142 SKETCH OF THE LIFE AND ACHIEVEMENTS 



organic connection of this noted volcano with 

 other phenomena and the condition of the 

 soil, Humboldt published, soon after his return 

 from this expedition, a most interesting account 

 of the geography of this zone, still but im- 

 perfectly known. He next examined the noted 

 salt-mine of Ilezk, the principal place of the 

 Uralian Cossacks ; visited the German colonies 

 on the Volga, in the department of Saratow, 

 the great salt lake Elton, the beautiful settle- 

 ment at Sarepta, and arrived in the middle of 

 October at Astracan on the Caspian Sea. 



The more immediate object of this journey to 

 the Caspian Sea was the minute chemical 

 analysis of its waters being the most important 

 lake known; a task specially undertaken by 

 Gustav Rose. Humboldt instituted likewise 

 barometrical observations, in comparison with 

 his measurements of Orenburg, Sarepta, and 

 Kasan ; and hoped lastly for some zoological 

 acquisitions, intending to collect fishes in the 

 Caspian Sea, in order to complete, by the addi- 

 tion of new specimens, the great work of Cuvier 

 and Valenciennes, on fishes. For this purpose 

 Humboldt and his companions undertook a 

 short fishing voyage on the lake. 



Having accomplished the desired investiga- 

 tions, the travellers returned from Astracan, by 



