Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 172
jectionwork—on a new principle of surfacesource of light in place of a point source of bght. Passing reference canalso only be made to the use renderedpossible by the high efficiency of the newlamp of special glass bulbs to give thequality of light required for (a) photo-graphic work (photographic… … Fig. 41.—Floodlight projector for gas-filledlamp. DISCUSSION Mr. Haydn T. Harrison con-gratulated the author on his paper, andalso on using the term Gas-filled Lamps, because they were still oftendescribed as half-watt, an expressionwhich was apt to be misleading,-especiallyas the actual watts pel…
Lighting
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