Cyclopedia of applied electricity : a general reference work on direct-current generators and motors, storage batteries, electrochemistry, welding, electric wiring, meters, electric lighting, electric railways, power stations, switchboards, power transmission, alternating-current machinery, telegraphy, etc. (1916)
American Technical Society · Chicago : American Technical Society · leaf 426
smay be connected to a battery, or be adapted to use on the mainssupplying the lamps in the room where measurements are to betaken. All stray light is carefully screened from the interior of thebox by a series of screens G. The instrument scale is calibrated infoot candles and in candle-powers.… … Fig. 91. Sectional View of Sharp-Millar Photometer nation is desired, is reflected to the photometric device by the mirrorat //. A second plate K is mounted so as to be illuminated by thestandard lamp and the photometer is balanced by making the illumi-nation of A and K the same. When the intensity…
Electrical engineering
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