"1847, October 7th.--Dined at Carclew, and spent a very interesting evening. We met Professor Adams, the Bullers, the Lord of the Isles, and others. Adams is a quiet-looking man, with a broad forehead, a mild face, and an amiable and expressive mouth. I sat by him at dinner, and by general and dainty approaches got at the subject on which one most wished to hear him speak. He began very blushingly, but went on to talk in most delightful fashion, with large and luminous simplicity, of some of the vast mathematical facts with which he is so conversant. The idea of the reversed method of reasoning, from an unknown to a known, with reference to astronomical problems dawned on him when an undergraduate, with neither time nor mathematics to work it out. The opposite system had always before been adopted. He, in common with many others, conceived that there must be a planet to account for the disturbances of Uranus; and when he had time he set to work at the process, in deep, quiet faith that the fact was there, and that his hitherto untried mathematical path was the one which must reach it; that there were no anomalies in the universe, but that, even here, and now, they could be explained and included in a higher law. The delight of working it out was far more than any notoriety could give, for his love of pure truth is evidently intense, an inward necessity, unaffected by all the penny trumpets of the world. Well, at length he fixed his point in space, and sent his mathematical evidence to Airy, the Astronomer Royal, who locked the papers up in his desk, partly from carelessness, partly from incredulity, for it seemed to him impossible that a man whose name was unknown to him should strike out a new path in mathematical science with any success. Moreover, his theory was, that if there were a planet, it would not be discovered for one hundred and sixty years; that is, until two revolutions of Uranus had been accomplished. Then came Leverrier's equally original, though many months younger, demonstration; Gull's immediate verification of it by observation; and then the other astronomers were all astir. Professor Adams speaks of those about whom the English scientific world is so indignant in a spirit of Christian philosophy, exactly in keeping with the mind of a man who has discovered a planet. He speaks with warmest admiration of Leverrier, specially of his exhaustive method of making out the orbits of the comets, imagining and disproving all tracks but the right one--a work of infinite labour. If the observer could make out distinctly but a very small part of a comet's orbit, the mathematician would be able to prove what its course had been through all time. They enjoyed being a good deal together at the British Association Meeting at Oxford, though it was unfortunate for the intercourse of the fellow-workers that one could not speak French nor the other English. He had met with very little mathematical sympathy, except from Challis, of the