The Formation of Vegetable Mould
Through the Action of Worms with Observations on Their Habits
The last book of Darwin which perfectly shows how rigorous he was and that he was such a talent for discovering of long-term phenomena.
I learnt about this work from R. Dawkins and was quite courious what Darwin had to tell us about those ubiquitous creatures – earth-worms.
Darwin was an expert on long-term phenomena – he discovered evolution and was fascinated by tectonics. This is another phenomenon – worms forming mould, changing rocks into a fertile fields… in span of many years and centuries.
This work is not an easy reading as it includes a lots of (sometimes boring) facts about worms, their habits, their influence on shaping grounds all over the world, but it nicely shows his chiefly scientific approach to the problem. He wants to convince readers that worms play crucial role in formation of mould which is in turn crucial for our crops and for many animals and plants and (for me at least) he succeeds as he provides a plenty of observations, statistics and arguments in favour of his hypotheses (later theories and then broadly accepted facts).
I see the book as a window to his (and in general, a scientific) approach to observe, describe and explain natural phenomena around us. In this it is very similar to On the origin of species.