THE death of Hann, which was briefly noted in the issue of NATURE for October 13, removes from the meteorological world the most prominent figure of the past generation and the most productive of all contributors to, that branch of science. Hann was born at Schloss Hans, near Linz, in Austria, on March 23, 1839, and his youth was spent in the Alps at Kirchdorf, in Kremstal, some thirty miles south of Linz. After taking his degree in mathematics and physics, he took up a professional career as teacher of those subjects in the high school of Schottenfeld, Vienna, and afterwards at Linz. At the age of twenty-nine he was appointed on the staff of the Central Anstalt für, Meteorologie at Vienna, which was then under the direction of Carl Jelinek. He succeeded Jelinek as director in 1874, and continued in office until 1897, when, at the age of fifty-eight, he gave up the appointment and retired to Graz, in Styfia, in order to pursue his studies in meteorology; but, finding Graz inconvenient for that purpose, he returned to Vienna in 1900, and thereafter, as professor in the university, he occupied a room in jthe Central Anstalt on the Hohe Warte, and continued to work there until the end of his life.