To dispose of the accusation of sorcery in respect of Gerbert, supposing that it could be taken seriously, it would be enough to mention that he was the most learned man of his century and having been preceptor of two sovereigns, he owed his election to the gratitude of one of his august pupils. He had extraordinary proficiency in mathematics, and his knowledge of physics may have exceeded that of his epoch; in a word, he was a man of universal erudition and great ability, as the letters which he left bear witness, though he was not a denouncer of kings like the terrible Hildebrand. He chose to instruct princes rather than excommunicate them, and enjoying the favour of two French kings and three emperors, he had no need, as Naudé has judiciously pointed out, to sell himself to the devil for the archbishoprics of Rheims and Ravenna, or for the papacy in succession to these. It is true that he attained the successive positions, to some extent in spite of his merit; it was an age when able politicians were taken for possessed people and those who were learned for enchanters. Gerbert was not only a great mathematician, as we have said, and a distinguished astronomer, but he excelled also in mechanics, and—according to William of Malmesbury—he erected at Rheims such wonderful hydraulic machines that the water itself executed symphonies and played most enchanting airs. Moreover, according to Ditmare, he adorned the town of Magdebourg with a clock which registered all the motions of heaven and the times when the stars rose and set. Finally, by the evidence of Naudé,[219] whom we cite once again with pleasure, he made “that test of brass which was devised so ingeniously that the before-mentioned William of Malmesbury was himself deceived thereby and referred it to Magic. Further, Onuphrius states that he saw in the Farnese library a learned book on geometry composed by this same Gerbert; and for myself I estimate that, without adjudicating on the opinion expressed by Erfordiensis and some others, who regard him as the maker of timepieces and of arithmetic as these exist now among us, all these evidences are sufficiently valid to warrant the conclusion that those who had never heard of cube, parallelogram, dodecahedron, almicantar, valsagora, almagrippa, cathalzem and other names, familiar enough in these days to such as understand mathematics, conceived that they were those of the spirits invoked by Gerbert and that such a multitude of things so rare could not emanate from a single personality in the absence of extraordinary advantages, from the possession of which it followed therefore that he must have been a magician.”