Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 160
Fig. 13.—Holophane Bowl Refractor.Polar curves showing light distribution from flat ring filament gas-filled lamp andzig-zag filament gas-filled lamp. 150 THE ILLUMINATING ENGINEER (june 1919) Tapped 3^4.Gas Adjusting Screw-Locking All PorcelainGoliath Holder I. Cap
Lighting
Internet Archive · University of Toronto Libraries · Public Domain Mark 1.0. Free to use for anything.
