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366 THE PHOTOGRAPHIC NEWS. [June 8, 1883. work—the new ones being used for ordinary line work, and the older for delicate line and chalk work. A hard new roller will take off ink rather than give it, and should, therefore, be kept for subjects likely to clog up. The same roller when older will answer for chalk work, in which it is not a question of laying a tint on the stone, but rather of establishing a contact between the different points of the drawing on the stone and the ink covering the roller. As soon as the roller is old and saturated with ink, so that it cannot take up the excess of ink from the drawing, it is only fit for pen-work, where its action is confined to colouring the lines of the drawing uniformly, without dirtying them or blocking them up. A soft roller, made with two (or at most three) folds of flannel, should.be kept for delicate pen-work as long as the skin retains its property of attracting ink. When it has become smooth it may be used for worn-out stones or common work, or as a cleaning roller in printing engraved stones. It should be borne in mind that the less tendency the roller has to part with its ink the greater will be the purity and brilliancy of the impressions. Care should be taken to keep rollers clean, and ink must never be allowed to dry on them, being removed at the end of the day’s work by scraping with a blunt knife, resting one end of the roller on a table, and scraping upwards from below. Colour rollers should be washed in turpentine every evening; when in use, they must not be scraped. Before rollers are put away for any time, they should be rubbed over with tallow, which is removed again, before the roller is used, by scraping, and washing with turpentine. As the preparation of a roller takes some time, it is sometimes convenient to buy those sold as in use or work ing order, but in doing this caution must be exercised, as such rollers may be, on the one hand, new rollers merely rolled up in black ink, or, on the other, old rollers of which the skins are worn and thin in parts, and hard with dried ink, or else so sodden with ink and varnish that they have lost all grain, elasticity, and power of picking up ink from the stone. We have been rather full in these remarks about rollers, because the whole success of the printing operations is chiefly dependent upon their good quality and manage ment. With careful rolling-in a skilled printer may work up a passable result from a poor transfer, while by bad management the most perfect transfer may be irremediably ruined. Within the last few years, rollers made of india-rubber have been introduced for lithographic printing. These rollers, known in the trade as “ Lanham’s Patent Victory Roller,” are of the same form as the usual hand rollers, but, in place of the flannel and skin, there is a coating about a quarter-of-an-inch thick of soft red vulcanised india-rubber, worked on a lathe to a true surface. These rollers are always ready for use, and are easily cleaned with turpentine. We have found them particularly well adapted for zinc printing, and they are also useful in print ing collotypes. They have, however, the defect of losing their grain, and becoming too smooth and glossy, so that they do not feed the ink well. Ink.—The black ink used for lithographic and zinco- graphic printing is a mixture of fine lampblack, with varnish made by heating linseed oil till it burns. This varnish is prepared of various consistencies—thin, middle, and strong—according to the length of time the burning has been allowed to continue. The ink as sold is mixed and ground by machinery, and is put up in tins in the form of a very stiff paste. It is of different qualities, ranging in price from 14s. to 4s. a pound. The best is the French chalk ink, made of the stiffest varnish and finest black—it is used for first-class chalk work. For most purposes of the photo-lithographer, the medium qualities of stiff and fine inks, from 10s. to 6s. a pound, are well suited. Before the ink as purchased can be used for printing, it requires further reducing with varnish, the consistence and quality of which will vary according as the nature of the work requires a stiff or soft ink. For chalk or other high- class delicate work, strong varnish is generally used ; for all ordinary purposes, middle or thin ; and for colour-work and tinting, thin alone. A small quantity of the ink is taken out of the tin with a strong knife (not a palette knife), and, a little varnish being added, is worked upon the inking slab with a palette knife, thoroughly incorporating the two together, and adding varnish, if necessary, till a homogenous mixture is formed, which should just run slowly off the knife when held in an inclined position. The mixed ink is generally placed at one corner of the slab, on the side away from the printer. (To he Continued.) Oorrespondence. THE NEXT SOIREE OF THE PHOTOGRAPHIC SOCIETY. Sir,—On the occasion of the next soiree, in October, might I suggest that, in order to create a little diversion, and to infuse some life into the meeting, a space might be left, so as to enable the—shall I say more frivolous?— visitors, of both sexes, to enjoy a little dancing? The hire of a piano would be a mere trifle, and both pianists and violinists could easily be got from among the members’ families. Discussions on art, and on the respective merits of dry plates and collodion, are doubtless extremely important; but I fear that some—of the ladies, at least—do not take that engrossing interest in these matters which they should, and therefore it is that, in deference to them, I make the above suggestion. The centre table is always occupied with apparatus, &c., which are of little interest to the majority of the visitors, and which can, moreover, be better studied in the day time. Unfortunately, the day selected for the soiree has hitherto been Saturday. I do not see why the day should not be either the Friday preceding, or the Monday following. But, at all events, whether the day is altered or not, I hope some alteration will be made in the dreary nature of the meeting. If some leading member of the Society would take the initiative, and form a committee of (say) six, who might act as stewards on the occasion, it could be easily managed, and would be certain to prove a success. —Your obedient servant, A. %. FIRE INSURANCE.—READY-SENSITIZED PAPER. Dear Sir,—Your remarks on fire insurance, some time since, when you called attention to the diminution of risk where collodion is no longer used, have saved me nine shillings this year, for on receiving notice from the Company’s agent that my premium was due, instead of sending him a guinea as usual, I wrote a note informing him of the change in my working, and declining to renew the insurance at the high rate charged, and in a few days received a reply offering to take the risk at 12s. In your article on the use of ready-sensitized paper, you speak of the acetate bath requiring a few days to ripen ; but if the acetate of soda and the gold are boiled for a minute in about an ounce of water to each grain of gold, and then diluted with ten ounces of cold water to each grain, it can be used at once ; also, after the dilution, we like the addition of five drops of a saturated solution of washing soda to each grain of gold, as it gives cooler half-tones, while the shadows remain warm. We make a