Charles Darwin autograph letter signed to his financial advisor Thomas Salt. Dated 19 November (1849) from Darwin's home in Down Farnborough, Darwin writes, ''My dear Sir / I am very much obliged for your note of the 13th. & I write now merely, in answer to your query, to say that I will of course leave the month of February to you for looking out for an investment for me, & I much hope that you may succeed. / I remain, dear Sir / yours sincerely / C. Darwin''. Single page on black-bordered bifolium stationery measures 4.5'' x 7'', with docketing on second page by Salt's office. Folds, with small hole at intersecting folds, overall very good condition.