Charles Darwin published The Formation of Vegetable Mould Through the Action of Worms on this date in 1881 (books by this author). It was his last scientific book, and his most successful. In it, he explains that the very ground we walk upon has passed through the bodies of worms and emerged as castings. He also estimated that there are more than 53,000 worms at work in any given acre of land, and reported that they had turned a rocky field behind his uncle’s house into smooth soil over the course of many years. He was fascinated by the work of the earthworm, which he called an “unsung creature which, in its untold millions, transformed the land as the coral polyps did the tropical sea.” On the surface, the study of earthworms seems to have little to do with the work on evolution and natural selection that made him famous. But this book, too, was about the inexorable processes of nature that, over long spans of time, can bring about dramatic changes.
The book started as a paper, which Darwin presented before the Geological Society of London in 1837. In 1842, Darwin spread a layer of chalk fragments over a pasture near his house and observed the worms’ effect on it for almost 30 years. He placed a large, flat stone – which he dubbed the worm stone-in a field and measured the movement of soil as the worms digested the earth beneath the stone. He also kept worms inside the house, examining the effects of bright light and sound. He figured out through trial and error what the worms’ favorite food was: carrots. He was fond of the worms, which were unmoved by art or music – much as Darwin himself remained unmoved by the arts.
By 1881, Darwin’s health was failing, and he remarked to a friend that he wanted to complete his book on worms before he joined them in the local cemetery. He pushed his publisher to bring the book to press as soon as possible. When it was first published, the work of 44 years, Worms was a best-seller, and Darwin received a surprising amount of fan mail. He died six months after the book was published.
Reposted from The Writer’s Almanac