Recent determination of the solar constant of radiation

The present volume 1 is an account of the work of the Astrophysical Observatory of the Smithsonian Institution from 1900 to 1907, with details of the investigations made, the apparatus and methods used, and the results obtained. Speaking broadly, the investigation relates to the intensity of the rays of the sun and the dependence of the Earth's temperature thereon. The subject is treated in three parts: First, the amount of the solar radiation as it would be found if measured outside the Earth's atmosphere, at mean solar distance, or, as is often termed, “the solar constant of radiation;” second, the dependence of the Earth's temperature on the amount of solar radiation; third, the difference in brightness between the center and edge of the sun's disk and its relation to the quantity of solar radiation received by the Earth.