hours to noting the results of
experiments, so many to writing and reading, and an hour or two to
exercise in his grounds or a ride, and playing with his children.
Frequently he was stopped for days and even weeks from all intellectual
labor by attacks of vomiting and giddiness. Great, as were his
sufferings on account of ill health, it is not improbable that the
retirement of life which was thus forced on him, to a very large extent
determined his wonderful assiduity in study and led to the production by
him of so many great works.

In later years these attacks were liable to ensue upon prolonged
conversation with visitors, if a subject of scientific interest were
discussed. His wife, who throughout their long and happy union devoted
herself to the care of her husband so as to enable him to do a maximum
amount of work with least suffering in health, would come and fetch him
away after half an hour's talk, that he might lie down alone in a quiet
room. Then after an hour or so he would return with a smile, like a boy
released from punishment, and launch again with a merry laugh into talk.
Never was there an invalid who bore his maladies so cheerfully, or who
made so light of a terrible burden. Although he was frequently seasick
during the voyage of the Beagle, he did not attribute his condition in
later life in any way to that experience, but to inherited weakness.
During the hours passed in his study he found it necessary to rest at
intervals, and adopted regularly the plan of writing for an hour and of
then lying down for half an hour, whilst his wife or daughter read to
him a novel! After half an hour he would again resume his work, and
again after an hour return to the novel. In this way he got through the
greater part of the circulating libraries' contents. He declared that he
had no taste for literature, but liked a story, especially about a
pretty girl; and he would only read those in which all ended well.
Authors of stories ending in death and failure ought, he declared, to be
hung!

He rarely went to London, on account of his health, and consequently
kept up a very large correspondence with scientific friends, especially
with Lyell, Hooker, and Huxley. He made it a rule to preserve every
letter he received, and his friends were careful to preserve his; so
that in the 'Life and Letters' published after his death by his son
Frank--who in later years lived with his father and assisted him in his
work--we have a