XVII. However, Marcellus escaped unhurt, and sarcastically said to his own engineers: "Are we to give in to this Briareus of a geometrician, who sits at his ease by the seashore and plays at upsetting our ships, to our lasting disgrace, and surpasses the hundred-handed giant of fable by hurling so many weapons at us at once?" For indeed all the other Syracusans were merely the limbs of Archimedes, and his mind alone directed and guided everything. All other arms were laid aside and the city trusted to his weapons solely for defence and safety. At length Marcellus, seeing that the Romans had become so scared that if only a rope or small beam were seen over the wall they would turn and fly, crying out that Archimedes was bringing some engine to bear upon them, ceased assaulting the place, and trusted to time alone to reduce it. Yet Archimedes had so great a mind and such immense philosophic speculations that although by inventing these engines he had acquired the glory of a more than human intellect, he would not condescend to leave behind him any writings upon the subject, regarding the whole business of mechanics and the useful arts as base and vulgar, but placed his whole study and delight in those speculations in which absolute beauty and excellence appear unhampered by the necessities of life, and argument is made to soar above its subject matter, since by the latter only bulk and outward appearance, but by the other accuracy of reasoning and wondrous power, can be attained: for it is impossible in the whole science of geometry to find more difficult hypotheses explained on clearer or more simple principles than in his works. Some attribute this to his natural genius, others say that his indefatigable industry made his work seem as though it had been done without labour, though it cost much. For no man by himself could find out the solution of his problems, but as he reads, he begins to think that he could have discovered it himself, by so smooth and easy a road does he lead one up to the point to be proved. One cannot therefore disbelieve the stories which are told of him: how he seemed ever bewitched by the song of some indwelling syren of his own so as to forget to eat his food, and to neglect his person, and how, when dragged forcibly to the baths and perfumers, he would draw geometrical figures with the ashes on the hearth, and when his body was anointed would trace lines on it with his finger, absolutely possessed and inspired by the joy he felt in his art. He discovered many beautiful problems, and is said to have begged his relatives and friends to place upon his tomb when he died a cylinder enclosing a sphere, and to write on it the proof of the ratio of the containing solid to the contained. XVIII. Such was Archimedes, who at this time rendered himself, and as far as lay in him, the city, invincible.