Hen/danger's Lost Years. 13 



titrations, and for keeping up a correspondence with emi- 

 nent scientists in different quarters of the world. The 

 original investigations of Baidinger during the years 

 from L 840 to 1850 relate mainly to mineralogy, especially 

 in reference to crystal form and optical properties.* In 

 Later years, he made the study o[' cosmical mineralogy a 

 specialty, as is demonstrated by his numerous papers on 

 meteorites in the Sitzungsberichte o( the Academy of 

 Sciences of Vienna. 



The Baidinger-Feier was the culminating point oi' Ilai- 

 dinger's official life. Near the close iA' the same year 

 bis exceeding and protracted labors laid him low by a 

 cerebral form <>f typhus: although he recovered from it, 

 be was unable to continue in liis position. The govern- 

 ment rewarded it- faithful servant by relieving him from 

 all his duties, without diminishing his salary. Franz 

 von Bauer, who. from the organisation of tin- Reichsan- 

 stalt. was tin- first geologist of the institution, was ap- 

 pointed Baidinger's successor. October, 1866. 



Although his physical strength was shaken, Baidinger 

 retained, according to the testimony of Von Bauer, a 

 wonderful freshness of mind, which not only manifested 



Lt8elf by the vivid interest wherewith he followed the 

 progress of science, hut also in the continuation of his 

 own individual researches, especially into the nature of 

 meteoril 



Numerous letters received from Baidinger enable me 



to corroborate the above expressions. Judging from the 



>>f these letters, one might think they hud been 



written by a man in the prime of life, except for the 



illy expressed regret of the failing of physical 



. expert ;.•■ '.\ ae in this branch became apparent, even to the general public, 



- whon he. by merely looking tit the great <liani<.n<i <»f Dupolsal through his 



diehroscope, proved the Bo-called diamond to be simply a topaz. Dupolsal hud 



value-! florins. Haidlnger's observation through "the dlchro- 



scope proved the -tone to be worth, at most, the millionth part of that sum. 



