THE BOOK OF THE LANTERN. 115 



the transparency of such lights, and in a good lantern slide 

 they should be represented by clear glass. 



TRANSPARENCIES ON COMMERCIAL GELATINE PLATES. 



For some inscrutable reason, it used to be the common 

 opinion among those who ought to know something about 

 the matter, that the gelatine process is unsuitable for lan- 

 tern transparencies. The introduction lately of gelatine 

 lantern plates into the market has done much to correct 

 this error ; but still there are numerous persons who hold 

 to the belief that the ordinary gelatine plate, such as is 

 used for negative work, will not produce a good trans- 

 parency. For years I have proved the contrary, and with 

 regard to the quality of the transparencies produced, I have 

 seen few to equal them. 



The first operator who turned out successful work of this 

 character was Mr. Kennett, who has the greater honour 

 of being the first to make gelatine plates a marketable 

 commodity. His method of working was to employ a slow 

 plate, to expose it under a negative in a printing frame for 

 the fraction of a second in daylight, or for a longer time 

 by lamplight, and to develop by either the alkaline or 

 ferrous oxalate method. The plate was afterwards flooded 

 with pyro and silver and toned with gold. 



The introduction of chloride plates, which give beautiful 

 effects, may deter some from trying what can be done by 

 ordinary gelatino-bromide plates. But for the amateur 

 whose time is otherwise occupied during daylight, the latter 

 process has many advantages. The chief one is that, while 



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