The Optical Magic Lantern Journal (October 1896)

172 A STARTLING HUMOROUS SLIDE. To the Editor. Srr,—I have to acknowledge the receipt of four letters which you have been good enough to forward to me from readers of this journal, in response to an article by me, which appeared in the September number. The letters in question ask me the price at which I can supply the set of slides described. I am not interested in a commercial way with respect to lantern apparatus or slides, hence have no slides for sale, and as I took a good deal of trouble to get thie particular set I do not intend to issue copies, But I believe I gave explicit instructions as to how the set could be made, and have no intention to enter into any correspondence in connection with same. Correspondents will therefore please take this as an acknowledgment of their letters, and at the same time although I feel flattered at receiving them, I am unable for business reasons to conduct a correspondence on the subject, and can only refer them to the article in question which, I learned from the editor, reached him too late for insertion in his Annual. Yours truly, J. DOUMER. — —__~ CO: rs STW eG LLIN Ore J Soe wee ee ee Beétes and Queries. 0 SOAR? S. F, M.—Unleas we had an opportunity of seeing the lantern microscope, we cannot say where the error (if any) lies. It is probable that you are using it at too long a@range. Try it much nearer to the screen than the distance you speak of and if not then satisfactory, write again. B.W.M.— The aphengoscope will be found very interesting. As you aay you have two lanterns, better get the dovble form, as you can by thia means get better illumination. In this journal for January, 1890 (which can be obtained from our publishers), you will find an artiole devoted to the subject. Alfred Roberts.—If you refer toa note in the September number of this journal you will find particulars respecting coating material for an opaque screen. Messrs. Field & Co.’s screen mentioned in our ' Notes,” gives the best illumination of any we have tried. Charles Haynes writes:—In several shop windows I have seen bottles of fluid put up for the purpose of transferring illustrations printed with printer's ink, the impressions as made from these illustrations are reversed. T have tried all sorts of concoctions but cannot make them anewer, can you render me any assistance in this mattor. I will gladly send you half-a-crown in return if you can oblige me with same. Ans.—lIn the first place no charge whatever is made for assisting readers. Into about a pint of hot water dissolve about a } of an ounce of soap and add 4 ounces of turpentine. Coat the print and a piece of plain paper with this and press in contact. H. A. Holliday.—With the burner you suggest you will, with acetylene gas, obtain as much light as you will with an ordinary spirit jet. There is no smell when properly burned. The heat would be about the same as that from a burner of house gas. John Morgan.— Your letter was received in due course and the enclosure was forwarded to Rev. Partridge of Cornwall, whose letter appears in this issue. F. Jermyn Smith.—In the majority of cases the address of the patent agents only is given, but Messrs. Airs address is, 84, Hatton Garden, London, B.C. O. K.—We regret we cannot single out firms in accordance with your request for us to mention the respective pages in the Annual of the best firm from which you can | purchase the various apparatus required, on the beat terms. We would suggest that you get particulars from the advertisers, and then 1f we can give you an opinion as to the apparatus best suited to your wants, we shall be pleased to do 80, Walter Graville—The cabinet is made by Mr. Shaw, 104, Aston Street, Birmingham. It is also solid by Messrs. Butcher & Son of Blackheath. Geo. Breck (San Francisco.)—We thank you for the marked copy, and shall be pleased to give a description of your firms’ novelties, if you will give us an opportunity. Your Mr. Goodyear called on us some months ago, and we mentioned this to him, but did not receive any particulars. J. B.—(1) Between the back combination of the lens you will find a metal ring, which keeps the lenses apart. If you remove this and put in a thinner one soas to bring the two lenses closer together, you will probably get better definition. If this does not materially improve it, and it ia & cheap lens, sell it and get a better one. (2) The advantage of the larger condenser is, that all the light will pass through a square mat if it happens to be nearly the size of the glass. Draw acircle on paper of the size mentioned, and on this lay a sheet of glass 3} in. square, and you will at once understand our meaning. The large objective is best for oil, or acetylene gas. G.C.G.—(1) The oil is at fault, and although you may have bought it for best, it is not ;—get the very best kerosene and the trouble will disappear, if the wicks are kept in good order. There ia often a difficulty in getting the best oil in villages. (2) Acetylene in preference, either two or three burners (Bray's 0000) placed one behind the other. See advertisement in this journal; the fittings are supplied by the same firm. A few months ago we gave illustrations and particulars such as you appear to require; see the last four or five numbers. Thorn & Hoddle.—We rote your remarks re the date of your first exhibiting your acetylene gas apparatus, but cannot prolong the discussion, as no good would result therefrom. Post Card.-—Get such a condenser that when a slide with a large-sized mat is laid upon it, the corners of the mat are embraced within the circle. You do not say what size disc you want, but at 25 feet distance you will require a lens of 8 inches focus to give a disc 94 feet in diameter. At 12 feet distance the same lena will give a disc of 44 feet. For your purpose we should suggest alens either of 8 or 10 inch focus. Aa economy has to be studied do not get those you name. J.W.S.—If you wish it with jet attached, 1, 2, or 3 are equally good, and if for a detached jet 4 or 6. H.N.—(lt) The jet is certainly an excellent one. (2) Yes, & good and safe one. There was so much bad feeling . displayed, that we decided not to publish the results. After the judges decided, various parties present took exception to the decision. We tender our thanks to numerous correspondents for their very flattering remarks in connection with our ANNUAL AND ALMANAC.