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May 15, 1891.] THE PHOTOGRAPHIC NEWS. 363 PHOTOGRAPHY IN AUSTRIA. Nature Printing—Aluminium Light—Toluol MATT Varnish. At the meeting of the Photographic Society on the 20th January, 1891, was read a paper on an historical process. It is not, however, a purely photographic subject which is in question, but the discovery known under the name of “ Nature Printing,” but now existing only in the shape of Woodburytype. Some people, doubtless, still remember the melancholy Henry Bradbury, the son of Dicken’s and Thackeray’s publisher of the house of Brad bury and Evans, and himself founder of the firm of Bradbury and Wilkinson, who died in 1860. In 1850, while still a young man, he was a pupil at the State Printing Office in Vienna, just at the time when the dis covery' was made that it is possible to take impressions of leaves on soft lead and then produce images in intaglio from them by means of galvano-plastics. In this way illus trations were made not only of twigs, but of whole plants. Also cut agates and other veined stones were corroded, and impressions of them taken in this same manner. The affinity of this process to Woodburytype is manifest. In England it was patented by Bradbury. The Austrian patent is dated 12th October, 1852, but the process was thrown open to public use. In proud self-consciousness at that time Auer, the father of the discoverer of the net on incandescent gas-burners, said Russia made Jacobi’s use of galvano-plastic free in the year 1837; France, Daguerreotype in 1839. Now Austria has furnished a worthy companion to the two discoveries. But the graphic arts took another direction, and “Nature Printing” was forgotten. Nor was this the first time, for, as Mr. Einsle proved at the January sitting of the Photographic Society, the same process was discovered in 1763. He showed the meeting a book entitled: “Die Nahrungs- Gefaesse in den Blaettern der Baeume nach ihrer unter- schiedlichen Austheilung und Zusammen fuegung sowie solche die Natur selbst bildet, abgedruckt von Johann Michael Seligmann, Kupferstecher in Nuernberg. Nebst Tit. Herrn Hof. Raths Christoph Jacob Treue Historischer Bericht von der Anatomie der Pflanzen und von der Absicht dieses Workes. Nuernberg, gedruckt bey Johann Joseph Fleischmann, 1748.” This book contains coloured illus trations of leaves exactly like those produced by nature printing, except that they appear to be from relief plates, whereas Auer prepared copper plates. We can obtain only one passing hint as to the manner in which the old Nuremberg master went to work, viz., on page 4, where he says “he will print the thus prepared vessels (i.e., the skeleton leaves) themselves .... because it would be impossible to imitate nature perfectly by drawing or copper plate engraving. ” The second preface, which begins to describe the process employed, is imperfect in the copies of the book to be found here. Should any readers of this journal possess a complete copy, it would be interesting to learn from the second preface in what way Seligmann pre pared his plates. Communications on the subject may be addressed to Herr Einsle, Antiquary, Vienna. Aluminium Light.—At the sitting of the Photographic Society on the 3rd March was shown a picture taken by aluminium light. Powdered aluminium, or aluminium waste from the leaf, burns in a spirit of wine flame, although more slowly than magnesium. But with bodies which give off oxygen, or in oxygen itself, it produces an extremely actinic light, and also without smoke, which is its chief advantage. As the experiments are being con tinued, and as the fact that Messrs. F. Probst and Max Putz are conducting them offers a certain guarantee of success, I hope another time to be able to report again. At present we have some very nice specimen pictures taken by it. A New Matt Vanish with Toluol.*—That part of coal-tar which passes over between 100° and 130° centigrade con tains essentially toluol (toluene) besides a little benzene. This is the toluol of commerce. It is not so valuable as benzene, boiling at 110° C.; benzene boils at 8° C. Like benzene, toluol has the property of separating resin from an ether solution of sandarac, but toluol possesses this quality in a higher degree than benzene. In order to obtain a matt varnish from 100 c.m. 3 of an ether solution of sandarac 1 4- 9, an addition of 45-50 c.m. 3 of benzene is necessary. In my experiments, 35 c.m. 3 did not yield any matt varnish ; with 40 c.m. 3 of benzene I obtained films more or less dull. But if one uses toluol with 30-35 c.m. 3 of it to 100 c.m. 3 of solution of sandarac 14-9, one obtains a varnish which dries matt. The following formula repeatedly produced good results in the prepara tion of toluol matt varnish:— Ether 100 c.m.> Sandarac 10 grammes Toluol 35-40 c.m. 3 Put the ether into a little bottle, and add 10 grammes powdered sandarac ; if well shaken, the resin dissolves in a few minutes; then filter the solution through a folded filter, and mix the filtered matter with 35-40 c.m. 3 of toluol. Although one obtains a matt varnish with a smaller quantity of toluol, yet, nevertheless, it is advisable to add 25-40 c.m. 3 of it, as the layers become more equal, and wavy stripes are not so liable to arise. Pour the matt varnish on to the middle of the plate held horizontally; by tipping the plate gradually, one makes the varnish run into the corners, and, finally, run off the surplus at the corner by tipping the plate, not moving the plate on the level till after that. It is important to ob serve this procedure exactly, in order to obtain equal matt layers. It is not advisable to swing the plate at the beginning of the pouring on; it should not be done till the plate is vertical. The beginner requires pretty long practice before he succeeds in covering the plate with matt varnish uniformly. This matt film almost at once takes soft pencil (KI) very well and uniformly, and allows of the most varied retouch ing with stump or colour. The film shows relatively great resistance. The addition of some drops of absolute alcohol influences the formation of grain ; if one adds more than thirty drops of alcohol to the above quantity, the shadows easily become wavy. A strong dilution with ether acts similarly. In the above formula, one may use 120 cm. 3 instead of 100 cm. 3 of ether for dissolving the sandarac, which produces a less covered matt varnish showing a more open grain ; but in its total effect it differs little from concentrated varnish, but it permits less dabbling and rubbing with the damp hand ball. As to the current price of materials : Toluol matt varnish costs less than benzene matt varnish ; 1 Kg benzene puriss. costs (in Austria) 2s. 6d. to 5s.; ordinary benzine, Is. 8d. per kilo gramme. At the same time, in regard to the cost, one must consider that, under the same conditions, less toluol than benzene is required as an addition to the solutions of * From the Pho*offraphische Correspondenz,