RESIDENCE AT BERLIN TO THE REVOLUTION OF JULY. 149 



years in honour of its organisation, but from his intimacy with 

 Bitter, Dove, Ehrenberg, and other succeeding presidents, he was 

 naturally induced to take a lively interest in the proceedings. 

 While the last volume of the ' Relation historique ' was in course 

 of publication at Paris in 1826, Humboldt brought out a new 

 edition of the ' Aspects of Nature,' into which he introduced the 

 c Grenius of Ehodes,' while the various notes and illustrations 

 were added in a new form. 1 Even during his summer visits to 

 Teplitz, whither he annually accompanied the king in almost 

 unbroken regularity between the years 1828 and 1839, and 

 which, though enjoyed at first, were afterwards heavily com- 

 plained of as the journeys to the ' eternal springs,' he availed 

 himself of this period of recreation for carrying out magnetic 

 observations, not only at Teplitz but at the great Milischauer 

 and at Prague. He also made several geological excursions, and 

 in returning to Berlin on one occasion paid a visit to Freiberg, 

 to compare with Reich and Freiesleben the variation in the 

 inclination of the needle as observed in the mine or above 

 ground, though the injury to his arm prevented him making 

 the descent of an upright shaft. It was ,a pleasure to greet 

 once more the friend of his youth, to whom he sent on April 

 4, 1829, a bust that had been recently taken, with the affec- 

 tionate message that he should carry with him as far as the 

 shores of the Irtysch and the Kirghissian steppes of Ischim the 

 thought of all for which he was indebted to Freiesleben. 



The Asiatic expedition, during which Humboldt was absent 

 from Berlin from April 12 to December 28, 1829, has already 

 been described. It is scarcely necessary to remark that this im- 

 portant undertaking engaged the attention of his active mind 

 for a considerable number of years, not merely in the prepara- 

 tion for its successful accomplishment, but in the arrangement 

 and publication of the results obtained. In the autumn of 1827, 

 while engaged in a correspondence with Count Cancrin, the 

 benevolent minister of an enlightened despotism, and with 

 Bolivar, the revolutionary hero of South America, in reference 

 to the subject of platinum, ' the cherished visions ' of Siberia 

 and of Tobolsk, 'the dream of his early youth,' were ever 





Briefwechsel mit Yarnhagen/ p. 2. 



