The Optical Magic Lantern Journal (April 1901)

The Optical Magic Lantern Journal and Photographic Enlarger. 39 Vapour Light for Lanterns. ELATIVE to the description of a vapour light for lanterns, which appeared in our February issue, we have received a communication from the McIntosh Stereopticon Com as) pany, of 35 and 37, Randolph S& Street, Chicago, U.S.A., in which they “2 inform us that they have devised an improved light for lanterns, based somewhat on the same principle as that which we described. This form of illumination they term “The Helios Vapour Lamp.” As we have had no opportunity of seeing or trying this particular lamp, our readers must be content for tle present if we give an illustration of it and quote from the details furnished by the firm mentioned; consequently, it must be kept in mind that in the following details we are not expressing our own opinion :— ‘The Helios Vapour Lamp,” the makers explain, ‘‘ consists of a copper tank, oval in shape, with an iron supporting base, both finished in antique copper. From the side of the tank projects a tube 8 inches long, supporting the burner, which is at the same time the gas generator. Inside the chimney, supported over the burner by a wire, is a special mantle, differing from the well-known Welsbach gas burner only in having an extra heavy coating of the light-giving oxide. The burner tube, alter piercing the side of the tank, is bent downwards so that the open end is near the bottom. In operation the tank is half filled (one and onehalf pints only) with ordinary stove gasoline, by unscrewing the filling plug on top, which also contains the air valve. The space above the gasoline is filled with compressed air, by means of the air pump, in the same manner as a bicycle tyre is inflated. A small amount of alcohol is put into the small brass cup immediately under the chimney, by means of the oil can, ard the alcohol ignited. When entirely consumed the burner is heated sufficiently, so that when the gasoline is allowed to flow into it, by opening the gasoline valve, gas will form and burn, when ignited, the same as ordinary gas, but as the heat of gasoline gas under pressure ard mixed with air is more intense, the mantle emits about three times as much light as when used with common gas at ordinary pressure. One pumping of air is sufficient: for nearly three hours’ use. After once being properly started the lamp needs practically no attention. The mantle having been once ignited is very delicate, and although it can be used for a number of times, if the lamp is carefully put away, without jarring, it will not stand shipment without breaking. The cost of the mantle, although very small, is practically the only expense, as two or three cents worth of gasoline will run the lamp for two hours or more. The mantles, contained in neat cartons, can be carried anywhere before ignition without danger of breakage. Ifthe operator should find at any time the supply of mantles exhausted, he can buy one of any make commonly used and proceed with the.entertainment. No stock of chemicals need be carried, as in the case where acetylene is used, as gasoline can be purchased at almost any grocery or drug store, and as its cost amounts to almost nothing, there is no object in purchasing in quantities. The apparatus {s extremely simple and as safe and easy to operate as an ordinary gasoline stove. The light from the Helios Vapour Lamp stands next to calcium in brilliancy, but cannot be spoken of as a rival except for use in small audience rooms, when its cheapness and convenience will be greatly appreciated by the lecturer and exhibitor.”’ In the above sketch of this vapour lamp it will be noticed that the chimney or hood is of peculiar shape, this is, we understand, the style employed with certain American lanterns of the skeleton type, which have no body but begin with the condenser and end with the objective, but when used with what we in this country consider an ordinary lantern, the upper part of the cowl can be unshipped and the burner attached to an ordinary jet tray. Being particularly desirous of trying a light somewhat of this nature, or to put it in other words, to use a lantern when it was supposed that neither house gas, kerosene, acetylene, oxygen, etc., were obtainable, we, through the kindness