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190 THE PHOTOGRAPHIC NEWS. LMAROH 20, 1885. Method of Printing Floral Borders to Vignette Portraits ” (see page 180 ). Mr. Freeman exhibited several very fine specimens in illustration of his method. A question was asked as to whether orthochromatic plates had been tried for photographing flowers and coloured objects ; but, apparently, no one present had had experience of them. Gloucester School of SCrENCE Philosophical Society. Photograiihic Section. The ordinary monthly meeting was held on the 10th inst., Mr. J. Crofts in the chair. Routine preliminaries having been disposed of, Mr. G. Embrey, F.G.S., exhibited a small installation of electric lighting apparatus, and suitable for use in the dark room. An ingenious but very simple contrivance answers the purpose of throwing the light on to the work in hand, while entirely shielding the eyes, and the addition thereto of a small cap, the end of which is covered with orange paper or golden fabric, effectually renders the light non actinte. The lamp used wis an incandescent one of 2}-candle power. The advantages of such a light for the dark-room were pointed out and gene rally recognized by the members present, amongst them being the facility with which the light can be increased or reduced at will, by the mere turning of a small handle, so that a light as feeble as desired may be used for the commencement of the deve lopment of a very rapid plate, and gradually increased as the plate becomes less sensitive. On completion of the fixing, it is only to take the little cap off the lamp, just as you would remove a lens cap, and you have white light again. The four batteries are contained in a box about twelve inches square, and will fur nish power enough to light two or three lamps at a time if desired. It was estimated that one lamp would burn six hours continually without it becoming necessary to re-charge the batteries, and that the cost of the materials for re-charging would be about 6d. One of the members stated that he had been at a considerably greater expense in fitting up a lamp in his dark-room with a chimney to carry off the impure air, and that he found the heat given off by it so great as to preclude its possible use during the coming summer, and he also attributed the discolouration of a quantity of sensitized paper to the action of the gas fumes. The electric lamp would, he said, remedy all these evils, and occupy less of the working space of his small room, as the box contain ing the batteries could be placed either overhead on a shelf, or on the ground, and the lamp suspended where required. Notts PIOTOGRAPIC Society. The usual fortnightly meeting was held at the rooms, Shake speare Street, on Monday evening last, Mr. G. SHEPPERLEY, President, in the chair, when, after the minutes had been passed and a new member admitted, a more than usually interesting paper was read by Mr. PENDRY upon the carbon process, illus trating his subject afterwards by producing some very fine trans parencies (for window decoration) upon glass, and demonstrating at the same time the single transfer process upon paper and opal. Much satisfaction was expressed by the members present at the simplicity and practicability of explanation afforded them by the demonstrator. Afterwards, some collodio-albumen prints were shown by the Chairman to those assembled, which had been presented to the former Nottingham Photographic Society in the year 1856, and which were consequently regarded with peculiar interest. Manchester Photographic Society. The usual monthly meeting of this Society was held on the 12th inst., Mr. J. S. Pollitt in the chair. The minutes of the previous meeting were read and confirmed. Mr. A. Brothers, F.R.A.S., desired to correct a possible mis understanding which the report of the previous meeting might have conveyed to persons not present at the meeting, when he (Mr. Brothers) showed the photograph of a group of children taken at the Mayor of Salford’s fancy dress ball; and he wished it to be understood that the photograph in question had been taken by Mr. J. White, and not by himself. Mr. T. R. Colley was elected a member of the Society. The Hon. Secretary gave a demonstration of the collodio- bromide process for transparencies. After describing the method of making the emulsion, and exhibiting several small pieces of apparatus which he had found useful in working the process, several plates were prepared, exposed, and developed, and handed round to the members for inspection. The developer he used was similar to the one published by Mr. William Brooks, and the details of the process as given by the Hon. Secretary are as follows : — Collodion. Alcohol ounces Ether 2 „ Pyroxylin ... 374 grains Dissolve 100 grains zinc bromide in a small quantity of alcohol, and add two or three drops of nitric acid, and add to half the above collodion. Dissolve 165 grains of silver nitrate in boiling alcohol, and add to the other half the collodion. Sensitise by mixing the two collodions, drop by drop, shaking well all the time. Spread a small quantity of the emulsion on a glass plate, and examine by transmitted light. The flame of a candle should appear orange or ruby. Add a drop of potassium chromate to test a portion of the emulsion, or to a film spread on glass. A bright red coloration shows the presence of silver in excess. Make up to seven and a half ounces with ether and alcohol in equal parts, and let stand to ripen for twenty-four hours. If to be washed, do not add the last solvents, but pour the whole into a dish for the solvents to evaporate. Break up with a slip of glass or bone paper kuife, and wash in several changes of water till all trace of silver is removed. Drain on blotting-paper, and when as much water as possible has been removed by this means, add a small quantity of alcohol, which will absorb the remainder of the water, and when this has evaporated, dissolve in ether and alcohol, as above, to seven and a half ounces.: Developer.—Solution P. Pyrogallol .. 3 grains Water ... ... 1 ounce Solution A. Potass, carb. ... 75 grains „ bicarb ... 37 „ „ bromide 15 „ Sodium acetate 30 „ Water 3 „ To develop, flood the plate with alcohol and water for about one minute. Immerse in a dish of water till all greasiness is gone. While plate is washing, mix one drachm of A with one ounce of P. Cover plate with this till details are all out, and complete the development by adding additional portions of A and P as re quired. If intensification is found necessary, it can be done after fixing with the ordinary pyro and silver intensifier, viz. :— Pyro 2 grains Acid citrate 2 „ Water ... 1 ounce To -which is added at the time of using five to ten drops of a ten- grain solution of silver nitrate. Fix with hypo or potassium cyanide. Care is necessary, after washing well, to remove all trace of the fixing solation, with— Platinum bichloride... ... ... 1 grain Acid nitric 1 drop Water... 3 ounces Derby PiioTooiiArHic Society. The usual monthly meeting was hold on Wednesday, March 4th. Mr. J. C. Merry occupied the chair, and congratulated the Society on the large number of new members which had come forward since the conversazione. Mr. Arthur J. Cox then read a paper on “ The Artistic Appli cation of Photography,” which he illustrated with numerous photographs, and which contained much sound advice as to the best subjects to choose when on a tour with the camera, also pointing out errors when trying to make an artistic picture. The Society now numbers sixty-eight members. Ualk in the Studio. Photographic Society of Great Britain.—The next monthly technical meeting of this Society will take place on Tuesday next, March 24th, at eight o’clock, at the Gallery, 5a, Pall Mall East.