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284 THE PHOTOGRAPHIC NEWS. [April 10, 1891. priceless, for example, would be photographs of events which occurred in the reign of good Queen Bess, suppos ing that such pictures were in existence. In conclusion, Major Nott explained that his object in calling attention to this subject was, that photographers generally should understand the conditions on which photographs intended for illustrated journalism ought to be produced. The journals now relied greatly on photo graphs or sketches sent in by outsiders for acceptance. Everyone now uses the Kodak or similar instrument, and if his remarks had tended to assist anyone in his work in this direction he would be amply rewarded. They should remember that haphazard photographs are, as a rule, perfectly valueless, and that care and attention to details are required in the work. Capt. Abney, in opening the discussion upon this interesting paper, regretted that Major Nott had given no information about the transfer of photographs to wood blocks, and he called upon Mr. Carmichael Thomas, the art director of the Graphic, to favor them with a few remarks upon the general subject. Mr. Thomas said that he had come to the meeting quite Unprepared for any speech-making, but he wished to acknowledge to this club of photographers how much the paper which he represented was indebted to photography for many of the pictures which they published. Indeed, in many cases, he said, it was quite unnecessary to send a special artist to scenes of popular interest, as the manager of the Graphic was aware that they could rely uponplenty of photographs being sent in to the office by strangers and outsiders. Mr. Hepworth said that he had been so long connected with the Graphic that he knew something about this subject of illustrated journalism, and the various modes adopted for turning pictures into printing blocks ; but the ground had been so well covered by Major Nott’s remarks, that he merely rose in response to the remark of Captain Abney with reference to the transfer of the photographic image to the engraving block. Some years ago he had made a number of experiments with different inodes of doing the work. He had tried the collodion film, collo- dio-bromide emulsion, the albumen, and various other processes, but he thought, perhaps, that he had worked in a new direction by adapting gelatino-chloride emulsion to this purpose. The method he adopted was to make a chloride emulsion with a very small proportion of gela tine in it, and to rub the paste thus formed on to the sur face of the wooden block with the finger; the block so treated was dried, exposed under a negative, and deve loped by the usual means. The process gave satisfactory results, as far as the speaker was concerned, but on sub mitting the block to a wood engraver, the latter complained that the surface of the wood block had been, to a certain extent, hardened by the chemical process, and made diffi cult to cut with the graver. He thereupon altered the emulsion in different ways, with the result that the hard ness disappeared, but the engraver now contended that the surface of the wood had been made too spongy and soft. As it seemed impossible to hit a happy medium be tween these two extremes, Mr. Hepworth had ceased his experiments. Mr. W. E. Debenham had hoped to hear something of the process blocks which were coming so much into use for illustrated periodical literature of the higher class. In this department there were two directions in which great advances had been made: the one was in the improvement of block processes, and the other in improved machinery by means of which alone blocks could be properly rendered. Until recently it was considered that rotary machines, such as were necessary for rapid newspaper work, could not be made to act with sufficient nicety for process blocks ; but the work of the Marinoni rotary machines had dispelled this idea. Mr. Warnerke advocated, for the treatment of wood blocks, the transfer of an image in greasy ink direct from the gelatine film—that is to say, a collotype transfer; and Capt. Abney, in bringing the discussion to a conclusion, considered that though Mr. Hepworth’s experiments were interesting, the last-named method was, on the whole, best to pursue, probably for the reasons that it involved no wetting of the wood-block, and no film to interfere with the graver. The next paper read was not on the list, but it proved to be one of great interest. The subject was a new method of producing process blocks, by Mr. II. Sutton. This method consisted in obtaining a direct electrotype from a gelatino-bromide plate, the result being a half-tone block, resembling, in all essential features, that produced by the Meisenbach process. Mr. Sutton, unfortu nately, was not very well heard in the body of the room, but we understood his process to be as follows, although here we can only give a mere outline of it. After exposing an ordinary gelatine plate beneath a positive on glass, or an ordinary print on albumen paper together with the negative of a line screen, the plate is developed with alkaline pyro or hydrokinone, and fixed in strong hypo. The plate is then washed, care being taken that the image does not absorb too much water during this necessary operation. Next, the plate is heated on an iron horizontal surface very gradually by a Bunsen burner, and, while this heating is proceeding, a curious change can be observed extending over the surface of the gelatine. The little dots formed by the line screen remain perfectly insoluble, but the gelatine which has been unexposed be tween those dots melts to a certain extent, and leaves the exposed dots standing up in high relief; in other words, the image engraves itself by means of heat. The plate is next dried, and, after being dusted over with graphite to give it a conducting surface, is at once placed in a copper solution in connection either with a battery or with a dynamo machine, as in the ordinary electrotyping process, and a metal block is the ultimate result. The copper solution causes the gelatine to swell to a very slight ex tent, but not enough to blur the image which it bears. Two plates were handed round for inspection, together with proofs pulled from them in an ordinary press. These were certainly of very fair quality, considering the sim plicity of the process employed, and they raise hopes that, as the method comes to be experimented with—as it most surely will be—that it will be found capable of far finer work. Capt. Abney said that the Conference must be con gratulated on having this process brought before it for the first time. Although he was pretty familiar with most of these processes, this one certainly bore the stamp of novelty. He might say, in passing, that on one occasion, when he had dried a gelatine plate in the sun, he found that it gave exactly the same results in the partial melting of the unexposed parts as explained in Mr. Sutton’s paper. Mr. W. E. Debenham thought the utilisation of the quality of gelatine, of agglomerating under the exposed portions when heated, was very ingenious. The process