xxvi 



Vienna, known then as the collection of the "k. k. Hofkammer in Miinz 

 und Bergwesen," and later as the " Montanistische Museum." Having 

 completed the arrangement of the collection and published a comprehensive 

 catalogue of it, he began his first course of lectures on the 9th of Feb- 

 ruary, 1843. He gave seven courses, the last being in 1849. During 

 this period he made it one of his chief objects to encourage the members 

 of his class, consisting chiefly of mining students, to undertake original 

 investigations. In the year 1843 he ascertained the existence of trichoism 

 in andalusite from Minas Geraes and in diaspore from Schemnitz, and 

 constructed his " Dichroiscopische Loupe " for exhibiting the contrast of 

 colours between the two fields of oppositely polarized light when certain 

 coloured crystals are viewed through it. On the 1st of April 1844 he 

 discovered the remarkable phenomenon of the " Polarisationsbiischel," or 

 Haidinger's Brushes as it is more commonly named. In 1845 he pub- 

 lished his ' Handbuch der bestimmenden Mineralogie,' and a Report upon 

 the results of mineralogical research during the year 1843. In No- 

 vember 1845 the Society of Freunde der Naturwissenschaften was formed, 

 with Haidinger as its President and editor of their publications, consisting 

 of c Naturwissenschaftliche Abhandlungen,' in four volumes, 4to, and ' Be- 

 richte iiber die Mittheilungen von Freunden der Naturwissenschaften in 

 Wien,' in seven volumes, 8vo. On the 14th of May, 1847, Haidinger was 

 appointed one of the forty Members of the newly founded Imperial Aca- 

 demy of Sciences of Vienna. A Geological Map of the Austrian Empire, 

 prepared, under Haidinger's immediate superintendence, by the most distin- 

 guished Members of the Montanistische Museum, and revised by Franz 

 Bitter v. Hauer, was published in the same year. The Montanistische 

 Museum and its Collections became the nucleus of the " k. k. Geologische 

 Reichsanstalt," an institution founded on the 15th of November, 1849, 

 with Haidinger for its Director, and a staff of local Directors and assistant 

 Geologists. Its province was to collect materials for elucidating the geo- 

 logical knowledge of the whole Austrian Empire. This institution gave a 

 powerful impetus to the culture of the natural sciences throughout the 

 Austrian Empire. During the seventeen years that Haidinger presided 

 over it, he strove with painful accuracy to acknowledge the services of every 

 one of its Members who laboured under his direction. Through Haidin- 

 ger's exertions the Geographical Society of Vienna was established in De- 

 cember 1855, and he became its first President. To his influence also may 

 be traced the origin of the "Werner Verein" for the geological examination 

 of Moravia and Silesia, the " Geologische Verein " for Hungary, and the 

 " Societa Geologica" of Milan, afterwards enlarged into the " Societa 

 Italiana di Scienze Naturali." 



After a long and severe illness he retired on a pension from the 

 office of Director of the Geologische Reichsanstalt on the 7th of Octo- 

 ber, 1866, and was succeeded by his former pupil Franz Ritter v. Hauer. 

 Though enfeebled by illness and frequently unable to quit his room, he 



