HAGEN, JOHANNES GEORG German astronomer, was born at Bregenz on March 6, 1847. He was educated at Feldkirch, Ditton Hall, Munster and Bonn ; and be came director of Georgetown observatory, Washington, D.C. He left there in 1906. From then on he was director of the observa tory of the Vatican, Rome. His chief work was the study and classification of variable stars. He also examined the dark nebu lae by visual observation, and in 1920 invented the isotomeograph. His publications include : Synopsis of Higher Mathematics, and Aggiunte alle carte dell' Atlas Stellarum variabilium (Rome, 1920).