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Show Varying Strength of Sunlight. There is practically no such thing as Over lighting, writes J. H. Kurlan-der, Kurlan-der, in describing for the General Science Sci-ence Quarterly a series of tests made by the lighting service department of the Etllson lamp works. He adds: "Investigation "In-vestigation of places which are said to lie ovorlighted' will usually show that, if anything, they are glaringly under-lighted." under-lighted." These tests showed that sunlight lu an open field measures 8,000-foot caudle cau-dle power (which means that it gives the illumination that would be given by 8,000 candles a foot distant). Sunlight Sun-light in a street between buildings measures 3,000-foot candles. Shadow-In Shadow-In a street between buildings measures 300: under a tree in the open, 500. The light on an offiee desk next to a south window lias an intensity of 110-foot candles ; one ten feet in, 70, nnd one 18 feet In, 50. At Inside benches between be-tween two exposures only 20. |