The photographic news

• Bandzählung: 6.1862
• Erscheinungsdatum: 1862
• 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-id1780948042-186200003
• PURL: http://digital.slub-dresden.de/id1780948042-18620000
• OAI: oai:de:slub-dresden:db:id-1780948042-18620000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Bemerkung: Seite 1-72 fehlen in der Vorlage. Vorlagebedingter Textverlust.
• Strukturtyp: Band

• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

110 Nev’ lit DRAPD Correspondence. FOREIGN SCIENCE. [rnox OUB SPECIAL OOREESPOXDEST.] nal Professo: varsity, " ions onB society, t with a tally ho here wI is ver/, the d” cture 0 morsel 1 1 ' Messtt] se. 1 is, cot nthon’ 1 t on tl‘U ivemep • otogra%A „ by.8 admi" ; April. I Paris, Qth April, 1862. Azroxa the most remarkable photographic productions that will figure in your approaching universal exhibition, are some pictures of very large dimensions, representing views in Egypt, taken by M. Camillas. Specimens were exhibited at the last meeting of our Photographic Society, and excited much admiration. Herr Pretsch also presented some new proofs of heliographic engraving in relief, obtained by the process he published in 1854, in France and in England. •Ie insisted that his proofs were not retouched, although the ftistence of a grain over the plate might, at first sight, render this hypothesis possible. M. Gerard remarked, that having recently had occasion to examine Herr Pretsch’s process of engraving, he found in the description given by the inventor, an indication which lias possibly not been sufficiently remarked upon, but which Would doubtless furnish an explanation of the cause of the general grain in the plates, and consequently exculpate Herr Pretsch from the charge of retouching. M. Gerard stated that, after having caused chromatised gelatine to be soaked in water, and before taking in relief the impression thus produced, he washed it with alcohol ; and it is probably owing to the superficial contraction which is exercised by the alcohol, and a general cracking of the whole surface that ensues, that the effects of grain remarked upon the Proofs of M. Pretsch are due. M. Regnault, the president of our photographic society, has made an appeal to the generosity of those who are in possession of proofs which may possess an historic interest m the art of photography. The society already possesses specimens of the first efforts of Daguerre, Talbot, Bayard, Niepce de Saint Victor, Taupenot, and others. A collection of all these works must necessarily possess the deepest in- terest, and the president thinks that all who have it in their power to enrich it will take pleasure in so doing. Among the more recent contributions to the collection are some posi tives obtained by the last carbon printing process of M. Roitevin, presented byM. Vidal, of Marseilles; and a posi tive and a negative upon albumen, obtained in the earliest gizs of M. Niepce de Saint Victor’s albumen process on m, used’ res so tr of prod as there” ines, th io subje 'or fort M. Balsamo, of Lucca, has made a communication on the subject of his phosphorus process, ho says: "I have only just seen Dr. Schnauss’s remarks in the iifonitcur on my phosphorus process. The proofs I have obtained arc perhaps not first-rate, for want of good negatives and suitable appa- ratus, but they sufficiently demonstrate the facts announced in my Memoirc. Instead of attributing the ill-success of my experiments to charlatanism, Dr. Schnauss had better seek the cause in some peculiarity which has escaped his notice. He is wrong when suggesting the application of heat; by "arming the sensitized paper a chemical action is produced directly opposed to photogenic action. To make sure of obtaining an image upon the paper saturated with the phospho-hydrochloric-cupric solution, it must be left to dry r w, spontaneously at the ordinary temperature. I beg, there- blju” fore, that Dr. Schnauss will repeat his experiments without pd exposing the paper to the action of heat, for solar heat •offices to remove all sensitiveness from the paper. He will then see that my theoretical explanations have a practical value, and that the word charlatanism exists neither in my dictionary nor in that of urbanity. Ho will render me justice, and I shall then pursue photo-chemical phenomena hopefully. I can tell him that I have not only obtained the solution of phosphorus, which he regards as a new pheno