3^ THE A B C OF PHOTO - MICROGRAPHY 



I believe there is not a single reagent among 

 the very many now obtainable which will not 

 develop a properly exposed plate in a satisfac- 

 tory manner if carefully used. Of course 

 some are better than others, but all can be 

 used. The developer should bring out all 

 details to the very finest, and it should pro- 

 duce the fullest density required without chok- 

 ing or obliterating any of them. It should 

 not produce chemical fog or stains under any 

 circumstances, and should not be liable to any 

 considerable loss of density in the fixing bath. 

 Pyrogallol in the hands of an expert fulfils all 

 of these requirements, but it is so sure to 

 stain the hands that few amateurs care to use 

 it in these days of cleaner developers. The 

 combination of two or more reagents possess- 

 ing different qualities has been found most 

 satisfactory. I lay no claim to having been 

 the first to so employ them, but I do claim 

 that so doing, in my case, was the result of an 

 original thought brought about accidentally. 

 I was experimenting with eikonogen (then just 

 introduced), finding it a very energetic devel- 

 oper and extremely rapid as compared with 

 hydroquinon, which I had been using for some 

 time with satisfaction, but it was impossible to 

 obtain requisite density in the negative. I 



