Westinghouse, Nikola Tesla's employer, manufactured Mazda lamps early in the twentieth century for Bausch & Lomb Balopticons and other magic lanterns. They are interesting lights that seem to have an everlasting nature. This is attested to by some of the pictures and animations below. Furthermore, the following pictures of “Gas-filled Mazda Lamps” offered by the Bausch & Lomb Optical Company in their 1927 catalog should also be of interest—especially to Ebay sellers and buyers as well as magic-lantern historians and collectors. To the two tinted half tone pictures of them found therein, Larry Brian Radka has added some colored photographs and animations of two more Mazda lamps found among his inventory of rusty magic lanterns and carbon arc lights not yet restored to their original condition. The description of the two “Gas-filled Mazda Lamps” included in the Bausch & Lomb catalog runs as follows:
“The new gas-filled shaped Mazda lamps with concentrated filament, which have been especially developed for projection purposes, furnish an automatic, steady-burning and very efficient and economical light source for the simple types of Balopticons.
The efficiency varies from 0.8 watt per candle power in the lower wattages to 0.55 watt per candle power in the high wattages.
They are rated by the manufacturer to have a life of approximately 50 hours and we stand ready to replace any that may prove defective or burn for an unduly short period.
(A Westinghouse 1000 watt Mazda lamp used in a Balopticon manufactured about 1911)
If the Mazda burned only one half its rated life, the cost of operating this type, including renewals, would be much less than the cost of an arc lamp giving equal illumination, when the saving in current and carbon consumption is considered.
(A 500 watt Westinghouse Mazda Magic Lantern lamp still burning after nearly 100 years)
In addition, the Mazda is entirely automatic, noiseless and steady in operation and its efficiency per number of amperes used is higher than that of the A. C. arc.
These lamps are not recommended for microscopical projection as they are not sufficiently concentrated or homogeneous.
Above we see a magic lantern with a 1000 watt Mazda lamp and below a carbon arc microscope projector (micro-projector) with its lenses and lamp house that Larry includes in his collection of antique projectors.
Details on this interesting and rare carbon arc projector will eventually be presented on another Web page.
Meanwhile, here is a picture of the carbon arc electrical specifications on this micro-projector's clock-driven lamp house.
