"ELECTRIC EYE"E&MP 94.017 Photo Electric Cells no date Thomas H. Long, engineer of the Westinghouse Electric and Manufacturing Company, adjusts the light sensitive cell known as the "electric eye", so that it will turn on an air beacon just before sunset and turn it off just after sunrise. A pair of these "eyes" are to be put in trial installations near Pittsburgh so that the operation of the beacons will be controlled by degree of light and darkness, rather than by the flexible clock system which makes no distinction between fair and cloudy days. PHOTO 198889 Original Caption by Science Service |
