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August 28, 1891.] THE PHOTOGRAPHIC NEWS. 615 say again, with one of the profoundest living psychologists, who emphatically calls “Wundt’s ‘theory’ the flimsiest in the world.” So much for Mr. Wheeler’s only accepted theory. I have shown the sensationalists have another theory. Finally, all I have to say is, that since Mr. Wheeler seems to be innocent of the literature written against Wundt, Helm holtz, and Co., it is useless to open a discussion. It only remains to state our observations are in no sense “ judgments,” but pure sensuous impressions. Finally, I would recommend Mr. Wheeler to the works of Stumpf, Schon, Volkmann, Hering, and others. P. H. Emerson. Proreedngs of Societes. PHOTOGRAPHIC Society of Great Britain. At the technical meeting of this Society held on the 25th inst. the chair was occupied by Mr. W. E. Debenham. The subject arranged for the discussion of the evening was “ Photographic Printing Processes,” and it was opened by Mr. Chapman Jones, who said that he took interest in two printing processes only, the carbon and the platinum processes. Photo graphy was a recording process, and as such permanency was of the first importance. In the matter of colour, we ought to be prepared to give up a little for the sake of permanency. With the carbon process, however, any colour could be obtained, and if in time the colour did change somewhat, the print could not be said to fade. Silver prints did not always fade, but there could be no guarantee that they would not do so. Silver prints that he had made himself he had not found to fade ex cept when he had experimentally prepared them with a view to fading. Bromide prints had been called permanent, but here again they had been found to fade, and, therefore, the title was not justified. Mr. F. Ince had found carbon tissue to stick to the negative and spoil it. Mr. Chapman Jones asked whether Mr. Ince’s negatives had been varnished. Mr. Ince said they had not. Mr. Chapman Jones said that the object of varnishing the negative was not to preserve it when put by, but to enable it to withstand injury whilst printing. Mr. Holiday wished to know if a silver print fixed without being toned was as permanent as a toned print. He considered the colour of the untoned print was so much more beautiful and artistic than the cold tone of the ordinary photograph. Mr. W. England said that thorough toning was conducive to permanency, and so was a thorough washing. Mr. A. Mackie said that a thorough fixing was also necessary to permanence. He advised the use of two fixing baths in succession. Mr. Chapman Jones said that long washing was not neces sary. He believed that, by proper treatment, a print might bo thoroughly washed in half-an-hour. He washed for a few minutes, then immersed in a dilute solution of iodine until the print showed blue on the black, and it was then washed again and dried. The Chairman said that Mr. W. K. Burton had found that such a heavy deposit of gold might be given to a silver print that it would withstand the action of a solution of bichloride of mercury. This solution entirely bleached an untoned silver print. A print containing so much gold would have greater probability of permanency. Mr. T. Samuel had made prints thirty years since that were still unchanged. He also had some that were made by Mr. Melhuish twenty-five years since. These prints were as fresh as ever. They were toned by a process published at the time by Mr. Melhuish, as one giving black tones. The Chairman observed that Mr. Chapman Jones had said that we ought to be prepared to give up something in the way of colour for the sake of permanency. No doubt, for purposes of record, that was true, but if it was found that in some particulars we could get a better print by silver than with carbon or platinum, he would say let us have the better print as well as the permanent one. The point in which he con sidered an albumen print to be better than one in carbon or platinum was in the matter of gradation. A carbon print was generally somewhat deficient in rendering gradation in the lights, and a platinum print similarly deficient in the shadows. As to the matter of colour, he considered that, as well as the condition of surface, whether matt or glossy, to be matters of indifference compared with a truthful rendering of the grada tion of the negative. For colour, however, the public had decided in favour of that of a successfully toned print on albumen paper. Mr. T. Bolas enquired of Mr. Holiday whether he found the colour that pleased him at one time did so at another. Mr. Holiday replied in the affirmative. Mr. Bolas thought it would have been the other way, and that the appreciation of colour was a shifting quantity. Mr. Chapman Jones said that an infinitesimal amount of silver served to give a strong colouration. If this colour changed by fading, there was not enough of the metal to have the image brought out again. He thought that this was a fact which had been overlooked in a recent article on the subject in one of the journals. Mr. A. Mackie asked whether anything more had been heard of the iron printing process, specimens of which were shown by Professor Meldola at a lecture at the Society of Arts. It was replied that Professor Meldola’s lectures were shortly to be published, and that occasion might be utilised to obtain further information on the subject. Mr. A. Glasse said that the character of a print depended much upon that of the negative from which it was made. With the strong negatives of former days it was easier to get a vigorous print such as might be expected to withstand the influence of fading, than with the thinner negatives now pre valent. Then he thought that the lai ge amount of albumen now spread on the paper was conducive to fading. Formerly the coating of albumen was very dilute. A silver print was the richest in colour and most vigorous, and the best that could be given to the public or to the art world. The Chairman thought that two statements that were frequently made concerning differences between the prints of the present day and those of thirty years or so since were mistaken. It was asserted that negatives were made much more intense then than now, and that the albumen coating was mneh lighter than at present. With regard to density, although it might be that the tendency of the inexperienced was to get too great density with pyro-developcd collodion negatives, and to get too little density with gelatine negatives, he believed that the standard of experienced workers was about the same now as formerly. The time of the exhibition of 1862 was a convenient epoch for reference, and as one set of examples he mentioned the work of Mr. England, taken at the exhibition of that year. He would ask whether the negatives then taken were not of about the same density as what would now be con sidered right. As to the albumen coating, it was considerably earlier than that that the practice was to use albumen with as little water as was just necessary to dissolve the salt used. Mr. England said that the negatives referred to by the Chairman were of about the density of those of the present day, and that as strong an albumen coating as could be given was applied to the paper. It was asked whether sulphur was not a constituent of albumen, and Mr. Bolas replied that that was a moot point. Sulphuretted hydrogen was formed when sulphates were present in company with organic matter. When casks of spring water were sent to sea, it was found that the sulphate when present became decomposed, and so much sulphuretted hydrogen set free as to cause the water to smell and give the idea of some dangerous putrefaction having set in. The water was, there fore, left open for a time to allow of escape by evaporation and re-oxidation into sulphate. Northern Tasmanian Camera Club. The second annual meeting of the above Club was held at Mr. R. L. Parker’s rooms, St. John’s Street, Launceston. Mr. R. L. Parker occupied the chair. After the minutes of the