On June 7th he attended the Visitation of the Royal Observatory.--From a letter addressed to him by Mr J. Hartnup, of Liverpool Observatory, it appears that there had grown up in the mercantile world an impression that very accurate chronometers were not needed for steam ships, because they were rarely running many days out of sight of land: and Airy's opinion was requested on this matter. He replied as follows on Mar. 3rd: "The question proposed in your letter is purely a practical one. (1) If a ship is _likely_ ever to be two days out of sight of land, I think that she ought to be furnished with two _good_ chronometers, properly tested. (2) For the proper testing of the rates of the chronometers, a rating of the chronometers for three or four days in a meridional observatory is necessary. A longer testing is desirable."--In March he was in correspondence, as one of the Trustees of the Sheepshanks Fund, with the Master of Trinity relative to grants from the Fund for Cambridge Observatory. 1891 From June 16th to July 15th he was at Playford. And again from Oct. 12th to Dec. 2nd (his last visit). Throughout the year his weakness, both of brain power and muscular power, had been gradually increasing, and during this stay at Playford, on Nov. 11th, he fell down in his bed-room (probably from failure of nerve action) and was much prostrated by the shock. For several days he remained in a semi-unconscious condition, and although he rallied, yet he continued very weak, and it was not until Dec. 2nd that he could be removed to the White House. Up to the time of his fall he had been able to take frequent drives and even short walks in the neighbourhood that he was so fond of, but he could take but little exercise afterwards, and on or about Nov. 18th he made the following note: "The saddest expedition that I have ever made. We have not left home for several days."