151 



82. 

 2of^n §crf(l)cl au gumbolbt. 



Collingwood, 21. Dec. 1843. 

 Hawkhorst. Kent. 



My dear Baron , 



it is now a considerable time since I received 

 your valued and most interesting work on Central 

 Asia, which I should have long ago acknowledged, 

 but that I was unwilling and indeed unable in proper 

 terms to thank you for so flattering and pleasing a 

 mark of your attention, till I had made myself at 

 least in some degree acquainted with the contents. 

 This, however, the continued pression of occupations 

 which leave me little time and liberty for reading has 

 not yet allowed me to do otherwise than partially — 

 and, in fact, it is a work of such close research that 

 I despair of ever being able fully to master all its 

 details. In consequence, I have hitherto limited my- 

 self chiefly to the Climatological researches in the 

 third volume and especially to the memoir on the 

 causes of the flexures of the Isothermal lines which I 

 have read with the greatest interest, and which ap- 

 pears to me to contain by far the most complete and 

 masterly coup-d'oeil ofthat important subject which I 

 have ever met with. In reading this and other parts 

 of your works on this subject and of the „Physique 

 du Globe" in all its departments — that which strikes 



