KOVALEVSKY, Sophie, Russian mathe matician and writer: b. Moscow, 15 Jan. 1850; d. Stockholm, 10 Feb. 1891. She wrote much under the name °Sonia?) She received her early education through her father, a general of artillery, then studied mathematics at Heidel berg (1869) after a sham wedding ceremony to legalize her as a college student. She next studied in Berlin (1871-74) under the private tuition of Weierstrass, her sex not being ad mitted to the university. Her thesis (Zur Theorie der partiellen Differentialgleichungen' gained her a degree at Gottingen. Beside her thesis she wrote two no less important pam phlets Weber die Reduktion ciner •Klasse Ahelscher Integrale dritten grades in elliptische Integrale) and (Zusitze und Bemerkungen zu Laplaces Untersuchungen fiber die Gestalt des Saturnringes) (both published in Acta Mathe matics, 1884). She returned to Russia, thence to Paris (1878), and, becoming widowed through her husband's suicide, she went to Berlin (1883). In 1884 she was appointed pro
fessor of the higher analysis at Stockholm. Other works of hers are Weber die Brechung des Lichtes in kristallinischen Mittel' (in Acta Mathematics, 1885) ; Weber den besondern Fall des Problems der Rotation eines schweren Korpers urn cinen festen Punkt) (ib. 1889), for which she received the Bordin prize of the Paris Academy, raised from 3,000 to 5,000 francs for the extraordinary production. In the realm of light literature she wrote such works as 'Der Privatdozent,) a description of German university life; 'Die Schwestern Rajewski,' an account of her own childhood; 'Die Nihilisten' (Vienna 1896), etc. Her sketches from Russian life appear collectively in Literaturnyja sainenija (Saint Petersburg 1893). Consult Jugenderrinnerungen) (Berlin 1896) ; Leffler, Anna, 'Sonja Kovalcvsky' (Stockholm 1892), and the necrology of Mittag Leffler in Acta Mathematics (Vol. XVI).