Miss Nightingale's interest in details of sanitary reform was gradually merged into larger questions. Recurrent Indian famines gave a new turn to her thoughts. "I have been doing sanitary work for India for 18 years," she explained in a letter to Lord Houghton (Nov. 27, 1877); "but for the last four have been continually struck by this dreadful fact: What is the good of trying to keep people in health if you can't keep them in life? These ryots are being done to death by floods, by drought, by Zemindars, and usurers. You must live in order to be well." This indisputable proposition appealed strongly to her emotions. "My mind," she wrote to Mr. Chadwick (Sept. 14, 1877), "is full of the dying Indian children, starved by hundreds of thousands from conditions which have been made for them, in this hideous Indian famine.... How I wish that some one would now get up an agitation in the country--as Mr. Gladstone did as regards Bulgaria--which should say to the country, _You shall_, as regards Indian famines and the means of preventing them, among which Irrigation and Water Transit must rank foremost; if we had given them water, we should not now have to be giving them bread." Miss Nightingale had reached this conclusion by herself in 1873, and it was strongly confirmed in the following year. In February 1874 she was moved to write to Sir Arthur Cotton, "the greatest living master," as she truly called him, "of the Water Question." Her letter--the letter of one enthusiast to another--greatly delighted the old Anglo-Indian. "If," he wrote (Feb. 4), "fifty years of hard work and contempt had produced no other return but a letter from you, it would be an honour beyond what I deserve. The plot is now rapidly thickening, and I have not the smallest doubt that your having taken up this great subject will turn the scale. It is impossible for any person not resident in India to conceive the strength of the prejudice in the minds, not only of the civil officials, but of multitudes out of office on both the points of irrigation and navigation in India. I am assured that there is not a single person in high office now in India who is not in his heart opposed to them both. But we have arrived at a most remarkable crisis now, first in the occurrence of this most terrible famine, and, second, in the revolution in the India Office. Lord Salisbury will think for himself in spite of an Indian Council composed--with only the exception of Sir B. Frere--of men of incurable old Indian bias." Sir Arthur Cotton's inventive genius has left a permanent impress upon India; but he was now _en disponibilité_, and he was one of those enthusiasts who, when out of office and unable to carry on their plans, conceive the world to be in wilful conspiracy against them. Moreover, in urging the case for canals, he overstated it by too uncompromising a criticism of railways. During ensuing years Sir Arthur Cotton was one of the most voluminous of Miss Nightingale's correspondents.