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JVEMBER, 2 1883.] THE PHOTOGRAPHIC NEWS. 695 It is scarcely necessary to say that the prints must be so piled UP asto ensure the exact superposition of the corresponding parts of the various impressions ; and Mr. Thomson’s method of working to a register paper attached to the negative is easy, and will be found very convenient; but we have found a slightly modified system rather more convenient in actual practice. A A.—The die. B.- The moulded lead block or plate, 10 by 8 in. C.—Block of cast iron, which is not required if a good solid table is at hand to lay the lead on. D.—The mallet. F.—The cut paper as it falls out of the die. The round hole in the centre of the die, A, is to admit a pencil for pushing out the cut paper. One of more elaborate construction could be made, with a spiral spring, for the same purpose. E.—Negative showing the register paper in position. Any number of these papers can be cut from waste albumenized paper. Two small patches of black varnish (say, about one-eighth of an inch in diameter) are painted on the negative, just beyond the limits of the portion required to be included in the stamped-out picture, one of these patches being, let us suppose, at the top, and the other at the bottom. In the centre of each black patch a small round hole is cleared out with a pointed tool, so that the main patch prints white, and the central spot black. The prints which are to be cut at one time—perhaps three or four dozen—are now impaled on a couple of pins, care being taken that all face in the same direction, and that the pins run exactly through the register dots. The circumstance of the paper expanding rather more in one direction than the other affects the register to a trifling extent but not so much as to occasion any inconvenience. Instead of cutting on a leaden plate, many persons prefer to use a board or slab of lime-wood, which has been sawn transversely, so that the end of the grain shall be directed towards the cutting edge of the die. FRENCH CORRESPONDENCE. MM. Encausse and Canesie’s New Toning Solution and PRINTING Ink—M. STEBDINO's Automatic Camera —Increase in Rapidity of Taillfer and Clayton’s IsocIROMATIC Plates-Schleicher and SCHULL's Fabric—M. FRANCAIS' Lens. New Toning Solution.—I have lately had occasion to experiment upon a new double salt of gold and calcium, manufactured by Encausse and Canesie, for toning pur poses, requiring no secondary salt to assist its action. It is used in the proportion of one gramme of the double salt to a litre of ordinary water; it is not necessary to have distilled water. The solution keeps well, and its toning properties increase with age. It is not affected by sun- light, therefore a large quantity may be prepared iu advance ; the only precaution to be taken is to let it stand forty-eight hours before using, and it lasts until the bath *8 exhausted. With five grammes of this salt dissolved in five litres of water, more than a ream of paper has been toned. The advantages of this toning bath are therefore very great, and 1 may add that no previous washing of the prints is necessary, as the nitrate of silver is transformed into chloride of silver, and is recovered by filtering. This product, thus simplifying one of the most important operations in printing, deserves to be taken into notice from an economical point of view. Printing Ink.—The same firm also makes a special print ing ink having the advantage of drying very quickly on paper, while it remains moist on the slab and the rollers. The manufacturers have utilised the absorbent power of paper to effect the drying, while the slab, rollers, and other materials used in the machinery do not absorb it. After experimenting with this production I do not hesitate to recommend its use in phototype work. Camera for Endless Bands.—M. Stebbing has effectually improved Bertsche’s automatic camera so that it can be used with the endless bands of gelatino-bromide paper. The band is rolled on a reel placed at the left-hand side, and rolls up on another at the right, passing across a fixed plate of glass, the posterior surface of which is at the exact focal length from the lens. Each time a fresh portion of the band is unrolled and appears behind the glass, it is pressed against it by a slide at the back. This little apparatus only gives pictures six centimetres square, but large enough to be seen by using a magnifying glass, and they may be enlarged from four to eight times their size. Pieces of M. Thiebaut’s reversible pellicle paper make excellent end less bands by gumming them on to a strip of suitable material. Rollers are to be had ready fitted with the bands capable of taking one hundred pictures. I think a camera and apparatus of this description will be of great use to those desiring to carry as little weight as possible, besides avoiding the necessity of conveying fragile plates. I have adopted an automatic arrangement by which each exposure made may be counted. This apparatus is not a plaything, but an accurate instrument to be used and relied upon by anyone desiring to have a portable method of taking photo graphs. 1 take a greater delight in describing M. Steb- bing's camera, because, although constant improvement is being made in large ones, no one makes an advance in these small apparatus of a really useful and substantial nature. Isochromalic Plates.—These Anglo-French plates of Taillfer and Clayton have been lately improved, and are equal to Monckhoven’s in rapidity. Results obtained by me from these plates are perfect. One can now no longer hesitate to use them when pictures are to be reproduced, or subjects containing certain refractory colours, as the rela tive tone is preserved. Schleicher and SchuWs Fabric.—Patterns have been sent me of a special fabric suitable for printing upon. I have examined it from a photographic point of view, and find that it is supplied in rolls of 0 96 metres in width and 32 metres in length, and will be very useful for carbon transfers, enlargements of all kinds, and phototypes. The agent for it in Paris is M. Eugene Charavay fils, 8, Quai du Louvre; but 1 daresay the house of Schleicher and Schll has an English depot. The cloth is made in various colours—pink, blue, yellow, grey, and green, as well as white. Multiple Focus Lens.—During my summer holiday, I used a lens by M. Franais. It was rectilinear, and had nine distinct combinations varying in focus between 13 and 40 centimetres. My pictures have been taken at all these different focal lengths, while preserving the qualities of a good lens; it cannot, therefore, be too highly recom mended. In this case, one lens—or even two—would not have sufficed. A set of these various combinations is indispensable to the serious worker, and this of M. Fran- ais is best constructed to satisfy various requirements. Leon VIDAL.