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March 6, 1891.] THE PHOTOGRAPHIC NEWS. 193 to the use of any particular solvents or proportions, as they have to be varied to suit circumstances. A good proportion, however, for a fluid compound is from four to six parts of solvent to one of solid matter. After the solvents have evaporated, the celluloid is coated in a darkened room with the sensitive gelatino-bromide of silver emulsion ; when this is dry, the back of the paper is moistened with a solvent of the first coating, such as benzol in the case of india-rubber ; the finished film is then separated from the paper support or backing; this may advantageously be effected by connecting the ends of the film and paper to two separate rollers, which, on simultaneous rotary motion being given to them, will act to separate the film from the paper and wind them up respectively thereon. I would here remark that I am aware that a collodion film has been spread on paper whilst the latter has been attached to a sheet of glass, and such film has then been coated with sensitised emu’sion, but in such case the paper has remained attached to the film, and was not separated therefrom until after the negative had been exposed, developed, and fixed. 1 am also aware that paper has been coated with soluble gelatine, which has then received the sensitive emuleion rendered insoluble with chrome alum, and that the back of the paper has been coated with insoluble gelatine to prevent the film curling. In this film the paper has formed part of it until after exposure, development, and fixing, when the film bearing the image is stripped off the paper, which latter carries with it the insoluble gelatine backing. In this case collodion or celluloid is not used. I am also aware that a photographic film has been prepared by first coating paper with insoluble gelatine, then with india-rubber containing grease or wax, then with collodion on which is put a layer of gelitine, and on the latter the sensitive emulsion. Sometimes the pl in gelatine is omitted. When using the above film the paper is not removed until the picture is finished. It has also been proposed to produce photographic films by using a temporary support, such as waxed piper, which is first coated with soluble gelatine, then with algin, which is afterwards rendered insoluble, then with the sensitive emulsion, each coating being dried before the next is applied. In this case the paper backing may be detached from the film at any time by treatment with warm water; but no mention is made of the use of collodion or celluloid in the preparation of this film. Photographic films have also been prepared by spreading a collodion compound upon glass plates, on which, when dry, the sensitive emulsion is applied. I there fore lay no claim to the various methods of forming photographic films above referred to, nor do I claim any of the steps of the process herein described separately considered. What I claim is : A transparent flexible film for photographic purposes composed of a nitro-cellulose compound, with a coating of insensitive gelatine on the one side, and a coating of sensitive gelatine emulsion on the other, made in continuous or long lengths or webs upon a temporary pa; er support, which is removed from the film before use of the latter, substantially as herein described. 5,436. April 10th, 1890.—“ The Exhibition of Photographs.” John Dewk, now residing at the Hotel Metropole, North umberland Avenue, London, Gentleman. This invention is for an improved apparatus for the exhibi tion of photographs or other pictures, by exposing them to a strong light, and throwing on the back certain shades and colours, so as to enhance the perspective and scenic effects, as viewed from the front. It consists— 1. Of a frame adjustable (by hinges or other devices) to any required angle firmly fixed on a substantial stand, in the lower portion of which may be placed a drawer. 2. Of a removable shade which can be attached to the top of the frame, so as to exclude the light, and to give effect to the picture placed in the frame, as viewed from the front. 3. Of sliding panels on each side of the frame, and at the top of the frame, so that the opening can be adjusted to the size of the picture or photograph to be exhibited. 4. Of arms attached to each side of the frame, projecting backwards from the front, and furnished with notches, holes, or rings, for the purpose of holding wires on which can be suspended coloured media or shades ; the arms being capable of elevation and depression, and adjustable to any angle that may be required. 5. Of a metal reflector or frame, on which reflecting surfaces can be placed, hinged on to the lower part of the back of the frame, and adjustable to any angle that may be required, by means of a cord or other mechanical device worked easily from the front of the frame. 6. Of a second metal reflector or frame, on which reflect ing surfaces can be placed, hinged on to the end of the reflector above-described, furthest from the frame, and adjust able to any angle that may be required, by means of a cord or other mechanical device worked easily from the front of the frame. 7. The pictures or photographs to be exhibited should, as a general rule, be made transparent, although this is not in all cases required. They may also receive, in certain cases, a slight colouring at the back, either by paint, or by the attachment thereto of transparent paper, on which the colours could be painted or chromographed. 14,189. September Sth, 1890.—“Films for Use in Photo graphy.” VICTOR Planchon, Boulogne sur Mer, France, Chemical Engineer. My invention relates to films for use in photography, and is designed to afford a support for such films, and thus render the same rigid, and keep them extended during the operations to which they are subjected. According to this invention, I add to the film at any moment in its manufacture thin, rigid, and narrow frames, which form a body with the film when they are finished, and serve not only as supports, but also as extenders. These frames may be rectangular or circular, or they may be of elliptical or any other suitable form, whilst their size varies with the different sizes of apparatus employed in photography. The thickness of these frames can also be varied. They may be quite plane, rounded, slightly stamped at their edges, or partially hollowed or perforated ; they may, if desired, be varnished or coated with any substance which is susceptible of augmenting its adhesion to the film, preventing their oxidation and their chemical action upon the substances which constitute the film, or obviating their alteration in photographic baths. It will be understood that I do not limit myself to any form or size of the said frames, the mode of manufacture employed, the means of applying them to the films, or to the substance of which they are made, which may be of any metal or alloy, or any other rigid substance. The above-described frames are employed in the course of the preparation of the films made by known processes. They are fixed by simple contact, pressure, or by means of an adhe sive substance provided upon or between the layers which consti tute the film. These layers are formed of gelatine, gun-cotton, albumen, glycerine, varnish, fatty substances, or other trans- lucid or transparent substances, modified or not by physical or chemical agents which are sensitive or insensitive to light, these substances being employed alone or mixed with each other. The application of the frames is effected prior to the evapora tion or oxidation of the liquid or syrupy agents employed, such as water, alcohols, ethers, oils, benzine, and any other volatile or siccative liquids, in such a manner that the substances herein before referred to are applied in a humid, swollen, or pitchy state to the sides of the frames, and will cause their intimate adhesion. The frames may be fixed by one of their surfaces, or put between any two successive layers. In practice, the operation may be carried out in the following manner, which, however, I describe only by way of example, as I do not limit myself to the same : Upon any even surface which has been provided with talc, collodion, wax, silicate, or the like, the substances constituting the film are spread by
