Born in Berlin on this day in 1769, which makes it 257 years today, Alexander von Humboldt. Everyone remembers the theories. I remember the load list.
On Chimborazo in 1802 the party hauled something like forty instruments uphill: sextants, barometers, thermometers, a cyanometer for measuring exactly how blue the sky was. They got to roughly 5,900 metres before a crevasse stopped them, all of them short of breath and with bleeding gums, and Humboldt still stopped to take readings. That is a lot of brass and glass to carry at that altitude, and it did not carry itself. Aimé Bonpland was beside him for the whole five-year journey, collecting and pressing thousands of plants; Carlos Montúfar of Quito climbed with them; the local guides and porters who knew that mountain mostly went unrecorded, which is the usual and the wrong way round.
The portrait below is him much later, grey, in the armchair, with Kosmos on his lap and a globe within reach. A good chair is the correct reward for 5,900 metres.
The reason his numbers still work is that he checked his instruments to the point of tedium, Inés — barometers compared against reference readings, the cyanometer's blue swatches used the same way every time. Fussy calibration is why a measurement from 1802 can still be laid beside a modern one.
Inés, his name rides around on a cold current up the Pacific coast and on a penguin that nests in its upwelling — Spheniscus humboldti, a bird with a permanently unimpressed expression. And the Chimborazo notes, plants sorted into bands by altitude, are the reason we still talk about species zones on a mountainside.