The Optical Magic Lantern Journal (April 1897)

74 The Optical Magic Lantern Journal and Photographic Enlarger. (a) by fire-light, (b) by day-light. (c) The shadows of the rod were so different in tint that it was difficult to match them in intensity ; but the result of several trials gave : Acetylene: paraffin: : 1 : 0:88 It was a little difficult to secure the steadiness of the parafiin flame, and one of the trials gave a decidedly better value for it. Comparisons of the naked flames gave nearly the same results. 3. Comparison of the Welsbach with the Pamphengos lamp :—The Welsbach burner was substituted for the acetylene burner in one lantern, and tested against the Pamphengos lamp in the same way. (a) The remarkable whiteness of the Welsbach light was well demonstrated, it also gave a rather more evenly illuminated disc than the paraffin flame. (b) The Welsbach burner, in spite of its inferior intensity, showed up the lantern slide quite as well as the Pamphengos, on account of the pure whiteness of its light. (c) In this case, as in the previous one, the shadows were so very different in tint (paraftin lamp a warm brown, Welsbach a bluish grey) that it was impossible to bring them accurately to the same intensity. The mean results were Paraffin lamp: Welsbach: : 1 : 0°74. The Pamphengos lamp was also tried against another parafiin 4-wick lamp (Stocks’ patent). When both were worked up to their best, there was very little to choose between them ; perhaps the Pamphengos was slightly the whiter flame of the two, The impression left on my mind by the above trials is that acetylene is decidedly the best second-class lantern illuminant yet out, both as to purity and intensity of light. Its safety and manageability are distinct questions, about which I may have something to say later on. (To be continued.) BURNER FOR ACETYLENE GAS. To prevent smoking of the back burner when using acetylene lantern fittings, a simple device has been brought out by R. J. Moss & Co., Abingdon. The burners, instead of being fixed at the end of a pipe are placed at either end of | 4520, a T piece, the gas passing up the stem and striking the cross-piece between the two burners, thus equalising the pressure and obviating all risk of smoking from this cause ; by means of an elbow it can be screwed on to existing lantern fittings. The same firm have also a new pattern of complete lantern fittings, wherein each burner is controlled by a separate tap. It is also fitted with an improved shape reflector which it is claimed gives increased light. THREE-BURNER ACETYLENE FITTING. Messrs. Thorn & Hoddle have introduced a more powerful burner than they have hitherto sold. In the new one the burners are placed side by side in the form shown in cut. We have not yet tried it, but the makers inform us that the new form possesses great advantages over the old 3) PATENT INTELLIGENGE. FREER bbe ee eee EPS ce The following List, relating to current Patent Applications, 1s compiled expressly for the ‘‘ Optical Magic Lantern Journal” by W. P. Thompson & Co., Patent Agents, of 822, High Holborn, London, W.C., to whom all enquiries for further information should be addressed. No. Recent PaTENT APPLICATIONS. 4282. 17th February, 1897. KE. L. Carr. A new or improved portable acetylene gas generator. 18th February, 1897. LL. Southerns. Improvements in the cinematograph, the cinematographic camera and the like. 18th February, 1897. E. Gossartand H. Chevallier. Improvements in or relating to means for producing and burning acetylene. 19th February, 1897. T. R. Fowler. Improvements in and connected with apparatus for the manufacture of acetylene gas. 19th February, 1897. C. Beck and A. C. Edwards. Improvements in apparatus for photographing and exhibiting so-called animated photographs. 22nd February, 1897. E. Barillot and C. C. Leclaire. Improvements in or relating to the storage of acetylene gas. 22nd February, 1897. P. A. M. Lacroix. An improved automatic apparatus for producing acetylene gas. 22nd February, 1897. A.J. Boult. Improvements in or relating to the production of acetylene gas. (E. Melin France.) 28rd February, 1897. F.H. Smith. Anacetylene gas lamp. 4396. 4424, 4488. 4734. 4761. 4781. 4790,