CHAPTEK XIX. 

 PRINTING ON BROMIDE PAPER. 



THIS printing process is on the whole, perhaps, the most 

 satisfactory and convenient of all for the photo-micrographer. 

 The author always produces by this process prints intended for 

 special purposes of exhibition, which is a fair guarantee of his 

 own opinion, at least. 



The photo-micrographer whose time is, perhaps, pretty fully 

 occupied with other business will find the bromide paper 

 process convenient from its celerity, and satisfactory on account 

 of the beauty of the results that by a little practice may be 

 obtained. There are certainly difficulties in the process, but 

 as they will all be overcome by care and practice, they need 

 not appal us. 



The process is one of exposure to artificial light as a rule 

 and development, by ferrous oxalate generally. There is no 

 protracted period of printing, no watching of the progress of 

 printing, no toning nor serious washing before fixing. 



To attain speedily to success, and to ensure repetition of success 

 with the same or similar negatives, the worker should in the 

 first place obtain a standard light. A u regulator gas-burner " 

 or an oil lamp always turned to the same height, or a standard 

 candle, or a fixed length of magnesium ribbon, or wire, or a 

 " unit lamp," any of these is suitable. We may also fix either 

 a standard distance from the radiant, varying our exposure, or 

 we may fix upon a standard exposure, and vary our distance 

 from the radiant. Our own preference is to have a normal 

 distance from light to sensitive surface of, say, 18 inches, and 

 to vary the exposure according to our negative, and this 

 practice we recommend to beginners, though the more 

 experienced will find a marked advantage, without introducing 

 insuperable difficulties, in varying both distance and exposure 



