-described 

 whilst held in the hand (see fig. 69). 



FIG. 69. 



A great deal of attention has lately been aroused with 

 respect to so-called detective cameras. They would perhaps 

 be better described as concealed cameras, for there are many 

 reasons why they cannot, except by some happy conjunc- 

 tion of circumstances, be used in the detection of crime. 

 Their manufacture has certainly been brought to grea^ 

 perfection, and a wonderful amount of ingenuity has been 

 displayed in their construction. From experience I can 

 speak most highly of the good pictures which can be pro- 

 duced by them. But one essential condition must not be 

 absent; such pictures want absolute sunshine. I give 

 three examples of these detective cameras. The first, 

 Watson's (fig. 68), is a leather-covered box, containing as 



