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442 THE PHOTOGRAPHIC NEWS. [July 13, 1883. Patent Entelligence. Application for Letters Patent. 3362. Frank Wirth, of the firm of Wirth and Company, Patent Solicitors, at Frankfort-on-the-Main, in the empire of Germany, for an invention of “ An improved method of producing plates by photography, to he used for printing purposes.”—A com munication from the firm of Benecke and Fischer, of St. Louis, United States of America, and John Frank, a person resident at Frankfort-on-the-Main, in the empire of Germany.—Dated Gth July, 1883. Notice to Proceed. 2799. Joseph Julius Sachs, of Gray’s Inn Road, in the county of Middlesex, for an invention of “ Improvements in appara- ratus to be used in the preparation of metal surfaces for etch ing, engraving, and similar purposes.”—Dated 5th June, 1883. Specification. Published during the Week. 1608. R. H. Brandox, "Gelatino-bromide film paper for photo graphic negatives.”—A communication from A. C. A. Thiebaut. This invention consists in the preparation of a gelatinised bro mide of silver film paper from which the pellicle or film, after the photographic negative has been produced by exposure and deve lopment in the usual manner, is detached or peeled of in a dry state by hand without the assistance of any dissolving or other agent. Since the discovery and use of rapid glasses prepared with gelatine and bromide of silver, constant effoi ts and trials have been made to replace the glass universally used, by a light support, not brittle, as fine and as transparent as glass, and at the same time easily handled for the purpose of obtaining photo graphic negatives. The paper which I have invented for this purpose answers all the requirements of the art, and has the following advantages :— First. The sensitive coating is regular, and its thickness is uniform throughout the entire surface of each sheet. Second. It can be exposed for a luminous impression in any kind of slide as usually constructed. Third. It can be developed and fixed as easily as a negative on glass. Fourth. The negative obtained dries quite flat on blotting- paper. Fifth. The film which constitutes the negative can be de tached or peeled from its support or backing easily and readily by the hand, without the assistance of any dissolving or other agent. Thus this invention does away with all sensitive prepara tions on glass, which latter is both a brittle and relatively heavy material, thus diminishing the bulk and weight of amateur’s and scientific photographer’s luggage when travelling ; it produces photographic negatives as fine and as transparent as those on glass, in so much that the film does not contain any grain ; and, lastly, it admits of printing from either face of the film, as re gards the production of positives on paper or other material, as well as plates for phototypy and photo-engraving, which latter processes require a negative to be reversed. For the manufacture of my sensitised film paper Firstly. A gelatinised sheet of paper is properly damped with cold water, and when evenly saturated it is placed on a glass, to which it is attached by means of bands of paper pasted partially on the glass, and partially on the edges of the said sheet; in this state it is allowed to dry, whereby it is stretched quite flat. Secondly. I coat the dry sheet with a solution of ordinary collodion, containing from one to two per cent, cubic measure of azotic cotton (1} per cent, gives very good results) and from 1} to 2} per cent, of castor oil (2 per cent, gives very good results); this coating is allowed to dry ; and, Thirdly. The glass, with the prepared paper upwards, is levelled, and then it is coated, in a room from which all rays but red rays of light are excluded, with a tepid emulsion of bromide of silver to the extent of about one millimetre thick, and after leaving it in this position until the gelatine has set (say) about five minutes, with the film paper still attached, it is placed upright in a drying room, where it should remain about twelve hours exposed to a temperature of from 62 to 66 degrees Fahrenheit; and Fourthly. The film-paper is detached from the glass ready for exposure, development, and fixing, in the usual manner. For the purpose of developing, oxalate of iron or pyrogallic acid answers equally well; for the purpose of fixing, I have found that a mixture by weight, water 1,000, hyposulphite of soda 150, and powdered alum 60, produces excellent results, after being allowed to dry. Fifthly. The film is peeled off the paper by hand, and can be immediately used for producing negatives recto or verso as above mentioned. I claim as my invention,— Firstly. The preparation or formation of gelatino-bromide film paper for photographic negatives, in the manner and for the purposes above described ; and Secondly. The use for this purpose of castor oil or any other analogous oil, more especially with the view of peeling off the film from the paper backing as above described. WITH THE ECLIPSE EXPEDITIONS. BY C. BAY WOODS. A communication forwarded by way of Tahiti, to which place the Hartford proceeded while we remained on Caroline Island, has, I presume, already been honoured with publica tion, and from it your readers will have obtained, I hope, some idea of how time passed on board an American man- of-war. I cannot refrain from expressing here how deeply we feel indebted to Captain Carpenter, Lieutenant White, and each and all of the officers of the vessel. Every atten tion was paid to our comfort, every help was given us, and after a deal of trouble and labour we found ourselves and our instruments safely situated on a desirable site. We were fortunate in finding two wooden houses surrounded by palm trees, and were not long in taking possession of them and making ourselves as comfortable as circumstances would permit. When the French party joined us, we made up quite a large settlement; Caroline Island certainly never boasted before of such an extensive white population. I need not detail all our troubles and difficulties, the getting up the instruments, &c., but will proceed to describe a spot, insignificant perhaps, yet which may possibly live in history in spite of its small size and remoteness from the civilized world. We knew very little about it a short time since, but now, thanks to our brief stay, no other coral group of the same size has been surveyed and examined with more care and minuteness than this place has been by midshipmen Doyle and Fletcher. It can scarcely be called a group of islands, for it has the main features of an atoll, with this exception, that it is not yet sufficiently raised above the sea level to form an un broken ring. The outside reef is almost unbroken, and the long line of'foaming breakers was in pleasing contrast with the quiet water within. The low islands were thickly wooded, and wherever one went, crowds of birds rose into the air. The lagoon was stocked with fish beautiful beyond description, the shallower portions of it strewn with sea slugs ; at night the sandy shore swarmed with hermit crabs, and crabs that disdained a borrowed retreat fled swiftly at the approach of footsteps. The whole island teemed with life, and the eloquent descriptions of the late Charles Darwin were brought forcibly to our minds at every turn. The brilliant display of colour seemed to challenge the poets’ “ Paradise,” but admiration was tinged with sadness at the thought that no artist was with us to transfer nature to paper and canvas ; memory alone could carry with it a fitting delineation of all that met the eyes. After all, what was photography worth ? Its efforts in black and white fell flat by the side of the living reality, and made one wish for the far-off time when Nature herself shall register her own loveliness by Science’s aid. Not that there were no subjects suitable for the camera. Far from it; but one can always meet with scenes that make dull and ugly photo graphs, but which themselves teem with beauty. But we had little time for taking photographs previous to the eclipse, and even when that was over there was plenty of, work to make pastime scarce. 1 am happy to say, however, that we did not come away without a few mementos of our sojourn. Photographs of the camp of course we obtained, the houses and other objects in the immediate vicinity of the instruments, and the Kanakas dwelling. We let the natives alone, for South Sea Islanders