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21420 cosct-sa---a APRTL 27, 1883. | THE PHOTOGRAPHIC NEWS. 259 grain, and we hope to present our readers with a specimen before long. Fatty ink photographs with a tolerably open and free grain—indeed, just such productions as Mr. Sprague’s “ ink photo,” which forms our supplement this week—are by no means new; as we have before us a work published at Paris in 1855 which is illustrated by a stippled photo lithograph as nearly as possible identical in appearance with the Sprague “ ink photo ” of to-day. Long numbers of such productions can be easily printed by means of a lithographic press or machine ; but we imagine that if the picture of Mr. Dixon’s lion were transferred to zinc and etched in relief by the chemigraphic method, printing from the block would be a much more expensive process than that adopted, and that the results would be considerably inferior. If it be desired to produce an ink photograph which will yield a block suitable for ordinary commercial printing, a method must be adopted which yields a coarser and more open grain ; and it is interesting to know that almost any degree of coarseness or fineness may be obtained by an extremely easy method, and one which requires but few appliances beyond those to bo found in every photographic establishment. We refer to the starch method of Asser, a process which is now over twenty years old ; and the accompanying illustration is from a zincographic relief block, obtained by putting down the Asser transfer on a zinc plate, and etching the metal into relief by the chemigraphic method, which will be found described in detail in our last volume, p.p. 673, 690, 706, 738, 770. The following description of the method by which we made the transfer, and put it down on the zinc plate, will doubtless be of interest to our readers. A sheet of unsized paper—white blotting paper, in fact—was laid on a slab of plate glass, and dabbed over with a thin starch paste, a soft sponge being used for the purpose, and care taken to only apply so much starch paste as would fairly sink into the texture of the paper. The sheet was next dried, after which it was sensitized by being floated (starched side downwards) for five minutes on a five per cent, solution of potassium bichro mate, and it was hung up to dry in a moderately warm room. When dry, it was exposed under an ordinary nega tive for about two-thirds of the time which would hav THE OLD CHURCH OE ST. NICHOLAS, AT CHISWICK. A Photographic Etching, from a Transfer bp the method of E. I. Asser, of Amsterdam.