In 1874 he took part in an expedition untertaken for observing the passage of Venus across the Sun's disk in Kamne-Rybolovo (Far East). In 1876 he was appointed lecturer and later on professor in astronomy at the St. Petersburg University. In 1906 he got the dignity of honorary professor; in 1928 he was elected Honorary Member of the Academy of Scieiices of the USSR.
Since 1876 prof. Glasenapp began taking an active part in popularisation and teaching. I n 1890 he founded the Russian Astronomical Society, of which he was for many years the President. The present development of the meteoric astronomy and the study of variable stars is greatly due to the works of prof. GZasenapp in the end of the last and the beginning of the present centuries. He measured a great number of binary stars in the observatory of the University in the Crimea (Gurzuf), in the Caucasus (Abastuman), and in the village Domkino near Leningrad chiefly with a ginch refractor. His method of determining the orbits of binary stars is well known. For his works prof. GZasenapp was rewarded with the prize of Walz by the French Academy of Sciences.
With the purpose of time determination prof. GZasenapp invented a very portable instrument the ,,sun ring" which was utilised with great success by a great number of amateurs up to the time when the radiosignals were introduced. More than 30 scientific astronomical papers belong to S. P. GZasenapp (he also had works published in the domain of agriculture), besides a series of popular books, manuals of astronomy, different mathematical tables and above IOO separate popular articles and notes.
S. P.
GZasenapp has left a numerous school of disciples; many of them became, later on, professors in universities or distinguished scientific workers. MOSCOW, 1937 Oct.