The candlepower of a lamp was measu

The candlepower of a lamp was measured by judging by eye the relative brightness of adjacent surfaces, one illuminated only by a standard lamp (or candle) and the other only by the lamp under test. The distance of one of the lamps was adjusted until the two were judged to give equal brightness. The candlepower of the lamp under test could then be calculated from the two distances and the inverse square law.

The candlepower of a lamp was measured by judging by eye the relative brightness of adjacent surfaces, one illuminated only by a standard lamp (or candle) and the other only by the lamp under test. The distance of one of the lamps was adjusted until the two were judged to give equal brightness. The candlepower of the lamp under test could then be calculated from the two distances and the inverse square law.

The candlepower of a lamp was measured by judging by eye the relative brightness of adjacent surfaces one illuminated,, Only by a standard lamp (or candle) and the other only by the lamp under test. The distance of one of the lamps was adjusted. Until the two were judged to give equal brightness.The candlepower of the lamp under test could then be calculated from the two distances and the inverse square law.
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