Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 97
and this cell, as thedaylight faded, acted as a relay and turnedon the lamp automatically. A goodileal had been done in recent years withselenium, and different material- sensitiveto light, and something of that sortmight be done. If the day graduallybecame dark in the middle of the day.and the… … CEHlfiAL HALL PELHAM ROAD SCHOOLS WIMBLEDON- HORIZONTAL OAYLIOHT ILLUMINATIONON DESKS IN FOOT-CANDLES THE ILLUMINATING ENGINEER (feb.) 83 but if the daylight went up to 5 or 6foot-candles some means would have to beprovided for turning down the artificiallight. With regard to the eye rejectingmore…
Lighting
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![An illustration from Catalogue des monuments et inscriptions de l'Égypte antique / publié sous les auspices de S.A. Abbas II Helmi par la direction générale du Service des antiquités [de l'Égypte] ; par J. de Morgan, U. Bouriant, G. Legrain, G. Jéquier, A. Barsanti (1894)](https://img.insideoutlibrary.com/img/200/ia-cataloguedesmonu21egyp-333-646.webp)
