: x OBITUARY 293 
composed, and that changes in external conditions 
‘favour some and hinder others, 
After a short stay in Cambridge, Darwin resided 
‘in London for the first five years which followed 
his return to England ; and for three years, he held 
the. post of Secretary to the Geological Society, 
though he shared to the full his friend Lyell’s 
objection to entanglement in such engagements. 
Tn fact, he used to say in later life, more than half 
in earnest, that he gave up hoping for work from 
‘men who accepted official duties and, especially, 
Government appointments. Happily for him, he 
was exempted from the necessity of making any 
sacrifice of this kind, but an even heavier burden 
was laid upon him. During the earlier half of his 
‘yoyage Darwin retained the vigorous health of his 
“boyhood, and indeed proved himself to be excep- 
tionally capable of enduring fatigue and privation. 
An anomalous but severe disorder, which laid him 
up for several weeks at Valparaiso in 1834, how- 
ever, seems to have left its mark on his constitution; 
and, in the later years of his London life, attacks 
of illness, usually accompanied by severe vomiting 
and great prostration of strength, became frequent. 
As he grew older, a considerable part of every day, 
even at his best times, was spent in misery ; while, 
not unfrequently, months of suffering rendered work 
of any kind impossible. Even Darwin’s remarkable 
tenacity of purpose and methodical utilisation of 
