PEEFACE. xi 



boldt to Christian Carl Josias Baron von Bunsen.' Various 

 eloges and speeches commemorative of the centenary of 

 Humboldt's birth were published by different academies, geo- 

 graphical societies, and other associations, not only in Europe, 

 but also in America, among which we can refer only by name 

 to those of Agassiz, Bastian, Dove, and Ehrenberg ; nor did 

 there fail to appear on the occasion of the celebration many 

 other smaller essays and popular biographies. 



During the previous year I had already received a communi- 

 cation from the firm of F. A. Brockhaus of Leipzig, offering to 

 undertake the publication of the work in the event of my 

 preparing a life of Humboldt. This intelligence helped to 

 mature my scheme, and I resolved to attempt to enlist the 

 co-operation of a number of scientific men in the work of 

 composing a comprehensive biography of Humboldt, in which 

 justice should be done to his labours in the various branches of 

 science. The centenary of his birth appeared to me to offer a 

 most appropriate opportunity for the commencement of such a 

 literary memorial the more so, as at that time there had been 

 no proposition to erect in his native city a monument in 

 bronze. 



My scheme met with ready sympathy from my friends in 

 Berlin. Professor W. Forster placed in my hands the manu- 

 scripts deposited at HumbcSlt's death in the Berlin Observa- 

 tory, and promised to afford me all the assistance in his power ; 

 Frau von Biilow, a niece of Humboldt, granted me the use of 

 the Journals kept by him during his travels in America and 

 Asia, and allowed me to have access to all the letters in her 

 possession ; while Professors Dove and Du Bois-Reymond ex- 

 pressed their willingness to join in the undertaking. 



The work is divided into two Parts. The first consists of the 

 story of his life, the second, of a discussion in detail of his 

 labours in the various departments of science. The first part 

 is subdivided into three sections, treating of his Youth, his 

 Manhood, and his Old Age ; while the second part, consisting 



