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It is not necessary to lacquer it. It seems better, to my think ing, to let it alone, just giving it a good brushing to remove the dust, and it may be considered finished. If, however, it gets a single coat of lacquer, the colour becomes blacker, and if there is not sufficient put on to make the surface glisten ; too much lacquer, however, invariably produces an objectionable polished surface. Zotes. The second edition of the “ Photographic Studios of Europe,” enlarged to three hundred pages, will be pub lished to-morrow. Mr. Walter Woodbury has been giving evidence as an expert in several cases of photographic interest in the law courts lately; it would certainly be difficult to find anyone better qualified to act in such a capacity. Yet another knight of science. Dr. C. W. Siemens, who was the last president of the British Association, and whose name is familiar in connection with electricity and applied physics, proceeds to-day to Osborne, in company with Prof. Abel, to receive knighthood. Photographers are, perhaps, not aware that they are constantly having in their hands a cure for drunkenness. An American firm advertises a remedy for this vice, under the name of the “ Double Chloride of Gold.” Professor Pickering, the Director of the Harvard Observatory, has issued an appeal to all possessors of astronomical photographs to contribute duplicate nega tives to the collection of stellar photographs which is now being formed at the Observatory. We were the first among our contemporaries to describe the Swan incandescent lamp, which was not only the earliest practical solution of household lighting by electricity, but is still the most prominent among many rivals. While, at the present day, it would puzzle a purchaser where to buy an Edison, Lane-Fox, or other patent incandescent electric light, the Swan lamps have been for two years past an article of commerce, and, in advertising parlance, are “ sold everywhere.” It was in June, 1880, that we saw the first little shining globule in Mr. Swan’s drawing-room at Gates head, and last week we had the pleasure of witnessing the latest condition of affairs as exemplified in that gentleman’s house at Bromley. Here, with the aid of a half-horse power gas engine, and a series of storage batteries, the lighting of more than a dozen rooms and passages is effected in the most delightful manner. At the door of every room a handy switch suffices to make darkness—in the words of Horace Smith— “ Start into light, And make the lighter start.” On retiring to rest, the gas engine is stopped by the turn of a tap, but the master of the household has still electricity at his command in the storage batteries. He may read com fortably in bed for some hours longer, by a convenient over hanging globe, or, if he so wishes, can suddenly light up any or all of the lamps at a moment's notice. By the way, the removal of Mr. Swan’s bead-quarters to town has given rise to a rumour that be has left his large factory of dry plates and collodion at Newcastle to take care of itself. We may here take the opportunity of denying this rumour, and, strange to say, that although Mr. Swan finds the demand for his gelatine plates still greater than ever the call for collodion does not abate. Ergo, somebody must be working the wet collodion process very energetically still. A simple method of silvering glass is useful to anyone occupied in taking reversed negatives, &c., and the process recently published of M. Palmieri is within the scope of every photographer, especially if he has prepared gelatine plates with ammonio-nitrate of silver. This latter liquid is taken, and to it is added first a little caustic potash, and then some drops of glycerine ; reduction begins at once, and the silver particles are thrown down on the glass, producing a very brilliant metallit deposit. Ether or alcohol added to the mixture accelerates the reduction, and if the photo grapher undertakes the process in his dark room, and employs a moderate heat, there results increased brilliancy in the deposit of silver, and better adherence of the latter to the glass. Speaking of silver deposited chemically, we may call attention to a very interesting fact that has recently been observed by Messrs. Liveing and Dewar. It is that when a deposit of silver particles is made upon a plate of quartz, this is still transparent to certain rays of light; that is to say, that when a spectrum image is permitted to fall upon silvered quartz, a certain portion of the ultra-violet shines through, while the film is quite opaque to the rest of the spectrum. This singular discovery was made by means of photography, which recorded the fact, for the eye failed to appreciate the particular rays in question. Gold particles similarly deposited do not give rise to the same phenomenon, but in support of their theory Messrs. Liveing and Dewar tell us that the late Dr. W. A. Miller made an observation very similar to theirs. He found, namely, that a silver reflector, curiously enough, failed to reflect a band in the ultra-violet spectrum ; in other words, the mirror was transparent to light in respect to these particular rays, although acting as a reflector to all visible rays. Judging from the number of patents which are taken out every year for “improvements” and “inventions” (the latter, by the way, not always synonymous with the former) in connection with photography, Mr. Chamber lain’s Patent Bill, read for the second time on Monday, should prove of some interest to the photographic pro fession. The most important factor in the Bill is that for the payment of £4 (instead of £25, as now) an inventor can obtain protection for four years. Should he at the end of that time discover that his patent is likely to be of mone tary value, he can extend the time to fourteen years by the payment of £150 in two instalments of £50 and £100, the total cost for fourteen years’ protection being £151, or a reduction of £21 on the present fee.