 A STREET LIGHTCD 1964097 E&MP27.074 Electric Lighting 1/4/41 A street light which turns itself on and off is one of the latest contributions to the illumination art. It is of the sodium vapor type, and has a photoelectric cell, or “electric eye,” built in to the rear of the unit. As soon as the outside brightness drops to a specified level, the lamp is turned on, to be extinguished later when dawn comes. A time delay mechanism prevents a flash of lightning, or an automobile headlight, from turning it off.
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