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January 9, 1863.] THE PHOTOGRAPHIC NEWS. 23 INDIA-RUBBER PAPER. RESINIZED PAPER. Dear Sib,—At the beginning of last year, I tried printing on paper, prepared with india-rubber and gutta-percha, but was then unsuccessful, on account, as I since find, of my using too large a proportion of these bodies. 1 have since tried some more experiments with the same substances, and some of them have turned out perfectly suc cessful. I was much surprised to see that so many have been trying india-rubber, as I thought the idea of using it to render the paper waterproof before printing, had not been made public. As in the last number of the PHOTOGRAPMIC News you say that you would be glad to receive practical details on the subject, I thought that your readers would like to know the proportions that I have found to answer best. Procure some pure benzole, and in four ounces of it, dissolve twelve grains more or less, of pure india-rubber. I say more or less, as different samples of india-rubber are very variable, as regards the extent to which they are soluble in benzole. Some of them swell up to an enormous size, and refuse to dissolve at all. After a suitable sample has been procured, and the correct quantity determined, it is best to keep to it. The india-rubber may be dissolved with advantage, in a little chloroform, before adding 'the benzole. When dis solved, allow the solution to stand till perfectly clear, then pour off the top portion with a flat dish. To prepare the paper, immerse in the way I directed for resinizing paper, draw it from the solution, and hang it up by two corners to dry. Great care is requisite to prevent streaks. Dust must be excluded, as far as possible, from the room, as any of it adhering to the paper whilst wet, would cause a kind of comet. When the paper is dry, it will present a beautifully even, and slightly glossy surface. The paper may now be floated on either of the following solutions :— No. 1.—Distilled water 1 ounce Chloride of Ammonium ... 6 or 8 grains No. 2.—Chloride of Ammonium ... 6 or 8 grains Iceland Moss 6 grains Distilled water 1 ounce The moss should be washed in cold water before pouring the boiling water upon it. Or, No. 3.—The waterproof paper may be resinized. The bath I used is 70 grains to the ounce, with } drop of nitric acid. By either of these three formula, charming prints may be produced. The toning and fixing, is performed as usual. A curious fact with regard to resinized paper, has recently come under my notice. I was much astonished to see a batch of prints remain, after fixing, as dark as when they were taken from the printing frames. I was at the time, at the printing establishment of one of our first photographers, and, as several prints printed there, did not lose at all, I was rather vexed that I could assign no reason for it, and to test whether it was to the chemicals used in toning and fixing that it was due, I brought a few prints away with me, and toned and fixed them at home, where they all lost consider ably. I have since discovered the reason of this apparent anomaly, and now save a great deal of time, by not printing much deeper than the finished print is required to be. Upon removal from the printing frame I wash in two changes of distilled, and one of common water, and use a toning bath of acetate of soda and gold, in the proportion of 20 to 1, made at least a week beforehand, and never use cither the toning or fixing bath more than once. From this, it will be seen, that if the print is washed at first in water, containing a chloride, and toned in a comparatively new bath, it will lose to a very serious amount. Should youthink this letter worth inserting, I should be glad if you would do so,—I am, dear sir, yours truly, II. CoorER, Jun. 5, Aberdeen Park, Jan. ‘3rd, 1863. Resinized Paper. Sir,—My object in thus intruding myself to your notice, is to say a few words on the now controverted subject— photographic paper. It is scarcely necessary here to remind your readers of the importance of the printing part of photography, as, thanks to your stirring articles on the subject, photographers have aroused themselves to take better care of this neglected part of the art. We find most, if not all, photographers using albumenized paper in preference to any other, and yet albumen contains sulphur, the dread enemy of photographic prints; so we find in the very foundation of the proof sufficient cause for premature decay. Now, if any one paper at present in existence may bo recommended, it is Mr. H. Cooper’s resinized paper, described in one of your papers. This paper has many excellent points, and surely no better recommendation is neededt han its well- known preservative qualities. I fear to presume too much on your time, or 1 would give you a formula for toning used by mo, with the best results.—I am, sir, yours truly, D. K. Griffith, P9qotographic lotes an (Queries. ■ Ammonia Nitrate Bath. Sir,—Upon looking over the notices to correspondents, in the News of the 2nd instant, one C. P. W. complains of blisters upon albuminized paper, floated upon the nitrate of ammonia bath. I beg to offer the remedy—namely, add a small quantity of alcohol; I use about four ounces in a 60 or 70 ounce bath, which at once causes the silver (as it wre) to amalgamate as required, upon and with the hitherto repellent-surface.—I am, sir, yours obediently, J. J. HoBBrSS. Washino Prints, Sib,—Possibly the following idea has been already considered, but I have not seen it noticed. To every photographer, the washing of the prints is a dull, manual operation, without a gleam of science to .enliven it. To supersede this troublesome process, I think that the air-pump might bo applied, as follows : Place the prints in the receiver of the air-pump, and exhaust the air; this being done, admit water, which will of course imme diately saturate the paper, then empty out the water, and again exhaust the air. Repeat this process, in proportion to the amount of the prints to be washed. The chemicals that dissolve in water will, I think, by this quick process, bo carried completely away ; whether the print will bo damaged, can only be seen on trial. The experiment would require a very slight modification of an air-pump, and I would have tried it, but do not possess such an instrument, nor am I aware,of the existence of one within sixteen miles of my residence. As I do not think that there is a photographer within the same distance, I have no one but you to consult, and trust you will pardon a “tyro " and “ amateur ” in so doing.—Yours truly, G. W. 0. Photography on Canvas. Sir,—In the British Journal, Dec. 15, occurs the following “ On the same occasion M. Disderi announced that he had just been negociating with an American artist, who had found out a means of producing positive pictures on the prepared canvas employed by painters. At M. Delessert’s, and also at Disderi’s, 1 have seen several specimens of this novelty, and must acknowledge that the result is most remarkable’. The painter having only to terminate the sketch traced for him by photography, and being no longer inconvenienced by the nature of the substance he is painting upon, produces a work which has all the merit of photographic accuracy, and which at the same time has given him free scope for his talent.” I have no desire to detract from the merit or originality of the invention ; but I shall feel obliged by your allowing me the privilege of stating, that as long ago as February, 1859, I had made experiments with a view of obtaining the same desidera tum ; and in March of the same year I had succeeded in pro ducing perfect prints upon canvas as ordinarily prepared for the painter in oils, and had shown them to several photo graphers. I hope to have several specimens of my process at the forthcoming Exhibition of the Photographic Society.—I am, sir, your most obedient servant, Jno. T. Lucas, Jun. 3, St. John's Wood Hoad, Regent's Park, Dec, l&th, 1862.