The Expression of the Emotions in Man and Animals in the laying out of the sandwalk, his "thinking path", at Down House in Kent in 1846. These aspects of Darwin's personal life are discussed in John Bowlby's (1990) psychoanalytic biography of Darwin. Darwin emphasises a shared human and animal ancestry in sharp contrast to the arguments deployed in Charles Bell's "Anatomy and Philosophy of Expression" (1824). Bell claimed that the facial muscles were divinely designed in order to express uniquely human feelings. Eager to stress the differences between human and animal communication, Bell wrote: "Expression is to the passions as language is to thought." In "The Expression", Darwin reformulates
The Formation of Vegetable Mould through the Action of Worms went the less controversial direction of the lowly worm. His network of correspondents and fans responded to his interest and "earthworm anecdotes began surfacing in his mountain of mail". He had been interested in earthworms "since his first fishing days at The Mount and flirting days at Maer". Still, other work constrained him. Broken off from "Descent", he had to finish his next work "The Expression of the Emotions in Man and Animals". By 1876, with his first grandson on the way, he felt his writing life was nearly over, with so much unfinished. He wanted to write on earthworms