I am, from what I have seen of scientific men, that there is an intimate connection between the health of the moral faculties and the health of the inductive ones; and that the proud, self-conceited, and passionate man will see nothing: perhaps because nothing will be shown him. But we must leave Archimedes for a man not perhaps so well known, but to whom we owe as much as to the great Syracusan—Hipparchus the astronomer. To his case much which I have just said applies. In him astronomic science seemed to awaken suddenly to a true inductive method, and after him to fall into its old slumber for 300 years. In the meantime Timocharis, Aristyllus, and Conon had each added their mites to the discoveries of Eratosthenes: but to Hipparchus we owe that theory of the heavens, commonly called the Ptolemaic system, which, starting from the assumption that the earth was the centre of the universe, attempted to explain the motions of the heavenly bodies by a complex system of supposed eccentrics and epicycles. This has of course now vanished before modern discoveries. But its value as a scientific attempt lies in this: that the method being a correct one, correct results were obtained, though starting from a false assumption; and Hipparchus and his successors were enabled by it to calculate and predict the changes of the heavens, in spite of their clumsy instruments, with almost as much accuracy as we do now. For the purpose of working out this theory he required a science of trigonometry, plane and spherical: and this he accordingly seems to have invented. To him also we owe the discovery of that vast gradual change in the position of the fixed stars, in fact, of the whole celestial system, now known by the name of the precession of the equinoxes; the first great catalogue of fixed stars, to the number of 1080; attempts to ascertain whether the length of years and days were constant; with which, with his characteristic love of truth, he seems to have been hardly satisfied. He too invented the planisphere, or mode of representing the starry heavens upon a plane, and is the father of true geography, having formed the happy notion of mapping out the earth, as well as the heavens, by degrees of latitude and longitude. Strange it is, and somewhat sad, that we should know nothing of this great man, should be hardly able to distinguish him from others of the same name, but through the works of a commentator, who wrote and observed in Alexandria 300 years after, during the age of the Antonines. I mean, of course, the famous Ptolemy, whose name so long bore the honour of that system which really belonged to Hipparchus.