8 Lectures — Handbuch. 



In the beginning of this year Haidinger began the 

 series of lectures on mineralogy to the young mining 

 engineers who, from all parts of the empire were ordered 

 to Vienna to perfect their technical education, in order to 

 prove of greater service to the state. Also many other 

 persons not in the service attended these lectures. This 

 course of lectures was repeated every year until 1849, 

 when the institution was enlarged to the Reichsanstalt. 

 In his admirable Handbuch der bestimmenden 

 Mineral ogie (1845) he has given an exposition of the 

 subjects treated of in these lectures. This handbook 

 contains already many of the discoveries of Haidinger ; 

 especially, also, the principal facts of pleochroism, as 

 observed by means of his dichro scope. In the crys- 

 tallographic portion of this work we find numerous ob- 

 servations on form and structure, which at once are 

 simple and highly characteristic ; thus the monoclinic 

 form of barytocalcite is at once related to the rhombohe- 

 dral form of calcite, by the observation of correspondent 

 cleavage faces in the compound crystal represented in 

 Figures 453 and 454, on page 279. In regard to these 

 lectures, von Hauer has remarked that Haidinger con- 

 sidered the lectures themselves of less weight than the 

 work in the actual study of minerals, to which these 

 lectures gave rise. 



The other great publication which marks this period 

 in the labors of Haidinger is the Preliminary Geological 

 Map* of the Austrian Empire. This map, comprising 

 nine large sheets, was finished in March, 1844, printed 

 under date of 1845, from ninety-six stones, in nineteen 

 colors, in 1846. In the actual preparation of this map 

 Haidinger was of course aided by several of his auditors, 

 and especially by F. von Hauer. 



*The more complete and much larger geological map of Austria, resulting from 

 more than twenty years' work of the members of the Geological Institute of Austria, 

 is in the course of publication by F. von Hauer. 



