Volltext Seite (XML)
14 THE PHOTOGRAP AIC NEWS. [January 2, 1891. allow of its being suspended in a tank or other suitable vessel ; each of these frames is covered with a network of wire or other suitable material; the two frames are hinged together at the base so as to open and shut in book form. When closed a simple clasp or any other suitable fastening keeps the two frames closed in position ; the netwrrks being adjusted to the frame in such a manner that they (the two networks) cannot touch each other, but leave a space of about one-eighth of an inch between their entire surfaces, in which space the print to be washed is kept in position, the contacts of the two frames, when the apparatus is closed, preventing the print slipping out of the apparatus, 151. Janimry Uh, 1890.—“A Developing Dish Rocker.” John BoULTBEE Brooks, Great Charles Street, Birmingham, Manufacturer. This specification describes the mechanical details of dish rocking clockwork, actuated by a spring. 511. January llth, 1890.—“Adapting Shutters to Lens Hoods.” John Edward Thornton and Edgar Pickard, St. Mary’s Street, Deansgate, Manchester, Manufacturers. This invention provides improved means for adapting photo graphic shutters to lens mounts or hoods, so that shutters having openings of suitable standard sizes may be readily fitted to lenses of intermediate sizes. In carrying out our invention, we provide rubber bands or packing of suitable sectional form, as hereinafter described, for insertion in the aperture in the back of the photographic shutter. Through the side of the shutter case we fit a screw so that the end thereof may press behind the rubber band. By turn ing the screw inwards or outwards respectively, the diameter of the aperture can be diminished or increased. By making the bands of various thicknesses—for instance, fo" }" R" —an ample range of sizes is obtained, whilst the screw permits of any intermediate adjustment. The rubber band is formed with one edge rounded or bevelled, and the other with a projecting rib thereon. When the band is inserted in the shutter aperture the bevelled or rounded edge of the rubber makes the aperture of “bell mouth ” shape, so that the lens-hood or mount may be easily pushed in, whilst the rib forms a stop which prevents it from going in too far. In order that the band may fit tightly within the aperture, we find it necessary that the thin or rounded edge shall be longer than the thick or ribbed edge, so that the thin edge may have a greater tendency to spring outwards when inserted in the aperture. This we obtain by forming the band in circular or semi-circular flat strips, having the rib on the inner or shorter edge. Such a band, when made of mode rately hard rubber, and sprung edgewise into the aperture, serves the purpose required. By another method we dispense with the rib, and simply use a plain flat band, in which case the requisite stop is formed by using a flat ring or washer of the required size, which is inserted in the aperture before the band. We do not confine ourselves to the use of rubber exclusively, as leather, paper, or any other suitable material may be used. The advantages of the hereinbefore described method of adapting photographic shutters to lenses are that a smaller stock of shutters may be kept on hand, as the various sized lenses may be readily fitted to the standard apertures, instead of having to fit each shutter to a particular size of lens in the usual way ; the user can also adjust the opening to fit his lens tightly. 15,789. October 6th, 1890.—“ Photographic Stands or Holders.” Arnold Rocholl, 68, Skalitzer Strasse, Berlin, Manufacturer. This invention relates to photographic stands which contain a fixed number of photographs, and in which said photographs are made to change their places one after the other by means of a slide. In using this stand, the foremost photograph is pressed out, and glides down into a lower compartment. Upon lowering the slide and lifting it again, another photograph (always the hindmost) is gripped and also transported to the upper com partment, causing the foremost photograph of said upper compartment to slide down into the lower compartment upon its predecessor. Thus the photographs are caused to perform a circuit from the upper to the under compartment and back, until the first photograph is to be seen again. Correspondente. YELLOW LIGHT IN DEVELOPING ROOMS. Sir,—In the editorial article on page 44 of the Year-Book it is stated that the explanation—based upon the superior illuminating power of the yellow rays—of the popular error in favour of red light for dark room work was first published in photographic journalism on Nov. 28th, 1884. On that date will be found an article by Mr. W.H. Harrison, in which the argument is indeed used, but that this was by no means the first time that it was broughs forward is evidenced by the following extracts from articles of mine that had pre viously appeared in the same journal. Jan. 25th, 1884 : “Ruby glass will certainly cut off more of the chemical action of light than yellow glass ; but then, it will cut off at the same time very much mote of the lumi nosity to the eye by means of which we perform the operations of the dark room. To make the comparison usefully, we should, either by repeated screens of yellow, by lowering the source of light, or by some means, at all events, reduce the intensity and the quantity of the yellow light until it reaches the same amount of brightness of illumination to the eye that we have with the ruby light, and then see which has the most chemical effect upon the plate.” May 31st, 1884 (See article on “Coloured v. Non-actinic Light,” in reply to Mr. Lewis Wright) : “ Suppose it to be found that the lower down the spectrum, the less is the photographic action, it would follow as a matter of course that deep crimson, red, or magenta is the proper colour to use in the laboratory. As a fact, however, the red possesses much less illuminating power than the yellow, yellow green, and yellow orange, and the question should rather be, Which part of the spectrum possesses the least effect upon the photographic film in proportion to its illumi nating power ? ” As mentioned in one of those articles, I recognised the value of Mr. Harrison’s support in the position to which I was led when seeking for a working light less injurious to the sight than the ruby then insisted upon, but that gentleman would surely not be pleased to find the editor crediting him with what does not belong to him. W. E. DEBENHANI. THE QUAGGA. Sir,—In your issue of October 31st, received here to-day, you mention the photographing of some quaggas at the Zoolo gical Gardens in 1872. In April, May, and June of that year I was engaged to take a series of negatives of the animals, rep tiles, and birds then in the Gardens for Mr. Fred York ; I believed then, as I do now, that they were some of the finest negatives ever taken in the Gardens. I ran many risks, and one especially with the rhinoceros. I was inside the paddock— to get rid of the railings—when he charged me ; I managed to get clear away with my camera—a very heavy one—without a scratch. For this I was sketched in the Police Nevis. I learnt a great deal concerning this kind of work while I was in the Zoo, and Mr. York gave me great credit for my work. I left England in June, 1872, and have not returned to it since ; I am coming home next year. Mr. York promised me that he would credit me with any honour the pictures received at the Exhibition, but this I never got. I think this must have slipped his memory, as I know he could not, if he tried, be ungrate ful ; I may say I have a very high opinion of him. I have seen in this country many of my pictures shown on the screen, which sent me back to days gone by. Could I have stayed longer I was going to Palestine, but fate sent me here. I have not corresponded with Mr. York for some years ; I hope to see him in the flesh soon. You are mistaken about the quagga. They run wild