A Manual Of Photography

MR. CUNDELL’S PROCESS. 221 these solutions are about to be applied to the iodized paper, they are to be mixed together, in equal volumes, by means o a graduated drachm tube. This mixture is called the gallo- nitrate of silver.” As it speedily changes, and will not keep 1 more than a few minutes, it must be used without delay, and ought not to be prepared until the operator is quite ready o apply it. . -.„ 9. The application of this " gallo-nitrate to the paper is < matter of some nicety. It will be found best to apply it in re following manner :—Pour out the solution upon a clean slab o plate-glass, diffusing it over the surface to a size corresponding o that of the paper. Holding the paper by a narrow upturned margin, the sensitive side is to be applied to the liquid upon slab? and brought in contact with it by passing the lingers gently over the back of the paper, which must not be touched with the 10. As soon as the paper is wetted with the gallo-nitrate, it ou Ait instantly to be removed into a dish of water ; five or ten seconds at the most is as long as it is safe at tins stage to leave the paper to be acted upon by the gallo-nitrate ; . in that space of time it absorbs sufficient to render it exquisitively sensitive. The excess of gallo-nitrate must immediately be washed off bv drawing the paper gently several times under the surface o water, which must be perfectly clean ; and being thus washed, it is finished by drawing it through fresh water, two or three times, once more. It is now to be dried in the dark in the manner described in § 7; and, when surface-dry, it may either be placed, while still damp, in the camera, or in a portfolio, among blotting-paper, for use. If properly prepared, it will keep perfectly well for four-and-twenty hours at least, preserving all its whiteness and sensibility. 11. The light of a single candle will not injure the paper at a moderate distance ; but the less the paper, or the exciting solution, is unnecessarily exposed, even to a feeble candle-hg, the better. Common river or spring water answers perfectly o wash the paper, distilled water being required for the silver solutions only., i_ of 1 - ^allo-nitrate, while recent, may be removed from by " Me strong ammonia, or by the cyanide of potassium.„ The third process is that of 12 The Exposure In the Camera, for which as the operator must be guided by bis own judgment few directions can be „„I few are required. He must choose or design his own subject ■ he must determine upon tile aperture to he used, and