1Thomas Jefferson to Alexander von Humboldt, 6 March 1809 (Jefferson Papers)
I recieved safely your letter of May 30. & with it your astronomical work & Political essay on...
2From Thomas Jefferson to Alexander von Humboldt, 9 June 1804 (Jefferson Papers)
Thos: Jefferson asks leave to observe to Baron de Humboldt that the question of limits of...
3Thomas Jefferson to Alexander von Humboldt, 6 December 1813 (Jefferson Papers)
I have to acknolege your two letters of Dec. 20. & 26. 1811. by mr Correa , and am first to thank...
4Thomas Jefferson to Alexander von Humboldt, 13 June 1817 (Jefferson Papers)
The reciept of your Distributio geographica plantarum, with the duty of thanking you for a work...
5From Thomas Jefferson to Alexander von Humboldt, 28 May 1804 (Jefferson Papers)
I recieved last night your favor of the 24th. and offer you my congratulations on your arrival...
6Thomas Jefferson to Alexander von Humboldt, 14 April 1811 (Jefferson Papers)
The interruption of our intercourse with France , for some time past, has prevented my writing to...