The Optical Magic Lantern Journal (May 1894)

The Optical Magic Lantern Journal and Photographic Enlarger. 103 (6) Reading plain English should not be a difficult task, but it seems to be an accomplishment that falls not to the lot of everyone. That the points here raised should be the result of a deliberate study of the drawings and specifications of my patent does not say much for the perspicuity of the gentlemen concerned. Consequently the value of the opinion of Messrs. Sharp and Hitchmough on the validity of my claims—well, as an American would say, don't amount to much. When Messrs. S. & H. have really discovered that the main and essential feature of my box is the facility with which it can be converted into an open table and slideholder, they are invited to practically teat the validity of the patent by making a copy of the methods used, and we will then proceed to business. Yours truly, W. D. ASKEW. 26, Solon New Road, Clapham, S.W. REGULATING SUPPLY OF GAS TO SATURATORS, Yo the Editor, S1r,—I observe in your reply to some correspondents in reference to Lawson's Saturator, that you recommend them, in order to get a quiet light, to screw up the small valve that will be found under the jet portion. If you had added ‘‘a very little, and with great caution’ it might have no bad result. It is, however, far better and safer to regulate the pressure before it enters the saturutor, and leave that valve always open. If the pressure entering the saturator is too much for the burner to carry off quietly, by damming back the mixed gases at this point you are always liable to have a bang, just as you are liable to have a pop when‘you have excess of oxygen. I have tried it over and over again, and can get bangs and pops at will, but when we know how they are produced they can be more easily avoided. Another reason for regulating the pressure before it is allowed to enter the saturator is that if it is allowed to enter at too high a pressure, and in order to get a quiet light you check its outflow near the jet, you are sure to force ether through several weak points, and have the whole thing ina blaze. Now all these bangs, pops, blazes, are not, perhaps, exactly dangerous, but they are highly unpleasant, and anything likely to produce them should be avoided. J. B.M. SATURATORS. To the Editor, Srz,—I have been very deeply interested in reading the different accounts you have published in your excellent “OpticaL Macic LANTERN JOURNAL "' on Saturators, and, at times, especially after reading my journal, I have been nervous and quite afraid to use my two-cylinder ether saturator, fearing an explosion which would cause a fatal panic to my audience, and perhaps tear open the barrels (as one of your correspondents writes), and spread them like a book. But now at the end of another season, and after four years constant use of the double barrel ether saturator, without a single hitch or failure, I write to say for the encouragement of many timid lanternists who read the “Opticat Macic LanTeRN JOURNAL” that my experience has taught me, that, with a little common-sense care, & double-barrelled saturator is as safe and brilliant as any other lime light illuminant can be. Of course every new patent saturator is the very best and safest. Mine is from the old firm of Messrs. J. Wrench & Son, Gray’s Inn-road, and is as good to-day as when first purchased. If spared till another season, I shall have my saturator tested and new rolls of flannel placed in it, after which L hope to have the same continued success as hitherto, namely, a splendid light with perfect safety. I haveonly used my saiurator with the single lantern. ION. COLOURED TRANSPARENCIES. (A COMPLAINT. ] The following letter has lately been issued by Messrs. Newton & Co.—‘‘It has been brought to our notice that some persons or firms (whose names are at présent unknown tous) have procured plain photographic slides made by us, and bearing our name, as makers, ona label aud after painting them, have replaced the label on them as if they were painted by us; the colouring in most cases being so exceedingly bad asto be calculated to seriously injure our reputation as slide painters. Our objection extends to our labels being left on the slides after they have been painted by other firms under any circumstances whatever, whether they are for sale or painted for customers. We are desirous of cautioning you against purchasing any such coloured slides, and ask you kindly to inform ug if any such cases come under your notice ; as they have increased to such an extent, as to compel us to take the most stringent measures to stop such practices for the future. Yours faithfully, NEWTON & Co.” 3, Fleet-street, Temple Bar, London. :0:——— Notes and Queries. Albert Tranter.—We understand that a transparent black varnish of the style you mention will shortly be introduced. Camera.—It is evident that the camera was not held steady during the exposure, hence the blurred appearance of the negative you sent. The development is all right. T. Gretton writes: I have lately been trying my hand at wet collodion plates, but cannot manage to pour the collodion on the plate without slopping it about. Asit is rather expensive work wasting collodion in practising this part of the work, can you tell me of anything that I can use for practising with that is cheaper, but yet has the same slow flow? I have tried water mixed with several things, but cannot get it to flow in the slow and steady motion of the collodion. Answer.—Try oil. Luz Lanternie (Spain) writes: I am in want ofa receipt for making a black varnish for stopping out skies in lantern negatives. I have tried Soehneis Vernis noir dw Japan and several others, but they crack or peel off. I once had a varnish apparently composed of asphalt, but with what solvent I do not know. How can I make such a varnish? Reply,—Use Brunswick black as a basis, dilute with turpentine, and then add asufficient quantity ofivory black, which lattercan be purchased at any oit shop. W. H. Knight says: Observing that his lantern objective looked somewhat smeary, he took them out to clean them but forgot to notice in what order they were placed in the brass tube, and asks for particulars. Answer.— The front lens, according to your description and sketch,