Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 79
Fig. 2.—Illumination Data for Oldham Lamp. Area of light in a 6 ft. radius circle, 104*39 sq. ft. Area of shadow in a 6 ft. radius circle, 871 sq. ft. Ratio of shadow to light 1 : 11*987. Fig. 3.—Illumination Data for Hailwood Lamp. Area of Light in a 6 ft. radius circle, 9715 sq. ft. Area of…
Lighting
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