MUTUAL HELP 491 
It was a unique relationship of minds. Each had had 
the same kind of experience in world-travel, and had observed 
nature, animate and inanimate, with a special interest in the 
same question — namely, how the different forms of life had 
reached their present habitats. In this, indeed, the younger 
man had taken the elder for his model. Before their friend- 
ship and alliance began, Darwin, the born scientific enquii'er 
with philosophic breadth of mind albeit small technical training, 
had advanced far along his memorable line of research. He 
took everything for his province that bore on heredity and 
variation, fertility and decline in living forms, the competition 
they had to meet, their range and movement, the relation 
of them to their fossil predecessors in the same area, the 
geological changes which had determined the ancient courses 
of migration. Hooker, master of a whole branch of science, 
with technical training in it from his childhood up, and equally 
awake to the part played by geologic change in the problems 
of distribution he longed to solve, eagerly placed his vast 
knowledge, his sound criticism, his special observation during 
his later travels, at the disposal of the inspiring friend and 
fellow-worker who had gone so much further on the same 
quest as himself and had pushed it into wider fields than his 
own. 
Each was deeply conscious of his debt to the other. Of 
the discussions they used to have. Hooker records (' Life and 
Letters of Charles Darwin,' ii. 27) : ' I at any rate always left 
with the feeling that I had imparted nothing and carried away 
more than I could stagger under.' Darwin from the earliest 
time feels the immense value of his help, in books lent, 
summaries of results, in published works, letters, conversations. 
* For my own part,' he writes after a visit of Hooker's to Down, 
* I learn more in these discussions than in ten times over 
the number of hours reading.' And again, after reading the 
Antarctic Flora, he speaks of having * extracted more facts 
and views from you than from any other person,' while * my 
pen runs away with me when writing to you ' (March 19, 1845). 
The thanks of a later period are foreshadowed by the 
thanks of the first twelvemonth, as : 
