Measurements of Solar Radiation

Abstract

IT is impossible within the limits of a short notice to give any detailed description of Prof. S. P. Langley's great work, contained in his first volume of the “Annals of the Astrophysical Laboratory of the Smithsonian Institution.” It is an account of his experiments with the bolometer, begun on Mount Whitney in 1881 and continued for eighteen years, first at the Allegheny Observatory and, since 1890, at the Smithsonian Institution at Washington. The volume before us deals with this last period; the results of the earlier period are conS tamed in the Report of the Mount Whitney Expedition, published as one of the professional papers of the U.S. Signal Service Department and elsewhere. Striking as these were, their interest and importance is entirely eclipsed by the new work.