The Optical Magic Lantern Journal (April 1897)

76 The Optical Magic Lantern Journal and Photographic Enlarger. the generation of such gas must be only in a building detached at least 10 feet at the nearest point from every other building. 2. That suitable valves or devices for controlling the pressure of the gas must be placed inside the detached building, and a cut-off provided between such building and the building supplied with the gas. 3. That in addition to the above, the piping in the building in which the gas is used must be provided with a pipe outlet into the open air controlled by a safety device, s0 arranged as to Jet the gas escape outside the building whenever the pressure of the gas exceeds 4 ounces to the square inch. I am further informed that ‘' the offices agreed not to admit liability for explosion of acetylene gas occurring elsewhere than in the building which is, or the contents of which are, the subject of the insurance.” From the above it is to be observed that the first of the rules would, as it stands, appear to prevent the use of small generators in dwellings for consumption on the premises, and also of lamps constructed with gencrating chambers, of which one at least has been patcnted in this country. Having recently come to the conclusion of the great advantages of this light, I had made arrangements to carry out on a very large scale the adoption of acetylene gas, but was fortunate cnough to countermand the contract beforc being definitely settled, or it would have possibly put upon my hands a useless article. I consider that the majority will agree that these are somewhat stringent rulcs, and I trust that the manufacturers of the generators and carbide will make it their business to try at once and gct them modified, because, after all, is there this danger in its use that one hears so much about, any more than there is in the various modes of usages of other gases? After a lengthened experience, I should emphatically say, No! If one is using a good make of generator, and the same care be taken with the use of acetylene that is required with gases (say) under pressure, that there should be no need of these strenuous rules now put into force. I trust Mr. Editor I am not taking up too much space in my mild growl, but I do think that this is a matter that should be placed on sounder grounds than that already given. Yours truly, LANTERNIST. (We understand that within the past week or two certain insurance companies have agreed to permit of the use, in @ room, ofa small'generator for lantern work.—Ep ] INSURANCE COMPANIES AND ACETYLENE. To the Editor. Dear S1r,—It may interest your readers to know that the insurance companies are climbing down with regard to | acetylene, and that small generators may be used inside insured buildings without infringing insurance rules as formerly. The carbide must be kept in two pound tins, and some other ridiculous restrictions are added; but as these are only provisional rules we expect in a week or two that, given a proper generator and the carbide kept in strong tins or drums, no objections, from an insurance point of view, will be made. The companies very properly refuse to sanction the use of liquid acetylene. Faithfully yours, A. & J. SMITH. 23 & 25, St. Nicholas Street, and 191, Union Street, Aberdeen. March 18th, 1897, ) BIRLA ODD ODD IAD OL DEO D DOR AD LAY BOLD DODD | E3&* Editorial DPable. + 9c! ig TAR RR ER TR R e ARR AS HanppBook To Goruic ARcHITECTURE. — London : Hazell, Watson & Viney, Limited. The author of this work, the Rev. T. Perkins, M.A., has written this book partly with a view to giving certain information respecting the most satisfactory conditions for photographing architectural subjects. In upwards of 200 pages, the author, who is a well-known authority on architecture and archeology, imparts valuable historical information in an easy readable style, which keeps the attention of the reader rivetted to the subject from beginning to end. The book is profusely illustrated with artistic half-tone photographic reproductions. 20: y QE Ce ke | eZ. 9LOVUY Ory _y 1 ; Peles and Queries. ~ OARS ; Constant Reader.—The rule in the past has been double in winter and single in summer. The amount of subscription provides for this. Twopence in future. H. G. Madan.—Thanks for your communications ; they are of great interest. T. I. P. (Trinidad).—(1) It is probable that the arm of microscope carrying the objective has got bent a little out of centre; if this is so the remedy is obvious. ‘The alternating current is not good for micro-projection, having two arcs which are more or less travelling about, and thus it is impossible to keep the light in so small a spt as is necessary with high powers. (2) Weare unable ,; to supply any information about the syndicate ; everything is very much of a secret at present. (3) Since the date of your letter, you would have seen several advertisements and notices re animated photographs in the past few numbers of this journal. J. A. Dizon —Thanks for particulars; see notes, G. H. Philp.—Letter was at once forwarded. To Readers.—In our columns for February, 1893, an announcement was made in connection with the National Lantern Slide Exchange at 20, Parsonage, Westleigh, Leigh, Lancs. Mr. Ch. Kirkham, of 29, Derby-street, Leck, writes to inquire whether it is yet in existence, as he would be glad of information as he sent in a number of slides. Perhaps some of our readers may be able to give some information. we N. R.—The appliance is cheap, and‘we doubt if it is worth repairing. Anyhow, a satisfactory job could not be made of it. ‘“* French” says: ‘‘ I have ruled two glasses for adjusting the discs of my bi-uniallantern, and try how! will I cannot get them fastened in the frames with such trueness as is necessary. How is it done? Ans.—If you take, say, two sensitive lantern plates, and first of all fasten them in the frames, you can, by means of a carpenter’s gauge, scratch the necessary lines on each, using the outer edge of the top and end only. Mark the same lines on both plates before altering the gauge for the next line. One edge from which the measurement was made should rest on the runner, and the other in the stop at end. F, Morgan.—We do not know if the firm is now in existence, but they used to have extensive premises in Sunderland. Have you written to them ?