VICTORY AND REST 165 



experiment that the diversity of form is always due 

 through natural selection to the advantage gained by 

 perfect security of cross-fertilisation, resulting as it 

 invariably does in the production of the finest, strongest, 

 and most successful seedlings. Any variation, however 

 peculiar, which helps to ensure this constant infusion of 

 fresh blood is certain to be favoured in the struggle for 

 life, owing to the superior vitality of the stock it begets. 

 But it is worthy of notice, as showing the extreme 

 minuteness and exhaustiveness of Darwin's method on 

 the small scale, side by side with his extraordinary and 

 unusual power of rising to the very highest and grandest 

 generalisations, that the volume which he devoted to 

 the elucidation of this minor factor in the question of 

 hereditary advantages runs to nearly as many pages as 

 the last edition of the ' Origin of Species ' itself. So 

 great was the wealth of observation and experiment 

 which he could lavish upon the solution of a single, 

 small, incidental problem. 



Even fuller in minute original research was the 

 work which Darwin published in 1880, on 'The Power 

 of Movement in Plants,' detailing the result of innu- 

 merable observations on the seemingly irresponsible yet 

 almost purposive rotations of the growing rootlets and 

 young stems of peas and climbers. Anyone who wishes 

 to see on what a wide foundation of irrefragable fact 

 the great biologist built up the stately fabric of his vast 

 theories cannot do better than turn for instruction to 

 this remarkable volume, which the old naturalist gave to 

 the world some time after passing the allotted span of 

 threescore years and ten. 



It was in the same year (1880) that Huxley delivered 



