The Optical Magic Lantern Journal (April 1899)

2nd March, 1899. Robert Williams Wood. Improvements relating to the production of coloured photographs, and to apparatus for viewing the same. Complete. 2nd March, 1899. James Harding-Lancaster. Acetylene gas lamr;s. 8th March, 1899. Alexander Hughes. Improvements in the construction of binocular glasses. 9th March, 1899. Edward Jame; Dolan. provements in acetylene lamps. Im SPECIFICATIONS PUBLISHED. Copies of the following specifications may be obtained by remitting I/— for each specification to W. P. Thompson dé Co., Patent Agents, 322, High Holborn, London, W.C. 25016 of 1898. Schwass. Acetylene generators. 8054 of 1898. Moores and Farrell. Means for fixing or fitting incandescent electric lamps into lanterns. 2585 of 1898. Barnard. Means for obtaining uniform illuminations in microscopes or similar optical instruments. 9337 of 1898. Clark (the firm of Haas). Process of and apparatus for the production of grained glass plates or screens for photographic purposes. 27821 of 1897. Upward and Dalmer. Apparatus and mechanism for the display of inscriptions, pictures, and the like for the purpose of advertisement. 5037 of 1898. Parson and Bastian. Apparatus for producing vari-coloured effects with illuminated advertisements or the like. 9805 of 1898. Huet. Binoculars, telescopes, and other optical instruments in which it is desired to obtain a rectified image. x x Novice.—In fitting up your lantern in the manner suggested everything depends upon the size and make of the body, but presuming it 1s the average kind fitted for limelight you will scarcely find sufficient room in the lower, but if you happen to have the requisite space you might manage it as there is ventilation at the sides of the division. Used with the illuminant you desire you would have to dispense with a chimney, at least in the lower lantern. As far as the heat is concerned that will not hurt the upper light. Of course you would turn the lantern not in use down to the bye-pass. You will find information on al] subjects pertaining to the lantern in our back numbers. G. H. Phelp.—We have referred to the manusoript of the advertisement and find that we published it correctly in every particular. The advertiser intended letters to be sent to, etc., and yon addressed it to Mr. Letters, etc. Possibly the postman asked for someone of that name. We addressed your envelope and forwarded it with our official stamp upon it’and it has not come back, so we presume you will have heard from the party. H.H.—There is no such box upon the market for lantern alides as that which you enquire about, but this make is used in conjunction with thin disca of much efés and ueries. B nd Y The Optical Magic Lantern Journal and Photographic Enlarger. | explosive mixture. | Opening in pipe without danger so long as there was | employed there, and you may be one. ; even the name of the party of whom you complain. larger size and for quite a different purpose. Some six weeks ago we made 4 rough sketch in our note book of a design like thia taken from the large box we saw, and intended to suggest that it be made for lantern slides. We shall probably call attention to it in next iesue of this Journal, and doubtless several makers will place such upon the market. R.T.—To be candid in the matter, we do not think much of it. We would suggest that you yourself have never tried it practically; it simply will not work, although the theory part is very nice. E. A. Colborne.—Thanks for the cutting, we get that particular paper regularly. We havo heard of the same kind of explosion happening before, although not through such a length of piping. The generator contained an | explosive mixture evidently brought about by filling it with air, the acetylene from the water forming an This would blow through the smal] force behind it, but it appears the force was expended, that is, the bell container was down; the pipes thus contained an explosive mixture which fired back, which, under the circumstances, was to be expected. Photophilus.—(1) To work a triple in the manner you suggest would be impracticable. It would necessitate the expenditure of a great deal of money, and you would require a pantechnicon van at least to cart the accumulators and other apparatus about. For the four lanterns the cost would probably be about £300, and would weigh something like six tons, and if the convenience were at hand for recharging this would cost a few pounds. We think these particulars will be sufficient to explain why your plan would bea impracticable. (2) The lustrous surface is a decided disadvantage. A. J. Morton.—You will find Anderton's silver faced screen preferable. Notlom Htuos.—You do not send your name, hence we cannot publish your letter. True it is written on headed paper, but it does not follow that you are the person whose name is printed at top. Owing to the style of business indicated, it is probable that many hands are You do not give Magnet, F. J. Scrimgeour.—We are sorry we have again ' had to hold your articles over, but have entered them for next. ~N @orr nde CAMBRIDGE SLIDES. To Mr. J. Hay Taylor, Editor. 81n,—Can any of your readers kindly tell me where I can get plain slides of the following buildings at Cambridge :—Downing Colleze, Sydney College, Magdalene College, St. Catherine's College, the University Library, St. Benet’s Church Tower? I have failed to obtain these, as none of them appear to be included in the ordinary sets. Yours faithfully, (REV.) F. E. CAMERON. Bonnington Rectory, Hythe, Kent.