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 innumerable 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 at the Royal Institution his famous address on the Coming of Age of the 'Origin of Species.' The time was a favourable one for reviewing the silent and almost unobserved progress of a great revolution. Twenty-one years had come and gone since the father of modern scientific evolutionism had launched upon the world his tentative work. In those twenty-one years the thought of humanity had been twisted around as upon some invisible pivot, and a new heaven and a new earth had been presented to the eyes of seers and thinkers. One-and-twenty years before, despite the influence of Hutton and of Lyell, the dominant view of the earth's past history revealed but one vast and lawless succession of hideous catastrophes. Wholesale creations and wholesale extinctions, world-wide cataclysms followed by fresh world-wide births of interwoven faunas and floras--these, said Huxley, were the ordinary machinery of the geological epic brought into fashion by the misapplied genius of the mighty Cuvier. One-and-twenty years after, the opponents themselves had given up the game in its fullest form as lost beyond the hope of possible restitution. Some hesitating thinkers, it is true, while accepting the evolutionary doctrine more or less in its earlier form, like Mivart and Meehan, yet refused their assent on one ground or another to the specific Darwinian doctrine of natural selection. Others, like Wallace, made a special exception with regard to the development of the human species, which they supposed to be due to other causes from those implied in the remainder of the organic scale. Yet on the whole, biological science had fairly carried the day in favour of evolution, in one form or another, and not even the cavillers dared now to suggest that whole systems of creation had been swept away _en bloc_, and remade again in different forms for a succeeding epoch, in accordance with the belief which was almost universal among geologists up to the exact moment of the publication of Darwin's masterpiece.