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282 THE PHOTOGRAPHIC NEWS. LMAY 1, 1885. FRENCH CORRESPONDENCE. Dark-Box for Tablet of Plates—Phototype Pro cesses. Dark-Box,—lam surprised that noonehasyet constructed a negative dark-slide for containing plates or pellicles successively superposed as in blotting tablets or drawing blocks. A dark-box of this kind would be invaluable, especially for pocket apparatus, because only one would be required in use with a suffcient number of plates. I have been wondering whether it were possible to carry out such an idea practically, and after thoroughly studying the question I have given nay plans to a cabinet maker to be carried out, while with the help of the wood-cuts I can pre sent it to my readers. My dark-box is composed of three distinct parts: 1. The block A B C D consisting of an ebonite or wooden tablet to support the superposed sensi tive plates, D D' D", &c; 2. A case EFGH, enclosing the block; 3. A metal plate I J, terminating at I by a sheet of steel serrated at its two extremities, RR'; this plate can be moved from front to back of the case from E to H by four screws moving in fixed sockets. Each turn of the screw corresponds to the displacement of a plate one way or the other to the extent of two millimetres. The heads of the screws V V' V” V"' slightly project from the surface of the case. Now for the action of the dark-box. Let us suppose it is for twelve plates of 1 millimetre in thickness, the whole width from F to G is only 33 m.m. When placed at the back of the camera in its destined groove, all shut up, and the metallic slide I J brought up to H G, so as to allow the block to drop easily into the case without the last plate, C D', rubbing against I J. To expose, the case EFGH is drawn down as in the position shown in fig. 1. That done, the case has only to be pushed up again ; but before so doing turn the four screws to push IJ back two millimetres, which distance is marked on the screws. The sheet is then placed between the first and second plates, and the case is pushed up into its place. The two sharp parts of the metal plate RR' (fig. 2) cut the two bands of paper gummed on the edges of the plates at K K‘ and K" K'", the first plate C D is detached and falls between HG and the metal slide I J. To expose the second plate one has only to draw the lens back two milli metres and open the case as before. When exposed, I J is screwed back the two millimetres and remounted, this time passing between the second and third plates, when the former is detached from the block, and the same process i s continued throughout the whole series of plates until the metal slide is pressed against the tablet A B. Figure 1 represents the side view after the exposure of three plates, the metal slide IJ so placed as to detach the fourth when pushed up. When using pellicles they must be very flat, and the block will be lighter and able to contain more ; but care must be taken to leave a space of one millimetre be tween each, to allow for the variation in the thickness of supports. The metal must not be allowed to scratch the surface of the emulsion, and that is why it should be un screwed a little more at the upper part, so that the back of the plate should not come in contact with it. If glass be used, a dozen plates weighing from 135 to 140 grammes will, when enclosed in such a dark-box, only amount to about 200 grammes altogether. To avoid any possible transmission of light it would suffice to fold a piece of thin black or red paper over the back of the glasses. This seems to me the most convenient and simple system of any I have studied. The mounting of the tablets or blocks does not present any difliculty. Place the plates in grooves at the requisite distance apart, and glue on to the two longest edges the two strips of paper destined to maintain them in their position. 1 his kind of dark-box seems to be most suitable for small apparatus such as my photographic En-cax. Phototype Processes.—The question of photographic pro cesses is one of the most interesting of the time. Every where are improvements sought after in the manner of direct transformation of photographic negatives into typo graphic blocks. V Illustration, the best of our French illustrated journals, has just published its Salon number, giving a good many reproductions of pictures tobe exhibited at the coming Salon on May 1st. M. Manzi’s photo engraving process has been used, that which has been ap plied with so much success in MM. Boussod Valadon and Co’s, studios. The day is not far off when these processes may be used for all illustrating purposes. The method known as the Talbot process, by which a copper plate is bitten through a gelatine film, is one of the best I know for getting the effect in proportion to the action of light. 1 will describe the whole operation another time. Leon Vidal. Patent Untelligence. Applications for Letters Patent. ■5014. John Kershaw, 10, Quadrant, Buxton, Derbyshire, for “Improvements in the shutters of photographic cameras.’’— 23rd April, 1885. 5052. John Clayton Mewburn, 169, Fleet Street, London, for “ Improvements in the production of pictures with the aid of photography.”—[Louis Jacques Henri Cellerier, France).— 23rd April, 1885. 5103. George Frederick Redfern, 4, South Street, Finsbury, Middlesex, for “ Improvements in the reproduction of en gravings, drawings, and the like.”—[Pierre Edmund de Saint Florent, France.)—2ithApril, 1885. 5181. George Sylvester GRINISTON, 3, Mycenae Villas, Mycenae Road, Westcombe Park, Greenwich, S.E., Kent, for “Improvements in instantaneous shutters for photographic purposes.”—27th April, 1885. Patents Sealed. 6688. Samuel Dunseith McKellen, 18, Brown Street, Man chester, Watch Manufacturer and Jeweller, for “ An improve ment in cameras for photographic purposes.”—Dated 23rd April, 1884. 6743. Norman Macbeth, Victoria Foundry, Bolton, Lanca shire, Engineer, for “ Improvements in the production of printing surfaces by the aid of photo-reliefs.”—Dated 24th April, 1881.