116 ARRANGEMENT OF APPARATUS, ETC. 



The actinic focus is found in the same way, and 

 the camera being covered with a dark cloth, the 

 sulphate of copper cell is clamped in position. 



The light is sufficiently intense for the wet plate 

 process. We therefore proceed to the dark room, 

 and sensitise a plate according to the instructions 

 contained in a previous chapter, drain it as quickly 

 and thoroughly as possible, and place it face down- 

 ward in the dark slide used for that purpose. 



If it was necessary to caution the amateur against 

 touching the sensitised surface with his fingers in the 

 dry process, ten times the precautions are necessary 

 here, as the slightest touch will infallibly ruin the 

 plate. 



We shut the slide and convey the plate in as 

 horizontal a position as possible to the camera, care 

 being taken to avoid its knocking against anything 

 or being shaken during the journey. After insertion 

 it is exposed in the manner previously described, 

 three to six minutes being sufficiently long, and when 

 removed from the camera immediately carried to the 

 dark room. 



Any development suitable for the wet plate pro- 

 cess, is at once proceeded with. The resulting nega- 

 tive, after fixing and subsequent washing, being 

 dried and varnished. 



During the description of this method exception 

 might be taken to needless repetition. We have 

 only one excuse to offer. Having seen numerous 

 failures and the destruction of many plates caused 

 by the neglect of some trifling detail only remedied 



