Friedrich Georg Wilhelm Von, a Russian astronomer, born in Altona, April 15, 1793, died in St. Petersburg, Nov. 23, 1864. He was educated at Dorpat, and in November, 1813, was appointed extraordinary professor of mathematics and astronomy there, two years later becoming ordinary professor. His duty in that office was not only to attend to the observatory, but also to lecture on astronomy and mathematics; but in 1822 the two offices were separated, and Struve was henceforth free to work exclusively as an astronomer. In 1839 he was made director of the observatory of Pulkova, which had been built under his direction, and not long after he was made councillor of state. He confined his labors as an astronomer principally to the observation of fixed and double stars, and made large additions to the knowledge of these bodies. He also conducted the triangulation of Livonia,* and measured the degrees of latitude in the Baltic provinces, and an arc of the meridian between Norway and southern Russia. In 1857 Struve visited England to organize and arrange the measurement of an arc of parallel through the entire breadth of Europe, from Orsk at the foot of the Ural mountains to Valentia at the western extremity of Ireland. This work he fairly initiated, but in 1858 he was attacked by a malady which prevented him from cooperating further in it save by advice and calculation; and in December, 1861, he was compelled to resign his active duties as director of the observatory.
His most important works are: Observationes Dorpatenses (8 vols., Dorpat, 1817-39); Catalogus Norus Stellarum Duplicium (1827); Stellarum Duplicium Mensurae Micrometricae (St. Petersburg, 1827); Description de V observation as-tronomique central de Russie (1845, with 36 plates); Etudes d'astronomie stellaire sur la voie lactee et la distance des etoiles fixes (1847); and Stellarum Fixarum imprimis Duplicium et Multiplicium Positiones Mediae pro Epocha 1830, etc. (fol., 1852). - See a memoir by Prof. Cleveland Abbe, in the appendix to the report for 1869 of the secretary of the Smithsonian institution.
Otto Wilhelm, son of the preceding, born at Dorpat, May 7, 1819. He became his father's assistant at Pulkova in 1839, and succeeded him as director in 1862. From 1847 to 1862, as consulting astronomer, he had the oversight of all investigations conducted by the Russian army and navy. His labors relate chiefly to nebulae, double stars, faint satellites, and comets, and include a new determination of the constant of precession, the discovery of about 500 new double stars and of a satellite of Uranus, the determination of the mass of Neptune, investigations in regard to Saturn and his rings and to the parallax of various fixed stars, and observations of the nebula of Orion. He first showed that the red prominences visible in a total solar eclipse belong to the sun's surface. Besides numerous papers in the Memoires of the academy of St. Petersburg, he has published Uebersicht der Thatigkeit der Nikolai-Hauptsternwarte wahrend der ersten 25 Jahre ihres Bestehens (St. Petersburg, 1865).
Georg Adam, a German jurist, born in Magdeburg, Sept. 26, 1619, died in Jena, Dec. 15, 1692. He studied law at Jena and Helmstedt, and in 1646 was appointed professor of law at Jena, and in 1648 assessor to the high court of the circle of Saxony. In 1667 he was appointed privy councillor to the duke of Weimar, and was selected as his advocate in the case of the succession to the duchy of Saxe-Altenburg. In 1674 he returned to Jena as professor of canon law and ordinarius of the judicial college, and in 1680 was appointed president of the regency of Weimar, the duke being a minor. He published 13 elaborate treatises on law, of which the most important are: Syntagma Juris Feu-dalis (Jena, 1653); Syntagmata Jurisprudentiae Civilis (1665); and Jurisprudentia Romano-Germanica Forensis (1670). II Burk-hard Gotthelf, a German jurist, son of the preceding, born in Weimar, May 26, 1671, died in Jena, May 24, 1738. He studied at Jena and various other German and Dutch universities, and in 1692 engaged at Jena with his brother in the pursuit of the philosopher's stone, in which they soon beggared themselves. In 1704 he became professor of history, and in 1712 extraordinary professor of law.
The most important of his numerous works is his Corpus Juris Gentium (Jena, 1743).