It has been said of Erasmus Darwin that no one from his day to ours has ever rivalled him in his achievements in such a wide range of fields. The most striking of Darwin's many talents was his extraordinary scientific insight in physics, chemistry, geology, meteorology, and all aspects of biology—his deepest insight being his evolutionary theory of life. Two of his books, the Zoonomia, which made him famous as the leading medical mind of the 1790s, and The Temple of Nature, show that he believed life developed from microscopic specks in primeval seas through fishes and amphibians to "humankind." But he failed to convince the world about biological evolution—that was left to his grandson Charles. Erasmus was the first person to give a full description of how clouds form and of photosynthesis in plants. He was also an obsessive inventor of mechanical devices, among them a speaking machine, a copying machine, and the steering technique used in modern cars. Substantial donations of Darwin family papers, including over 170 letters written by Erasmus Darwin himself, have made it possible for the author to tell much of the enthralling story of his life in Erasmus' own words.