He wore a white necktie, a black dress-coat, buttoned up, but not so much so that it hid a figured dark-blue and white waistcoat.

He was a little deaf.

He told me that he was eighty-nine years old, and that he and Bonpland, alone, were living of those who in early life were on expeditions together; that Bonpland was eighty-five, and much the more vigorous of the two.
"He said that we had gone backwards, morally, in America since he was there,--that then there were strong men there: Jefferson, and Hamilton, and Madison; that the three months he spent in America were spent almost wholly with Jefferson.
"In the course of conversation he told me that the fifth volume of 'Cosmos' was in preparation.

He urged me to go to see Argelander on my way to London; he followed me out, still urging me to do this, and at the same time assured me that Kansas would go all right.
"It was singular that Humboldt should advise me to use the sextant; it was the first instrument that I ever used, and it is a very difficult one.

No young aspirant in science ever left Humboldt's presence uncheered, and no petty animosities come out in his record.