8 PKEFACE 



with honest reverence to his great master in Stockholm, 

 while the latter, gradually convinced of the peculiar gifts 

 of his junior, ended by proclaiming with no uncertain 

 voice the importance of his investigations; the one, to 

 use Schonbein's own words, " with his ten talents gaining 

 ten more, while the other none the less strove to put his 

 single talent out at usury." These two men have filled 

 many a page in the history of our science, often with im- 

 perishable writings, and to these their letters serve as a 

 commentary. And I am grateful in no small degree to the 

 Royal Swedish Academy of Sciences at Stockholm, and to 

 their permanent secretary, Prof. G. Lindhagen, for their 

 great kindness and liberality in handing over to me for 

 publication the letters of Schonbein to Berzelius, which 

 are in the possession of the Academy, to which the letters 

 of Berzelius always have immediate reference. I was 

 thus enabled to do what is seldom possible in such a case, 

 namely, to give both sides of the correspondence at 

 once. 



I trust that this little book will be favourably received ; 

 but at all events the two men whose words it contains 

 will secure for it a hearing. 



GEORG W. A. KAHLBAUM. 



STEINABAD, BLACK FOREST, 



1st September 1898. 



