The article references Andrea Wulf's the Invention of Nature a number of times, which I'd like to give a hearty, emphatic +1 recommendation to. It's a beautifully written biography and the Vintage Books paperback is also a physically beautiful book.
Edit: A documentary[2] based on the book.
[2]https://www.smithsonianchannel.com/details/show/humboldt-epi...
[0] https://www.amazon.com/Adventures-Alexander-Humboldt-Pantheo...