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October 15, 1880.] THE PHOTOGRAPHIC NEWS. 493 Uhe Photographic Ulchs, Ortober 1880 215 13 " • * — । uy Mr. •onnson to De aue V° me lact mat alizarine, use a old gentleman arose, and stood for a moment speechless great many dye-stuffs, is not permanent alone, but must and amazed at the strange operation ; at last, regaining his paper arose from the statements made by Dr. Monck- hoven, to the effect that carbon pigments containing alizarine were not permanent. The cause of the fugitive ness in the prints examined by Dr. Monckhoven was shown by Mr. Johnson to be due to the fact that alizarine, like a self-possession, he exclaimed, “I dunno how that’ll turn out, Mr. Smith ; but I’ll think you’ll find that in the first part of that likeness I looked a bit sober, but in the last part I kinder smiled I ” After all, the public, as a rule, at 1 the present time, we fear, have not a much better appre ciation of the process which goes on when their portraits are taken than had this unsophisticated old gentleman. A Photographic Swindle.—Photography is sometimes made to serve ignoble purposes. Not long ago some in genious swindler in Mississippi made photographs of greenbacks, and circulated them in the back countries among the ignorant class of people there, as a new style of check issued by the Government. The modus operandi was to get them discounted ; they then found their way into circulation, and eventually were paid into the local banks. Singular to say, even at the banks the fraud was not de tected, probably because what with passing from hand to hand—and not very clean hands—folding and unfolding, and innumerable enclosures in leather pouches, they had become dirty, greasy, and generally undecipherable as the genuine greenback. However this may be, over 19,000 dollars’ worth was sent to the Treasury for redemption, where, of course, the swindle was soon detected. lieduction of Gid Silver Baths.-German chemists have for some time past been experimenting in the electrolytic separation of silver from nitric solutions, and Herren Fresenius and Bergmann, following up the researches of Luckow, published in 1865, have greatly perfected the be combined with a due proportion of base. Mr. Johnson said in his paper:—“ It is not sufficient merely to precipi tate the alizarine from its alkaline solution by so much alum as is necessary for the purpose, for alizarine is preci pitated by acids, and alum is an acid salt. The lake so produced may be very intense and brilliant, it may be per fectly insoluble in water, but if it be insufficiently charged with base, it is not the true permanent lake, but that sub stance mixed with a quantity of the uncombined colour which will yield to the action of the light. Hence it is not surprising, therefore, to find that certain photographic prints made with alizarine have been found to be fugitive, and so fugitive as to destroy the beauty of the tint and the intensity of the shade of colour.” Alizarine promises once more to be a subject of interest, since a prize has been offered in Germany for the purpose of testing the perma nence of indigo, alizarine, and other aniline colours when exposed to light. I’d have you to know, sir, that it’s against my rules to sit down in the daytime. I'm one of your up-and-doing men. Sit! Not I, indeed. Can’t stop." “ But,” explained the assistant, “ it will be impossible for me to take your like ness unless you sit. It won’t take you long.” By dint of argument and persuasion, the old gentleman became at last convinced of the necessity of sitting, and accordingly took a chair, and prepared himself for, to him, some hocus pocus operation, taking the precaution to enquire if there was any chance of “ them things bustin’?" The Daguerreo- typist assured him there was not the least danger, and proceeded to arrange the camera, at the same time warn ing his customer of the importance of having a free and process. It had been long known that silver can be preci pitated in a compact metallic state from the solution of silver cyanide by means of the electric current, but it is only recently that it has been effected with nitric solutions. Writing in the Zeitschrift fur Analytische Chemie, the expe rimenters state, in accordance with Luckow, that silver can be easily and completely precipitated from nitric solutions, whether neutral, or containing free acid, but that it is dis posed to take a spongy or flocculent form, so that it easily falls off from the electrolode, and cannot be easily weighed. The precipitate assumes this spongy state especially when it has been deposited from a somewhat concentrated solution by the action of a moderately strong current. By using dilute solutions and a weak current, Messrs. Fresenius and Bergmann have succeeded in throw ing down the silver in a compact state, adhering firmly to the electrolode, and capable of being readily weighed. This result, however, was only obtained in presence of free acid. From neutral solutions even a feeble current precipitated the film in a flocculent state. The following proportions are said to be suitable for obtaining the deposit of metallic silver in a compact form : In 200 c.c. of liquid j submitted to an electrolysis there should be from 0-03 to ' 0 04 grammes metallic silver, and three to six free nitric easy expression ; then, exposing the plate the required I time, observed, “ That will do, sir ; I have you now.” The | PHOTOGRAPHY IN AND OUT OF THE STUDIO. A Sronx of the DAaUERREOTYPE Days—A PHOTOGRAPmIC Swindle—Reduction of Old Silver Baths—The Per manence of Alizarine. A Story of the Daguerreotyping Days.—The Daguerreo types exhibited by Mr. Werge at the Fall Mall Exhibition are in strange contrast with the latest development of photography—the gelatine plate. Whether the latter can be pronounced the omega of the art we cannot say, but it is certain that the Daguerreotype is the alpha. When one hears of photographs being taken in the 150th of a second it sounds almost droll to read of an improvement some two-and-thirty years ago, reducing the exposure from ten minutes to five or six! And yet this was considered an achievement. And what curious ideas people had about sun pictures in those days? In an old American photo graphic journal, long since dead and forgotten, we find a comical story illustrative of this. An elderly gentleman called at the studio of a Daguerreotypist in one of the towns in the western part of New York States. Said the old gentleman, “ I would like to get my Daguerreotype taken, and while I go down street to sell the old lady’s apples, you may take it, and put it up in one of your two dollar cases, so when I come back I’ll see how I look. Fix it up, as I’m in a deuce of a hurry.” By this time he had got to the door to leave. “ Sir," said the Daguerreotypist gravely, “ you had better sit now.” “Sit! What for? “COMBINATION" OR OTHERWISE? BY H. P. ROBINSON. Shakespeare says:— “ The sight of means to do 111 deeds Makes ill deeds done I ’’ I fear I have sometimes quite innocently led critics astray by giving them a “sight of the means" of going wrong which they have eagerly appropriated and I have (properly appreciated. I The knowledge that I sometimes make “ combination ” acid, the electrolodes being at a distance from each other of one c.m., and the strength of the current such as to evolve 100 to 150 c.c. detonating gas. It is by no means i unlikely that some process analogous to this could be used in photography for the reduction of old silver baths. The ordinary method of precipitation and reduction by heat is always attended by more or less trouble, and electrolysis is such an elegant process that, could it be used practically, it would have many advantages over the old plan. Of course, there is the question of cost, and here it is possible a drawback might arise. The Permanence of Alizarine.—The paper read by I Mr. J. R. Johnson at the Photographic Society some two years ago on “ Alizarine, its Use in Carbon Printing,” and the somewhat warm discussion which ensued thereon, will be well remembered. Mr. Johnson’s