Sir William Ramsay I have quoted on Kelvin's {108} illustration, in the class room, of the term "acceleration." Kelvin maintained speed when he had got it up. Remember that he was lame, and consider his energy. He would dart at an object that stood a few feet from him, on his lecture-bench, use it for whatever demonstration was required, and then dart at another, or at the blackboard, or at the pointer, as if he were a busy bee extracting honey from the flowers. There was certainty about everything he did; no hesitation, no floundering, no hemming and hawing for a word, or the next act. His lameness merely lent emphasis to the fact that he was walking; it did not prevent his swiftness of movement. Across the grounds of the university I toiled after him like "panting time." He gave the impression of readiness for a race, and might challenge you at any minute. His gown was always streaming behind him, his mortar-board cap in imminent danger of blowing off in the breeze stirred by his advance. Well, he had raced the world many years and had always won. Some great men are so impressed by their own greatness that their manner becomes ponderous and vast as if they lived in a belief that they cast shadows on the sun. Not so Lord Kelvin, who never seemed to think that great men thought him a greater than themselves. His manner was simple, gentle, courteous, and direct. He was easy to talk with, and yet he had no small talk. But it was not easy to answer his questions. There was never such a man as he for asking questions unless it were the Chinese Viceroy, Li Hung Chang. Whatever your profession, {109} trade, interests in life, he would put questions that went to the roots of your matter and revealed on his part a greater knowledge of the problems involved than you dreamed existed. By tireless questioning he learned. But where Li Hung Chang turned the results of his questioning to his own benefit, Kelvin applied them to the good of the world. Yet when, in 1896, they celebrated the fiftieth anniversary of his professorship at Glasgow he was, I take it, the most surprised man in all the galaxy of the famous. The dear old gentleman with the domed head, the white hair, and generous white beard seemed to be asking himself, "What next? Why all this fuss and feathers?" But he was apparently genuinely pleased, too, for all the tributes bespoke honest admiration of achievement and character. Fifty-one learned societies, twelve colleges, and twenty-eight universities were represented. They were of all countries. That day the world, and all that was therein, lifted its hat to Lord Kelvin.