he wrote the first sketch of his theory, and that it was greatly amplified
in 1844. So that, at the date of the first letters of this chapter, we
know that he had a working hypothesis of evolution which did not differ in
essentials from that given in the "Origin of Species."

To realise the amount of work that was in progress during the period
covered by Chapter II., it should be remembered that during part of the
time--namely, from 1846 to 1854--he was largely occupied by his work on the
Cirripedes. (Chapter II./8. "Life and Letters," I. page 346.) This
research would have fully occupied a less methodical workman, and even to
those who saw him at work it seemed his whole occupation. Thus (to quote a
story of Lord Avebury's) one of Mr. Darwin's children is said to have
asked, in regard to a neighbour, "Then where does he do his barnacles?" as
though not merely his father, but all other men, must be occupied on that
group.

Sir Joseph Hooker, to whom the first letter in this chapter is addressed,
was good enough to supply a note on the origin of his intimacy with Mr.
Darwin, and this is published in the "Life and Letters." (Chapter II./9.
Ibid., II., page 19. See also "Nature," 1899, June 22nd, page 187, where
some reminiscences are published, which formed part of Sir Joseph's speech
at the unveiling of Darwin's statue in the Oxford Museum.) The close
intercourse that sprang up between them was largely carried on by
correspondence, and Mr. Darwin's letters to Sir Joseph have supplied most
valuable biographical material. But it should not be forgotten that, quite
apart from this, science owes much to this memorable friendship, since
without Hooker's aid Darwin's great work would hardly have been carried out
on the botanical side. And Sir Joseph did far more than supply knowledge
and guidance in technical matters: Darwin owed to him a sympathetic and
inspiriting comradeship which cheered and refreshed him to the end of his