The photographic news

• Bandzählung: 35.1891
• Erscheinungsdatum: 1891
• Sprache: Englisch
• Signatur: F 135
• Vorlage: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: SLUB Dresden
• Rechtehinweis: Public Domain Mark 1.0
• URN: urn:nbn:de:bsz:14-db-id1780948042-189100009
• PURL: http://digital.slub-dresden.de/id1780948042-18910000
• OAI: oai:de:slub-dresden:db:id-1780948042-18910000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

ALUMINIUM AS A SUBSTITUTE FOR MAGNESIUM. It has been claimed by scientists for some time past that aluminium in minute particles burns in the air, and gene rates an intense light equal to magnesium. At a late meeting of the Photographic Society of Vienna, Herr Patz presented a number of experiments showing that magnesium may be replaced for photographic purposes by the far less costly aluminium. His results were as follows:— Aluminium leaf ignites readily, is not dangerous, and burns with jets of sparks (scintillation). Coarse aluminium powder failed to give satisfactory results. Fine aluminium powder mixed with chlorate of potash and sulphide of antimony gives good results, but generates smoke equal to the magnesium compounds. However, if the sulphide of antimony is dispensed with, this objection able feature is overcome [?—Ed. Wochenllati]. Powdered aluminium blown or thrown through a flame will not ignite. These general results obtained were similar to those arrived at in a course of experiments undertaken several months previous in Berlin by the staff of the PhotoyraphiscJies 'WochenUatl— presumably by Dr. Miethe in person. For this purpose fine aluminium filings and aluminium bronze powder was used, the latter such as is sold on the market as a substitute for silver bronze. Aluminium filings, on being forced through a Bunsen •flame, failed to ignite ; but, combined with some of the various substances containing oxygen (chlorate of potas sium, nitrate of potassium, manganate of potassium), ignited in the usual manner, but the whole mass failed to consume entirely. If anhydrous glycerine is dropped upon a mixture of manganate of potassium and aluminium powder, the compound frequently ignites and burns with a not very strong light, while a magnesium compound under similar conditions would explode with an intense light action. Aluminium bronze powder— which, by the way, is con siderably dearer than magnesium—may be blown through a Bunsen flame, and the combustion will be almost com plete, provided the flame is sufficiently large, and the propelling air properly separates the particles. The chemical action of the light was active, and the resulting smoke hardly noticeable. The same powder mixed with finely-ground chlorate of potassium, with or without sulphide of antimony, burned a little slow, and without giving forth any strong light. On the contrary, if com bined with manganate of potassium, the mixture burned quickly and gave a bright illumination. But even the latter mixture does not always ignite with absolute certainty when treated with a drop of anhydrous glycerine, and, in case, even in small quantities, an ignition docs take place, it is invariably accompanied by a loud detonation.—Amer. Jour, of Photo. The Scientific American points out that, by heating resin with sulphur to about 250° C., a reaction takes place, attended by the evolution of sulphuretted hydrogen, and leading to the formation of an almost black, pitchy substance containing sul phur, and resembling Syrian asphalt in many of its properties. Thus, it is insoluble in alcohol, but dissolves readily in chloro form and benzene, and is sensitive to light in the same way as Syrian asphalt, for which it can be substituted for photographic purposes. patent Intellgence. Applications for Letters Patent. 16,936. Thomas ERNEST Smith, Sandringham House, Osborne Road, Southsea, “A Double Action Instantaneous Shutter for Detective Hand-Camera. October Sth. 17,143. Arthur Brin, 53, Chancery Lane, London, “ Im provements in Photography and in Photographic Apparatus.” —October 8th. Specifications Published. 6,825. May 3rd, 1890.—“Indicator.” J. Parkinson, South Regent Street ; S. Fawcett, Elm House, Meeting House Lane ; and C. F. Parkinson, South Regent Street, all in Lancaster. In roller slides the measuring roller is provided with a pinion which actuates directly, or through a train of wheels, a numbered registering wheel. The pinion may have only a single tooth, or it may have several teeth, the number of which is not exactly divisible into that of the wheel, in which case the indi cator is suitably graduated. (Patent opposed. Case not yet decided.) 7,010. May 6th, 1890. — “Instantaneous Cameras, &e.” B. J. B. Mills, 23, Southampton Buildings, Middlesex. (L. Lumiere, 21, Rue Saint Victor, Lyon-Montplaiser, France.) The camera is provided with an opening at the back for the insertion of the plates. These are enclosed in sheaths, which consist of metal plates with turned-in flanges on three sides, and with trunnions. The trunnions are placed in guides. When all the plates are inserted in the camera, the back, which is provided with a spring to push the plates forward, is closed and secured. The trunnions of the front sheath engage in notches in discs mounted on a spindle, which is worked by a thumb-wheel on the outside, and other trunnions abut against prolongations from vertical guides. The front plate, when in this position, is exposed, and to prevent accidental exposure the shutter may be so connected with the disc that it will be fas tened until the trunnions enter the notches on the disc. To change the plates, the disc is further rotated, thus per mitting the plate to slide down the guide and allowing the next to come into position for exposure. The next, on being released, causes the first to swing and fall flat on the bottom of the camera. The fall is broken by springs at the sides, which springs also serve to retain the plates to the bottom. Received.—From Mr. E. G. Wood, “Magic Lanterns: How Made and How Used,” by A. A. Wood, F.C.S. This, the fourth edition of a useful book of 136 pages, illustrated, has been revised, with additions. From Messrs. Iliffe and Sons, “ Photography applied to the Microscope,” by F. W. Mills, with a chapter on “Mounting Objects,” by T. Charters White. The author explains that his object has been to supply a practical guide to instruct microscopists in the application of photography to their science, and at the same time acknowledges his indebtedness to Mr. T. Charters White and V. A. Corbould for assistance. From the same publishers we receive “ Photographic Pastimes,” by Hermann Schnauss (translated from the second German edition). As we remarked in reviewing the German edition, the matter of the work is much more interesting and instructive than its title might lead one to suppose. The first chapter relates to photographing specialities ; the second, curiosities ; the third, photographing by means of peculiar arrangements ; the fourth, photographic optical entertainments ; and the fifth, entertainments with photographic prints. The book is plentifully illustrated. Funny Folks for Sept. 17 ch, to hand, contains the first illus tration of the “ Comic Camera,” an amusing feature to be introduced into its pages. The subject alluded to is entitled “ Buffalo Bill in the Back Garden ; an Improvised Wild West Scene.” As will be noted elsewhere, our contemporary invites contributions of humorous photographs.