42 



PHOTO-MICROGRAPHY 



coarse a grain, and does not seem able to give the minute details which are readily 

 shown with the Nikko. Taking a piece out of its case (of course in the dark room, 

 one ruby fabric), we lay it face downwards on the negative placed in an ordinary 

 printing frame. Advancing to a naked gaslight, with the face of the printing frame 

 resting against the coat, we place it — the face of the negative — in front of the light 

 at a distance of one foot, moving it in that plane up and down or in a circular motion, 

 so that the bright part of the flame strikes upon all parts of the negative equally. 

 If this be not done, it is very probable that the print will be unequally exposed, 

 and the final result will app'ear uneven. One point must here be mentioned ; it 

 occasionally happens that a very good negative has been obtained so far as applies to 

 the object, perhaps a most difficult diatom, but the light, through some oversight, or 

 perhaps through a small portion of the lime spurting off during exposure, is not equal 

 all over the plate, a most provoking occurrence ; but it can, if not too bad, be readily 

 remedied. Whilst exposing the print before the gas it is not difficult to hold a 

 blackened card in such a manner as to shade the thinner part, whilst allowing the 

 denser portion to be exposed. This requires a little practice, more especially to know 

 how much more exposure the denser portion should have. Then, too, the card must 

 not be held still but kept moving over the picture, otherwise a line of demarcation, 

 hard and defined, will inevitably result across it at the junction of the covered and 

 uncovered portions. 



Having now exposed our print what we think a sufficient time (with a good 

 negative of a proboscis it will probably only want from twenty to forty seconds), we 

 at once return to the dark room, take out the paper, and immerse it in water, taking 

 care that the whole of the paper is thoroughly covered. After a few seconds, say 

 about ten, the paper will stretch itself out, and this indicates it is ready for the 

 developer. The water is drained off thoroughly, and the print placed paper side 

 down upon the dish. Equal parts of the hydroquinone and soda developer (see 

 p. 33), (about half an ounce of each is sufficient for a quarter-plate print) are then 

 flowed over it. After a few seconds, much quicker than in the case of the negative, 

 a positive image comes into view. The photographer must keep his eye now fixed 

 upon the picture and not let his attention be attracted to anything else. It should 

 be developed till all the details of the image are well out, and then the developer 

 instantly poured off and the picture allowed to drain for a few seconds, say three ; in 

 which interval, if he notices, he will detect a grey look coming over the whole print, 

 which he is apt to think will spoil it. This is not so, for after washing well and 

 placing in the hypo, such greyness entirely disappears, leaving a beautifully black 



