hy Alexander von Humboldt. xlvii 



Much of this work might be done on board the Novara. 

 As to Nos. 3 and 4, Kamtschatka, the Kurile and Aleutian 

 Islands, the Red Sea, and the West Indies, it will not be 

 difficult to procure specimens at some future period. 



Our piping times of peace are favourable to the execution 

 of this project, which should be zealously kept in view 

 throughout the Expedition. Travelling as I was, during 

 tlie great wars, I did not dare shrink from the difficulty of 

 having to carry along with me 44 large boxes, as I did on 

 the road through Mexico from Acapulco to Vera Cruz, 

 whence they were sent to Cuba, Philadelphia, and so to 

 Bordeaux. The mechanical labour of having the collections 

 carefully packed, keeping duplicates distinct, and sending 

 away geological, botanical, zoological and ethnographical 

 collections, is itself quite as important as the purely scientific 

 work. 



The exhibition of comprehensive volcanic collections 

 brings to light the strong analogy subsisting between 

 the trachytes belonging to volcanoes, far distant from one 

 another, while it indicates the existence of great differences 

 in the mineralogical composition of volcanoes situated very 

 near each other. My most excellent friend and fellow'- 

 traveller in Siberia, Professor Gustavus Rose, recently sub- 

 jected the trachytes of the Berlin Museum, the greater num- 

 ber of which were collected by myself, to careful crystallo- 

 graphical and chemical investigation. He found oligoclase 

 and pyroxene on the trachytes of Chimborazo, Popocatepetl, 



