Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 517
diers reached the last stepin safety. 510 THE ILLUMINATING ENGINEER (dec.) BENJAMIN HALF-WATT ACCESSORIES. We are familiar with the data availableon the spacing of reflectors of the E, I.and F type for ordinary tungsten lamps,and it is satisfactory to note that therange of fittings of this type… … Characteribic photometric curve.
Lighting
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