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106 THE PHOTOGRAPHIC NEWS. [FEERUARY 6, 1891. Motes. A favourite and simple light for the enlarging camera, sometimes employed by photographers, consists of two fish-tail gas-flames, one behind the other, and with a diaphragm in front with such an aperture as to help to yield an image of the requisite sharpness. The brilliancy of the light is increased by first passing the gas through a warm chamber which has previously been charged with solid naphthaline. Once Mr. Fred erick Varley had a curious experience in charging common gas with hydrocarbon vapour. He passed the gas through a vessel containing benzole, and the result was that he obtained as much light in a room with a smaller number of burners as he had previously obtained in the same room with a larger number of burners, yet the gas bill for the quarter was higher; the next quarter passed, yet again more gas was consumed than with the larger number of burners. Here, then, was a problem demanding experimental investigation, and by a little research he discovered that common gas is reduced in volume when it comes into contact with benzole vapour. This, although ordinarily objectionable from an economical point of view, is not so for lantern work, in which a small flame of great brilliancy is desirable; in fact, the aforesaid condensation of the gas is then an advantage. We do not know whether reduction of volume takes place when it comes into contact with vapour of naphthaline. The advantage of the adoption of a standard light for certain photographic purposes is well illustrated in the article in another column by Dr. Eder, for by the aid of the amyl-acetate lamp, adopted at the last International Photographic Congress, he has photometrically determined the amount of light necessary to produce an impression with various photographic preparations. Not many of these lamps have yet been made in Paris, we believe, and some what bad accounts have reached us of the way in which they have been constructed; instead of being made with a silver tube for the wick, a nickel-coated brass tube is said to be used, which is attacked by the acid vapours given off by the burning pear oil. The reservoir of the lamp is too small, so that the contents soon disappear when the lamp is in action. This makes it inconvenient to use in the developing room lantern, or for any purpose in which a long period of combustion is desirable. When a properly- made amyl-acetate lamp comes into the market, it probably will not be used with pear oil at all by photographers, should the light paraffin spirit with the trade name of “benzoline” be found to answer the same purpose practically, whatever may be the case theoretically. An undertaking of permanent historical value to photography has just been inaugurated at New York, in the founding of a collection “in which every photographic book and periodical ever published in English, French, German, or any other language, will be accumulated and placed in the Library of Columbia College, which is open from nine o’clock in the morn ing till ten o’clock at night every day in the year, except Sundays and other legal holidays, and to which every responsible person may always have access.” An active worker in this matter is Professor C. F. Chandler, Columbia College, 41, East 49th Street, New York. There was a meeting of indignant show-folk the other day at the Agricultural Hall to protest against the proposed “Movable Dwellings Bill,” which is calculated to interfere with their rights as citizens to a very uncalled-for extent. The Bill owes its origin to Mr. Smith—a name which to Englishmen is so common that it has become necessary to distinguish the par ticular Smith referred to—and, in this instance, the gentleman is known as Mr. Smith of Coalville. He has done good work in bringing the wandering popu lation, represented by our canal folk, under legislative notice; but he has gone a step too far in describing honest show-folk as a dangerous and immoral class of society, and in seeking power not only to register all travelling vans, but to enter such vans between the hours of 6 a.m. and 9 p.m., with a view to overhaul the domestic arrangements of the interior. An Englishman’s house, whether it be on wheels, or more solid foundations, is his castle, and it is only natural that the show people should rise indignant against the implied slur upon their good name. At this meeting, the leader of the opposition, if we may call him so without offence, was Mr. Joe Caddick. Mr. Caddick is not actually a showman, but he owns a van, and we are quite ready to assume that he is guilty of dark deeds therein, and that his doings are often illuminated by a lurid light. He is, in fact, a travel ling photographer, and, like most photographers, would object to the intrusion into his premises of any myrmidon of the law, unless, indeed, he came to have his portrait taken, and paid for it like a man. We sympathise with Mr. Caddick and all his friends. To brand any one class of human beings, who work hard for their living, as dangerous and immoral, is silly and immoral in itself, and Mr. Smith would do well to bottle up his zeal for a better purpose. Many different media have from time to time been advocated for filtering white light for photographic purposes, and rendering it innocuous to the sensitive chemicals employed in the art. Glass naturally stands first, but it is sometimes difficult to get the safe colour required, and its brittleness is always objectionable. Paper stained with aurine is good for a certain time, but its colour quickly fails, like that of so many of the aniline dyes, if it be subjected to exposure to daylight, as it is bound to be if used to protect an ordinary window. Stained gelatine has also been used, and so has in recent times coloured celluloid; but the latter