Both the speculative and the practical sides of his intellect were strongly developed. On the one hand, he had an intense love of knowledge, the desire to attain true knowledge of facts, and to organise them in their true relations. His contributions to pure science never fail to illustrate both these tendencies. His earlier researches brought to light new facts in animal life, and new ideas as to the affinities of the creatures he studied; his later investigations were coloured by Darwin's views, and in return contributed no little direct evidence in favour of evolution. But while the progress of the evolution theory in England owed more to his clear and unwearied exposition than to any other cause, while from the first he had indicated the points, such as the causes of sterility and variation, which must be cleared up by further investigation in order to complete the Darwinian theory, he did not add another to the many speculations since put forward. On the other hand, intense as was his love of pure knowledge, it was balanced by his unceasing desire to apply that knowledge in the guidance of life. Always feeling that science was not solely for the men of science, but for the people, his constant object was to help the struggling world to ideas which should help them to think truly and so to live rightly. It is still true, he declared, that the people perish for want of knowledge. "If I am to be remembered at all," he writes (see volume 2), "I should like to be remembered as one who did his best to help the people." And again, he says in his Autobiographical Sketch, that other marks of success were as nothing if he could hope that he "had somewhat helped that movement of opinion which has been called the New Reformation." This kind of aim in his work, of taking up the most fruitful idea of his time and bringing it home to all, is typified by his remark as he entered New York harbour on his visit to America in 1876, and watched the tugs hard at work as they traversed the bay.] "If I were not a man," [he said], "I think I should like to be a tug." [Two incidents may be cited to show that he did not entirely fail of appreciation among those whom he tried to help. Speaking of the year 1874, Professor Mivart writes ("Reminiscences of T.H. Huxley," "Nineteenth Century", December 1897.) I recollect going with him and Mr. John Westlake, Q.C., to a meeting of artisans in the Blackfriars Road, to whom he gave a friendly address. He felt a strong interest in working-men, and was much beloved by them. On one occasion, having taken a cab home, on his arrival there, when he held out his fare to the cabman, the latter replied, "Oh no, Professor, I have had too much pleasure and profit from hearing you lecture to take any money from your pocket--proud to have driven you, sir!" The other is from a letter to the "Pall Mall Gazette" of September 20, 1892, from Mr. Raymond Blaythwayt, on "The Uses of Sentiment":--