Summary of Correlations of Bioclimatic Ultraviolet and Total Solar Radiation in Washington, D. C., 1941–1950

This communication summarizes the results of a ten-year series of uninterrupted daily measurements of the biologically effective component (of wave lengths 2900Å to 3150Å) of ultraviolet solar and sky radiation, incident on a horizontal plane, useful in heliotherapy. Although recent weather conditions were abnormal, the ten-year averages of the monthly totals do not differ markedly from the six-year, and the eight-year averages previously reported in this Bulletin.