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the photographic news. Vol. XXIX. No. 1374.—January 2, 1885. CONTENTS. PAGE Photographic Progress During the Past year 1 Coating Paper with Emulsion 1 The Function of the Condenser in the Optical Lantern or the Enlarging Apparatus 2 Northampton Photographic Exhibition 3 Winter Photography. Ry W. D. Valentine 4 Howto Photograph' Microscopic Objects. By I. II. Jennings 4 Taking Photographs by Artificial Light. By Eugen Himly ... 5 Notes From New York 6 Review 7 PAGE Fashionable Photography 7 Notes 7 Russian Correspondence 9 Patent Intelligence 11 Testing Gelatine. By Captain Abney, R.E., F.R.S 12 A Scamper Across a Continent with a Camera. By R. G. Brook 13 Correspondence 14 Proceedings 14 Talk 15 Answers to Correspondents 1G PHOTOGRAPHIC PROGRESS DURING THE PAST YEAR. During 1884 excellent progress has been made in the technical aspects of photography, and more notably in the process of photographing coloured objects, so as to secure degrees of shading -which approximately correspond to the visual intensities of the various colours. Early in the year Dr. Vogel published details of his method of using eosine and azaline as a means of rendering a photographic film isochromatic ; and further researches in the same direc tion have been made by Dr. Eder and Dr. Lohse, the latter gentleman using extract of turmeric root. In connec tion with this subject it is of great interest to note that Mr. Ives, of Philadelphia, calls attention to the fact that, as far back as 1879, he perfected a process of isochromatic photography on collodio-bromide films stained with the chlorophyll of the blue myrtle ; and in the.Year-Book for 1885 there is a striking illustration of the value of Ives’ method ; two reproductions of a highly-coloured chromo lithograph being given, one taken on an ordinary collodio- bromide plate, and the other on a similar plate treated with the extract of the blue myrtle leaves. In connection with emulsion photography we must mention the fact that of late a gelatine emulsion paper has come into use for small work, the tones obtainable having all that range which one is accustomed to in the case of ordinary alb amenized paper. One may expect that during the coming year emulsion paper will be largely used when the light is weak, or when pressure of business necessitates the rapid production of positive copies. Photographers have gradually realised the fact that it is practicable to abolish the unpleasant ruby light of the dark-room, and to substitute yellow or greenish-yellow tints far less trying to the eyes ; and to Mr. W. E. Deben- ham belongs the credit of having made the advantages of yellow light generally known. With respect to the various methods of photo-mechanical printing—such as collotype, Woodbury type, photo-litho graphy, and photo-typography—one has rather to report as to their much more extended use than to enumerate any definite steps in advance as regards the methods them selves ; it is in the production of phototype blocks for the ordinary printing press that photo-mechanical work has most extended, the blocks made by the Meisenbach Co. and others being now very largely used for book and magazine illustration. Photographs of the solar corona have been taken by Mr. C. Ray Woods from the top of the Riffel in Switzer land, and although the results are not by any means so perfect as those obtainable during an obscuration of the solar disc, the photographs possess great value as demon strating the fact that one may hope to obtain valuable records of this kind, even though the sun is shining on the earth with its full force. Mr. Ray Woods’ results show how important it is to perform difficult astronomical work from elevated stations; if, indeed, any further proof were wanted after the experiments of Professor Piazzi Smyth on the Peak of Teneriffe in 1856. It is to be hoped that a permanent solar observing station will soon be established at as great an elevation as that at which Professor Smyth worked. Abney’s experiments on the remarkable effect of heat in exalting the sensitiveness of gelatino-bromide films are of great interest; and one may hope that improvements in working may be the ultimate outcome of these researches. The death-list of the year just past is as heavy as in the previous year it was light; and among those whose names are well-known to our readers, the following have departed:—Mr. J. Henry Dallmeyer, the Rev. F. F. Statham, Mr. H. Baden Pritchard, Mr. 0. Jabez Hughes, Mr. Henry E. Anthony (of New York), Mr. J. Hubbard, Mr. H. Nathaniel White, and Mr. Henry Greenwood. The spirit of enquiring activity which is now displaying itself in so many quarters, leads us to hope that during the year just commenced much good work will be done. COATING PAPER WITH EMULSION. On all sides we hear of the use of gelatine emulsion for the preparation of paper to be used in positive printing, and it seems not unlikely that at no distant date the ordinary pro cess of silver printing on albumenized paper is destined to be largely replaced by a development process in which a bromide, chloride, or bromo-chloride emulsion is used. When describing the various methods of working which give good results on paper, we have repeatedly insisted on the importance of photographers giving due attention to development methods for the production of positive prints, and we now propose to say a few words about the manipu lations incident to coating sheets of paper with gelatine emulsion. It is needless to recapitulate in this place either the directions we have recently given for making emulsion suitable for paper, or the details of methods of coating which we have described from time to time ;* but we will now describe two simple modes of coating paper, which were explained at the last meeting of the Photographic Society of Great Britain, which modes of coating were brought forward by Captain Abney and Mr. Cowan respectively. The first method of coating—that of Captain Abney—is especially of service when only a few sheets of paper are to be prepared for experimental pnrposes, while the method • Vol. for 16S2, p. 450; 1S83, p. 98; 1884, p. 819.