In the decade between 1860 and 1870 the progress of Darwinism was rapid and continuous. One by one, the few scientific men who still held out were overborne by the weight of evidence. Geology kept supplying fresh instances of transitional forms; the progress of research in unexplored countries kept adding to our knowledge of existing intermediate species and varieties. During those ten years, Herbert Spencer published his 'First Principles,' his 'Biology,' and the remodelled form of his 'Psychology;' Huxley brought out 'Man's Place in Nature,' the 'Lectures on Comparative Anatomy,' and the 'Introduction to the Classification of Animals;' Wallace produced his 'Malay Archipelago' and his 'Contributions to the Theory of Natural Selection;' and Galton wrote his admirable work on 'Hereditary Genius,' of which his own family is so remarkable an instance. Tyndall and Lewes had long since signified their warm adhesion. At Oxford, Rolleston was bringing up a fresh generation of young biologists in the new faith; at Cambridge, Darwin's old university, a whole school of brilliant and accurate physiologists was beginning to make itself both felt and heard in the world of science. In the domain of anthropology, Tylor was welcoming the assistance of the new ideas, while Lubbock was engaged on his kindred investigations into the Origin of Civilisation and the Primitive Condition of Man. All these diverse lines of thought both showed the wide-spread influence of Darwin's first great work, and led up to the preparation of his second, in which he dealt with the history and development of the human race. And what was thus true of England was equally true of the civilised world, regarded as a whole: everywhere the great evolutionary movement was well in progress; everywhere the impulse sent forth from that quiet Kentish home was permeating and quickening the entire pulse of intelligent humanity.