At the time when he took his degree (1823) and for many years afterwards there was very great activity of scientific investigation and astronomical enterprise in England. And, as in the times of Flamsteed and Halley, the earnest zeal of men of science occasionally led to much controversy and bitterness amongst them. Airy was by no means exempt from such controversies. He was a man of keen sensitiveness, though it was combined with great steadiness of temper, and he never hesitated to attack theories and methods that he considered to be scientifically wrong. This led to differences with Ivory, Challis, South, Cayley, Archibald Smith, and others; but however much he might differ from them he was always personally courteous, and the disputes generally went no farther than as regarded the special matter in question. Almost all these controversial discussions were carried on openly, and were published in the Athenaeum, the Philosophical Magazine, or elsewhere; for he printed nearly everything that he wrote, and was very careful in the selection of the most suitable channels for publication. He regarded it as a duty to popularize as much as possible the work done at the Observatory, and to take the public into his confidence. And this he effected by articles communicated to newspapers, lectures, numerous Papers written for scientific societies, reports, debates, and critiques. His strong constitution and his regular habits, both of work and exercise, are sufficient explanation of the good health which in general he enjoyed. Not but what he had sharp touches of illness from time to time. At one period he suffered a good deal from an attack of eczema, and at another from a varicose vein in his leg, and he was occasionally troubled with severe colds. But he bore these ailments with great patience and threw them off in course of time. He was happy in his marriage and in his family, and such troubles and distresses as were inevitable he accepted calmly and quietly. In his death, as in his life, he was fortunate: he had no long or painful illness, and he was spared the calamity of aberration of intellect, the saddest of all visitations. CHAPTER II. FROM HIS BIRTH TO HIS TAKING HIS B.A. DEGREE AT CAMBRIDGE. FROM JULY 27TH 1801 TO JANUARY 18TH 1823.