Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 39
NG ENGINEEB, often considerably aliead of tliat ofinstallations, which it replaces, so thatthe adoption of the indirect lightingsystem in numbers of cases actuallyreduces the energy consumed. Wemight here summarize the results of atest by Mr. J. R. Cravath on the light-ing of a small room… … Fig. 1(1—Indirect Lighting iu large office,entire freedom from glare. in lumens effective per lumens gene-rated :— Per cent. Direct lighting witli prismatic re-flectors on ceiling , . . . 52Bare lamp at ceiling . . . . 40-9Direct diffused ligliting w ith S in. opal bowl at ceiling.. .. 33-7…
Lighting
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