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DECEMBER 10, 1880."] valuable, and should not be thrown away. The prepared paper has a yellowish tint, and for this reason the labora tory or printing-room should not be illuminated by yellow glass ; a feeble white-light is far preferable. As most of our readers know very well, vignetting and fancy printing is as easily conducted with platinotype as with the chloride of silver process, the results, in every case, possessing the cold grey tone inseparable to platinum. This tone, however, much as the absence of much warmth may be regretted, is at a premium with book-publishers, by reason of its harmony with letter-press and engravings. Silver prints never harmonise well with type, but platino type does so very perfectly. Mr. Berkeley was good enough to show us some exam ples of platinotype enlarging, sent over from New York by Mr. Willis, to whom we all know the elaboration of the process is due; these enlargements were secured from small negatives by the aid of electric light, and were ex ceedingly satisfactory, both in respect to vigour and detail. The “At Home” next week will be “The Vander WeydeElectric Studio in Regent Street.” FRENCH CORRESPONDENCE. Meeting or the Photographic Society or France— Paper Prates—Dr. Vogel’s Emulsion —New Transfer Process—Selenium Photometer—Portrait of Fox Talbot—Experiments with Phosphorescent Substances —Lectures at the Sorbonne. Meeting of the Photographic Society of France,—We had a very interesting, and more than usually well-attended, meeting of our Photographic Society on the 3rd December last. A letter from the Mayor of Chalons-sur-Saone was read, informing the Society that the eminent sculptor, M. Guillaume, Member of the Institute, a former Director of the Fine Art School, and ex-Director of the Fine Art Department of the Ministry of Public Instruction, had offered his gratuitous services in executing the statue of Nicephore Niepce. This liberal offer puts an end to what at one time threatened to be a serious difficulty in the way of accomplishing what is nothing but an act of justice. M. Balaguy's Pellicle.—Several competitors have already presented themselves for the Gaillard prize, which is offered for the production of the best dry plates in pelli cle: one of these competitors is M. Balaguy. At the meeting of the Photographic Society, he gave a general outline of his process, without, however, describing the details closely. His sensitive film is on paper. The paper is prepared by first stretching it on a glass plate, to which it is no doubt made to adhere by a caoutchouc varnish, and by this means it can be collodionized with the gelatino- bromide, as well as dried, without suffering any deforma tion. It can be easily stripped off the glass, and is then produced in the form of sensitive pellicle. It is developed in the ordinary way, and if it be desired to have a pellicle without paper, it can be pressed with its gelatine side against a glass plate in its wet state, and the paper can then be removed from the support. M. Balaguy did not mention how this operation should be performed, I will therefore say no more about it; but I have a strong belief that he effects it by interposing caoutchouc varnish between the layer of emulsion and the paper. This is, however, nothing more than a guess on my part. Dr. Vogel's Emulsion—M. Schaeffner laid upon the table a number of bottles of this new emulsion, made from pyroxyline dissolved in acetic acid to which bromised gelatine had been added. He exhibited, also, some very fine plates and prints taken with this emulsion. I am sur prised to find no one has yet given an authoritative opinion on this new product, and I am consequently unable to give an account of the views on the subject entertained by my colleagues. All the bottles of emulsion presented at the meeting were distributed among the members, that they might try experiments with the new compound, and the results of these experiments will, I have no doubt, be reported at the next meeting of the Society. Apropos of this emulsion, a sanitary question was raised at the meet ing : the use of acetic acid was stated to be injurious to health. 1 am, however, persuaded that, if the danger really exists, its effect has been very largely exaggerated. Acetic acid has been used for a very long time in the pro duction of photographic preparations, and I never heard yet of its having deleterious properties. A New Transfer Process.—M. Fish, of Lyons, commu nicated a method of making transfers of line drawings on silver or copper, without the use of light in the second transfer, after that a print has been first taken, as in the carbon process. The substance which he employs, of which he gives no detailed account, is flowed over the paper like an ordinary emulsion. It is sensitized by means of potassium bichromate, and, after being developed and dried in the usual way, the image is applied to a well- smoothed plate of silver or copper. At the end of about an hour, the action of the substance which forms the image is shown by the appearance of a brown tint on the metal, reproducing exactly the drawing. It is caused, no doubt, by a sulphuration or some other chemical modi fication of the metallic surface. The same print on paper will give, according to M. Fish, any number of transfers by contact. At the Ministry of War it is intended to use this process for producing maps on copper, ready for the engravers to work on with the burin. The change under gone by the metal constitutes a sort of electric insulation, and a plate treated in this way can be electrotyped, a deposit of metal being obtained on the parts not affected. This process, when further improved, promises to be of great value. A Selenium Photometer.—As an appendix to a communi cation on the subject of Graham Bell’s photophone, I gave the meeting a summary account of my initiatory attempts to construct a selenium photometer for photographic and meteorological purposes. My experiments have hitherto been very successful; the sensitiveness of the instrument to the faintest rays of light is very great, and I have the best hopes to realise by means of it results of great interest. What strikes me very forcibly is the possibility of being able to supersede entirely the photometer formed on the principle of chemical combination or decomposition. I cannot, however, deny that my experiments have been from the very first of extreme delicacy, and very costly ; but the principle being a sound one, I have sufficient courage and determination to pursue them to the end. I do not belong to the school of those who try to build Rome in a day. Portrait of Fox Talbot.—A portrait of Fox Talbot, taken in photo-engraving, by M. Dujardin, was presented to the Society ; in a short time, no doubt, copies will be published. This tribute of respect to the memory of your celebrated countryman, the third father of our art, is happily ren dered simultaneously with the erection of the memorials to Niepce and Daguerre—another proof that science knows no limits of frontier. Experiments with Phosphorescent Substances.—M. War- nerke, when investigating the ingenious phosphorescent photometer recently described in the Photographic News, observed that the phosphorescent sheen was rapidly extinguished by means of a green-coloured translucid screen. This observation of his is quite correct, and,the same thing happens when yellow and red-coloured screens are used. It is only, however, true in the case of white light. I illuminated some calcium sulphide with an ordi nary lamp, and obtained a very beautiful phosphorescence,