menon, but also the black modification of it by an electric polarization of the phosphorus in hydrochloric acid. Our society is not indifferent to the result of the action I than i those J develop raittrfj lit, witl cd wit 11 it with! the same ne and 1 1 ; the 9. c second mt. TV pictur n his cl ar and V to the s ould re" Io alwa la Fotbg but the o addeds dthed® picture 1 iss‛ vie* as very? ng dis® ised all’ ecomn‛ rsh eti ; for tbef 11,180 April 11, 1862.] THE PHOTOGRAPHIC NEWS. 179 for piracy, in which Messrs. Mayer and Pierson were cast, as it involves a question of the deepest interest to photographic property. A committee is now engaged in the examining what measures it may be advisable to take, and to place the matter before the Commission appointed for the preparation of a law upon literary and artistic property. Messrs. Gilles, freres, have recently constructed what may justly be termed a universal camera. The focus ranges from } inch to 70 inches ; it enables the operator to take pictures of every size, from the carte de visite to half life size, with objectives from J inch focus to 6 inches. M. Adolphe Martin has made an important communica tion on sulphate of iron developing solution, which will doubtless remove any objections that may now exist for this substitute for pyrogallic acid; and M. the Abbe Laborde, has replied to the objections raised against his theory of the action of iodine in the sensitizing silver bath ; he has also made a communication respecting the washing of proofs in the linseed oil process, which may have the effect of render ing that process practicable. Some cannon have recently been cast in Austria, composed of a new alloy which is said to be more tenacious than the best iron; it is composed of 600 parts of copper, 382 of zinc, and 18 of iron; it is easily forged and bored, and while cold will bend without breaking. Another alloy, as a substitute for silver, is proposed by M. Trabuc, of Nisines; it consists of banca tin 375 parts, nickel 55, regulus of antimony 50, bismuth 20. One-third of the tin is placed at the bottom of a crucible of suitable dimensions, together with the nickel, antimony, and bismuth ; upon this first layer a second third of the tin is deposited and covered with charcoal to the depth of 1}-inches; the crucible being covered up, it is heated to a white heat, then with the aid of a iron rod, also heated, we ascertain if the nickel be melted and the anti mony be reduced, in that case the remaining portion of tin is passed through the charcoal, and the whole stirred until a perfect mixture of the different metals is obtained, it is then cast into ingots or other forms. The colour of this alloy is silver white, and it resists the action of vinegar and other vegetable acids. PAINTING LANTERN SLIDES—GLASS GUIDES —ROSS LENSES. Sir,—A friend of mine, who painted some slides for me, us?d the usual oil tbe colours, which he pressed out of the tubes on to a little clean blotting paper, in order to absorb the superfluous oil, and then mixed the various tints with a medium composed of about equal parts of copal varnish and turpentine. The glass, I believe, was formerly prepared by pouring over a very thin solution of Canada balsam and turpentine. There is, I believe, a young man residing in Cheltenham who colours magic lantern slides. I have lately cut out some glass guides from thick ground glass, and they have the advantage of not slipping about like the polished glass, and yet are sufficiently transparent to allow one to see where to put them on the carte de visite stereo slide, &c. My glass room being very short I have been using Ross’s new stereo lenses for carte de visite portraits, using diaphragm No. 5, they fill out so well, and give so sharp a picture, that I am induced to recommend others who have those lenses to give them a trial for that purpose ; eight to fifteen seconds is generally sufficient exposure. I enclose two prints from negatives taken with these lenses. The vase and stand I have copied from Messrs. Bull’s work, best made, the high lights much darker than the originals, and now they seem to me to be too light.—Yours truly, Thomas Gulliver. 17, Ileathfield Street, Swansea. [The pictures are exceedingly well covered for a lens of such short focus, and which, it should be borne in mind, was never intended by the maker for such work. ’Where the glass room will permit, we recommend the use of lenses of much longer focus.—Ed.]