Illumination items: By the lighting and illumination committee: The cost of daylight

The remark is often heard to the effect that daylight costs nothing. This is true outdoors, but obviously it costs considerably to enjoy daylight indoors. One of the writers has discussed this subject elsewhere^∗ quite a number of years ago, with the hope that architects would give attention to this aspect of natural lighting. Inasmuch as no data on the subject have appeared, the writers undertook the task of computing the costs of natural lighting as at present practised and to compare these costs with those of adequate electric lighting.