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81 THE PHOTOGRAPHIC NEWS. [February 6, 1885. 3. The uranium method of intensification must not be proceeded with till every trace of sulphite is removed from the film, or fogging will certainly result. Allowing to soak for, say, five minutes in each of about six changes of water will probably be sufficient washing ; but a more certain method is to wash rather less thoroughly if time is an object, then to soak for about ten minutes in water to which ten to twenty drops of the ordinary peroxide of hydrogen has been added. This converts the remain ing sulphite into sulphate, which is without effect on the after processes. Change the soaking water two or three times after the peroxide of hydrogen, and then lay in the uranium solution. 4. The uranium solution may contain from one to two percent, of the salt, or a stronger solution may be kept, and a few drops added to the bulk of water required, till the yellow colour is visible. 5. The ferricyanide of potassium should be kept solid. For use, take a crystal or two the size of a pea, and wash them in a current of water for a few seconds till they are perfectly clean and of a clear ruby colour. Then put a dram or so of water upon them, and agitate till the water is yellow. Pour the solution so obtained into a develop ing cup, add to it the uranium that has been soaking the film, and re-apply. Do not hurry the action, but add more ferricyanide solution as required. When the action is complete, wash as usual. 6. If the action of the uranium intensifier does not go thoroughly through the film, the detail in the shadows will be fully intensified, while the high lights will only be partially intensified. The brown ferrocyanide of uranium may be entirely removed from a negative by a dilute solution of carbonate of ammonia. This may save a negative that has got fogged with the uranium intensifier, if the uranium has acted only slightly. Where it has acted thoroughly, a mere ghost of the picture remains, unless the uranium intensifier has been preceded by the mercury and sulphite process, when the image remains as a white mercuric salt. This may be blackened with ammonium sulphide, but such procedure is not practically useful. After intensification with mercury and sulphite, the image may be again bleached with mercuric chloride, and blackened with sulphite; but there is a very slight if any gain in density by the operation, though theory seems to indicate that the amount of mercury should be doubled. NOTES FROM NEW YORK. Presentation Prints—Mr. J. T. Taylor on Lenses— A New Camera—Improved Methods of Developing Dry Plates—The Photographing of Materialized Spirits. At the regular meeting of the Amateur Society on the 13th inst., a resolution was passed authorizing a presenta tion print to be issued and presented to each member at the close of the first year of the existence of the Society— April 1, 1885. Special rules and regulations are specified as to how the committee charged with the matter shall act. It is a subject that is likely to awaken much general interest among the members. Mr. J. Traill Taylor, of the Photographic Times, gave an interesting talk on “ Photographic Lenses and their Functions,” with copious illustrations on the blackboard. He appeared to possess a very complete and thorough knowledge of the subject in hand. He showed a now lens, made by Morrison, in which the lenses were considerably separated from each other. He was applauded by a vote of thanks, and afterwards was elected unanimously as an honorary member of the Society. A compact and novel camera for instantaneous work, the design of Mr. H. V. Parsell, and made for him by W. T, Gregg, was shown. It was in the form of a doctor’s portable medicine chest, neatly covered with black leather, and provided with a leather handle. The size of picture was 2} inches square, and the total weight of the apparatus, with six double plate-holders, loaded, was only 2 lbs. 3 oz. In outward appearance it had no resemblance to a camera ; the exposures were made by a snap shutter, ingeniously arranged to work in the lens tube in the place occupied by the diaphragms. A wide-angle lens, with a fixed focus for objects within six and fifty feet, was adopted, and a supplementary lens-finder employed, making it very easy for the operator to take a shot without being suspected of carrying a photographic apparatus. The neat and well-made appearance, and lightness of the box, were very favourably commented upon. Mr. A. D. Fiske showed a print from a negative of trotting horses going at great speed, which was extra ordinarily good, because of the detail brought out in diffi cult places. His method of development was peculiar, and consisted in using strong solutions of pyro and ammonia, supplemented by rubbing the film on the shadow portions with the finger, and in prolonging the development for from ten to twenty minutes. He noticed that a scum formed on the surface of the film soon after the developer was applied, and by simply rubbing over the film with his finger the scum disappeared, and permitted the developer to act more energetically. Whether the scum would appear on different kinds of plates was not stated. It will form a subject of much interest for future experiment. A camel-hair brush did not have the same effect as the fingers. Mr. George Ripley had noticed that taking a plate out of the developer and breathing on it caused an accelerat ing action, and thought Mr. Fiske’s results might be due to the heat transmitted from the fingers to the surface of the film. A mode of development which he had lately adopted was to have beside him a weak soda or potash solution, and when the high lights appeared well out in the original pyro and soda developer, to at once transfer the plate, without washing, to the free soda solution. He claimed that there was enough pyro left in the film to add sufficient density to the shadows, and the plate could be left for a long time—half-an-hour or more—in the soda solution without danger of fogging. The resulting nega tive would be very equal; the high lights would not be top dense, and the details in the shadows would appear with ample density and crispness. Since my last letter, the first number of Anthony’s Bulletin, in a new and handsome cover, has appeared, and contains an excellent likeness of its new editor, Prof. Chas. F. Chandler. Prof. Chandler has the reputation of being a man of progress, and under his inspiring hand we may look for an improvement in photographic journalism in this country. I learn that a short time ago Mr. F. C. Beach, ac companied by Mr. J. Traill Taylor, went to photograph what wer alleged to be “ materialized spirits,” using extra sensitive dry plates, and the magnesium light. Mr. Beach, being a con tinned sceptic in this line, doubted the ability of the spi its to withstand the intense glow of the mag nesium light, as it was customary to view them by a light so dim that a person’s face ten feet away could not be distinguished. But from prior assurances it was fully understood tint the power of the “spirits” was great enough to endure the effects of the light, and that no dis appointment would occur. A good look at the medium showed th it she was a tall, solidly built woman, dressed in an ordinary loose morning wiapper. She was supposed to sit m a chair in a small curtained place in one corner of the room, and while in a trance state, unbeknown to her, beautiful angelic forms might mateiialize and show them selves at the division in the curtain, and possibly walk out and shake bands with members of the circle. When the focus was obtained by using a lamp, and the lights were extinguished all except a small gas jet as large as a pea, surrounded by greenish tissue paper, some pre-