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Solution B. Water 1000 c.e. Potassium chloride ... ... ... 130 grammes Solution C. Water ... ... ... ... 500 c.e. Sulphate of iron ... ... ... 24 grammes Citric acid ... ... ... ... 2 „ Potassium bromide ... ... ... 2 ,, The paper should be fully exposed, and then soaked in clean water. Then mix— Solution A ... ... ... ... ... 20 c.c. Solution B ... ... ... ... ... 5 „ Solution C ... ... ... ... ... 5 ,, The more of B is taken, the browner will be the tone. The print is cleared, fixed, and washed as usual. Transfers upon Stones without Grinding off the Preoious Engraving.—A recent invention by the firm of Hyle and Klein, of Baunen, which will be of use to photo-litho graphers, consists of making new and perfect transfers upon stones which have been used a few minutes before for printing, without grinding off the previous engraving. Turpentine is applied with a painter’s brush in the case of recently used stones, while for old stones a dilute solu tion of nitric acid is used. The stone is then again covered with a stronger solution of nitric acid, washed off, and put aside until it is dry. After this, it is treated with a solution which is a secret of the inventors. Within about five minutes the stone will be ready for the new transfer. The same stone may be treated in the same way over again without being ground. The process has been patented in this country. Rapid Hydroquinone Developer.—In the Photographisches Corresponded, Mr. A. Lainer publishes the following hydro quinone developer, which is said to act quickly, so that the exposure may be materially shortened, giving at the same time very intense half tones: — Solution A. Water ... ... ... ... ... 900 C.C. Sodium sulphite ... 40 grammes Ferrocyanide of potassium ... 120 33 Hydroquinone ... ... 10 33 Solution B. Caustic potash ... ... 50 grammes Water ... 100 c.c. For use are mixed — Solution A ... 60 c.c. Solution B 2 >» The following formula acts as quickly as the previous on but gives softer negatives : — Solution A. Water ... ... 950 c.c. Sulphite of soda... ... 30 grammes Ferrocyanide of potassium ... ... 90 33 Hydroquinone ... ... 10 13 Solution B. Caustic soda ... 30 grammes Water ... ... 90 c.c. For use, mix— Solution A ... 60 c.c. Solution B ... ... 12 3, The Photographic Society of Great Britain.—The annual dinner will take place at the Cafe Royal, Regent Street, February 9th, at 6.30. Tickets (6s. each) may be obtained of Mr. W. England, 7, St. James’s Square, Notting Hill, W. ; or the Secretary of the Society, 50, Great Russell Street, Blooms bury, London, DEVELOPMENT.* BY. J. K. TULLOCH, M.B. I have many good negatives developed with all the usual alkalis, alone and in combination ; yet I cannot say that after all my labour to discover the best, I yet know which is best. I have abandoned everything but ammonia and pyro, and am getting on certainly as well, if not better, than when I used the others. By way of justifying my present position, I will give a few conclusions which in the meantime, at least, seem to me to be warranted. Using in every case pyro, I find that potash gives a beau tifully delicate image, full of detail and of exquisite gradation, but not sufficiently obstructive of light to make a good printer. Even when made very dense, much of the half-tone is lost by being not opaque enough to impress its strength on paper. For this reason there is to my eye a peculiar oily softness (so to speak) about a potash-deve loped picture, fascinating to begin with, but soon getting distasteful. Soda gives a different effect; it gives an image with more pluck and obstructiveness to light, but in the process it buries detail. I am quite convinced of this; I have examined microscopically the image pro duced by soda as against that produced by ammonia, and find this to be the case. Rule a number of fine lines upon a sheet of white paper, photograph this, cut the plate into two pieces, and develop to the same density, one in soda and one in ammonia. My experience is—and I have tried this several times—that the ammonia-developed plate will show the lines much clearer and sharper than the soda. I can not explain why this should be. There is less risk of fog with soda than with ammonia, and yet somehow the deposit seems not to be confined by the same keen edge. Many of my best pictures have been produced by a soda developer, and I dare say that, for large work, it is probably the most reliable alkali; still, it has that drawback where the picture must be delicate and fine, as for lantern slides. One very good point about soda is its great power of giving density with over-exposure. Indeed, there is great latitude of exposure using soda. To come now to the ammonia pyro developer, which, in spite of many rivals, has no superior : Perhaps the first point to consider is the question, Why should the various formulae differ so completely the one from the other? Without taking into account extraneous ingredients such as soda, sulphite, citric acid, you will find that the three necessary ingre dients differ very widely in their proportions. To begin with, there are many different makes of plates in the market, each one working better with one composition of developer than any other. In the second place, one man works chiefly landscape, another portraiture. A deve loper safe enough for studio work would be eternally getting the landscape man into trouble from over-expo sure, therefore he gradually alters his developer to suit the risk of over-exposure rather than under-exposure. The real difficulty in development is not got over by getting a so-called grand developer. The difficulty is first to know when your picture is there before you, neither more nor less, and the only other item—and this only a small matter—to hit upon a good working plan suiting your plates, and over which you have the necessary con trol. Having said so much, you will be prepared to hear that I have no developer in particular to recommend. I think, however, I can say something to the point, especi ally to beginners. First analyse any formula you may * Concluded from page 71.