Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 125
Fig. 14.—Polar curve of 250 v. 150 w. gas-filled lamp in conjunction with Semi-indirect 14 in. Opal Bowl shown in Fig. 4a(lamp filament 2 in. below plane of top ofbowl). Fig. 15.—Polar curve of 230 v. 150 w. gas-filled lamp in conjunction with Scmi-indircct 14 in. Opal Bowl shown in Fig. \\(lamp…
Lighting
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