The Invention of Nature

Humboldt also continued to assist young scientists, artists and explorers, often helping them financially despite his own debts. The Swiss geologist and palaeontologist Louis Agassiz, who emigrated to the United States, profited several times from Humboldt’s ‘usual benevolence’, for example. On another occasion Humboldt gave a young mathematician a hundred thalers and also organized free meals at the university for the royal coffee maker’s son. He brought artists to the king’s attention and encouraged the director of the Neues Museum in Berlin to purchase paintings and drawings. Humboldt told a friend that, since he had no family of his own, these young men were like his children.

As the mathematician Friedrich Gauß said, the zeal with which Humboldt helped and encouraged others was ‘one of the most wonderful jewels in Humboldt’s crown’. It also meant that Humboldt ruled over the destinies of scientists across the world. Becoming one of Humboldt’s protégés could make one’s career. It was even rumoured that he now controlled the outcome of elections at the Académie des Sciences in Paris, with candidates first auditioning at Humboldt’s Berlin apartment before they went to the Académie. A letter of recommendation from Humboldt could determine their future, and those who opposed him came to fear his sharp tongue. Humboldt had studied venomous snakes in South America ‘and learned a lot from them’, one young scientist claimed.

Despite the occasional sneer, Humboldt was mostly generous, and explorers, in particular, profited. He encouraged his old acquaintance and Darwin’s friend, the botanist Joseph Dalton Hooker, to travel to the Himalaya, and used his London contacts to convince the British government to finance the expedition – as well as equipping Hooker with copious instructions on what to measure, observe and collect. A few years later, in 1854, Humboldt helped three German brothers, Hermann, Rudolph and Adolf Schlagintweit – the ‘shamrock’, as he nicknamed them – to travel to India and the Himalaya where they were to study the earth’s magnetic fields. These explorers became Humboldt’s small army of researchers, providing the global data he needed to complete Cosmos

. Although he had accepted that he was too old to see the Himalaya himself, his failure to climb those great mountains remained his greatest disappointment – ‘nothing in my life has filled me with a more intense regret.’

He also encouraged artists to travel to the remote corners of the globe, helping them to secure funding, suggesting routes and sometimes complaining when they failed to follow his recommendations. His instructions were exact and detailed. One German artist was equipped with a long list of plants that Humboldt had asked him to paint. He was to depict ‘real landscapes’, Humboldt wrote, rather than idealized scenes as artists had done for the past centuries. He even described where exactly the painter should position himself on a mountain in order to capture the best view.

He wrote hundreds of letters of recommendation. And whenever a letter of support from Humboldt arrived at its destination, the ‘business of deciphering’ began. His handwriting – impossible ‘microscopic-hieroglyphic lines’, as he himself admitted – had always been appalling but with age it deteriorated further. Letters were passed between friends, with each one decrypting another word, phrase or sentence. Even when magnifying glasses were applied to his tiny scrawl, it often took days to work out what Humboldt had written.

In return Humboldt received even more letters. In the mid-1850s, he estimated that 2,500 to 3,000 letters arrived each year. His apartment in Oranienburger Straße, he complained, had become a trading place for addresses. He didn’t mind the scientific letters but he was pestered by what he called his ‘ludicrous correspondence’ – midwives and schoolteachers who hoped for royal medals, for example, or autograph hunters and even a group of women who pursued his ‘conversion’ to their particular religious denomination. He received enquiries about hot-air balloons, requests for help with emigration and ‘offers to nurse me’.

Some letters, though, brought him joy, and in particular those that arrived from his old travelling companion Aimé Bonpland who had never returned to Europe after his departure to South America in 1816. After an almost ten-year imprisonment in Paraguay, Bonpland had suddenly been released in 1831 but had decided to remain in his adopted home. Now in his early eighties, Bonpland farmed some land in Argentina near the border with Paraguay. There he lived in rural simplicity, growing fruit trees and going on occasional plant hunting trips.