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28 to have undoubtedly had for the King a high personal regard. They were both Hanoverians, and thus there was a sentimental tie between them: and George III., whatever condemnation we may pass on him as a monarch, seems undoubtedly to have taken an intelligent interest in astronomy. In his early days he had made observations at the private observatory at Kew. That he did take an intelligent interest is obvious from a letter which Herschel wrote on 20th May, 1787, to an official at Windsor Castle, in which he requested him to inform the King of the luminosity of a lunar crater, adding that he would himself be at Windsor in the evening to see the King's 10-foot telescope set up for observation.

Despite Herschel's own friendship for the King and his own silence as to the smallness of his salary, there can be no doubt that he was at first sorely handicapped by straitened circumstances. He had made a great financial sacrifice in accepting the post of King's Astronomer. Had he been able to avoid incurring expenses, he could have managed to live on £200 a year; but it was imperative for him to construct larger instruments, and the instruments which he had were in constant need of repair and readjustment. His salary, as has been well said by the late Miss Clerke, "gave him the means of living, but not of observing as he proposed to observe". Accordingly he plunged with enthusiasm into the work of making telescopes for sale. "The goodness of my telescopes," he wrote in his journal, "being already known, I was desired by the King to get some made for those who wished to have them. . . . This business in the end not only proved very lucrative, but also enabled me to make extensive experiments for polishing mirrors by machinery."

Despite the strenuous work of telescope-making, Herschel, while at Datchet, continued his nightly surveys of the sky. His third review of the heavens, which had been commenced at Bath, was completed in January,