HANSTEEN, Christopher (1784—1873), astronomer and physicist, was born at Christiania, Norway, September 26, 1784. From the cathedral school he went to the uni versity at Copenhagen, where first law and afterwards mathematics formed his main study. In 1806 he taught mathematics in the gymnasium of Frederiksborg, Zeeland, and the following year lie commenced the inquiries in his f ivovtrite branch of science terrestrial magnetism which have made his name famous. He took in 1812 the prize of the Danish Royal Academy of Sciences for his reply to a question on the magnetic axes. Appointed lecturer in 1814, he was in 1816 raised to the chair of astronomy and applied mathematics in the university of Christiania. In 1819 he published his researches on terrestrial magnetism, a work which attracted the notice of the physicists of Europe and particularly of England, where the search for a formula by which the variation of the needle might be found at any given time and place was being actively pursued. The researches were translated into German by P. T. Hanson, under the title Untersuchungen uber den Magnetismus der Erde, with a supplement containing l>eobaclt,tungen der Abweichung und Neigung der Magnet- nadel, and an atlas. The rules there framed for the ob servation of magnetical phenomena have been generally fallowed. Hansteen hoped by them to accumulate analyses for determining the number and position of the magnetic poles of the earth. In prosecution of his researches he visited London, and also Paris and other Continental cities, and travelled over Finland and the greater part of his own country; and in 1828-30 he undertook, in company with Ermann and Due, and with the cooperation of Russia, a Government mission to Western Siberia, the chief aim of which was to find the ideal point of the Asiatic pole of magnetism ten observatories being established in Russia to further the project. The scientific results magnetic, astronomic, and meteorological form the bases of many valuable theories. A narrative of the personal adventures soon appeared (Reise-Erinnerungen a us Sibirioi, 1854 ; Souvenirs d*un voyage en Siberie, 1857); but the chief work was not issued till 1863 (Resultate magnetischer Beobachtungen, &c.). Shortly after the return of the mission, an observatory was erected in the park of Christiania (1833), and Hansteen was appointed director. On his representation a magnetic observatory was added in 1839. In 1835-38 his text-books on geometry and mechanics were published; and in 1842 he wrote his Disquisitiones de mutationibus quas patitur momentum aciis magnetica 1 , &c. He also contributed various papers to different scientific journals, especially the Magazin for Naturvidenskaberne, of which he became joint-editor in 1823. Pie superintended the trigonometrical and topographical survey of Norway, begun in 1837. He was a member of the Royal Society of London, the French Institute, the American Academy of Arts and Sciences, and the Academies of Berlin and St Petersburg. In 1861 he retired from active work, but still pursued his studies, his Observations de V inclination magnetique and Stir les variations seculaires du magnetisme appearing in 1865. Hansteen died at Christiania, April 15, 1873.
HANUSCH, Ignaz Johann (1812–1869), Bohemian savant and philosopher, was born at Prague on the 28th November, 1812. He received his early education in his native city, and taught for a short time in a monastic school there. At the universities of Prague and Vienna, where lie afterwards studied, he directed his attention successively to theology and law, and finally, under the influence of Hegel s writings, to philosophy. After temporarily supply ing in 1835 the place of Lichtenfels, professor of philo sophy at Vienna, he w r as next year appointed ordinary pro fessor of philosophy at Lemberg, whence he passed in the same capacity to Olmiitz in 1847, and two years liter to Prague. There he began a successful course of philosophy in the Czech language, but in 1852 was abruptly suspended from t3aching, owing to his leanings towards Slavism. He still, however, retained his full salary: and in 1860 he was nominated director of the imperial university library at Prague, where he died on the 19th May 1869.
His chief writings, mainly on philosophic and Slavonic subjects, are the following: IVisscnscliaft dcs tilarischcn Mythus (1842) ; text-books in Logic (1843), Ethics (1866), Metaphysics (1846), and Empirical Psychology (1849) ; Gcschichte der Philosophic von ihren Uranfdngen bis zur Schlicssnng der Philofsophcnschulen imtw Justinian (1850); Vorlcsungcn uber die Kullurgcschichte der Menschheit (1849) ; Quellcnkunde und Biblioyrapliie der bohmisch- slowenischcn Litcratur (1868). Besides these and others, Hanuseh wrote some works in Czech, and published the works of the old Slavonic philosopher, Eitter Thomas, in 1852.