Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 158
Sff 13 IO 13* SO Fig. 8.—Type I. Street lighting unit showing use of deflector and light distributioncurve when equipped with a 500 watt gas-filled lamp. adjustment to permit proper focussingof the lamp filament, and secure thedefinite form of light distribution eachfitting is designed to give.…
Lighting
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