The boys were highly edified by this statement of the difficulty which Archimedes's friends found in making him take a bath, and chaffed Jack, who had asked if he were not the inventor of bath-tubs. When the reading from Plutarch was over, Fergus asked if that were all, and was disappointed that there was nothing about the setting of ships on fire by mirrors. It is one of the old stories of the siege of Syracuse, that he set fire to the Roman ships by concentrating on them the heat of the sun from a number of mirrors. But this story is not in Livy, nor is it in Plutarch, though, as has been seen, they were well disposed to tell what they knew which was marvellous in his achievements. It is told at length and in detail by Zonaras and Tzetzes, two Greek writers of the twelfth century, who must have found it in some ancient writers whose works we do not now have. "Archimedes," says Zonaras,[3] "having received the rays of the sun on a mirror, by the thickness and polish of which they were reflected and united, kindled a flame in the air, and darted it with full violence upon the ships, which were anchored within a certain distance, in such a manner that they were burned to ashes." The same writer says that Proclus, a celebrated "mathematician" of Constantinople, in the sixth century, at the siege of Constantinople set fire to the Thracian fleet by means of brass mirrors. Tzetzes is yet more particular. He says that when the Roman galleys were within a bow-shot of the city walls, Archimedes brought together hexagonal specula (mirrors) with other smaller ones of twenty-four facets, and caused them to be placed each at a proper distance; that he moved these by means of hinges and plates of metal; that the hexagon was bisected by the meridian of summer and winter; that it was placed opposite the sun; and that a great fire was thus kindled, which consumed the ships. Now, it is to be remembered that these are the accounts of writers who were not so good mechanics as Archimedes. It should be remembered, also, that in the conditions of war then, the distance at which ships would be anchored in a little harbor like that of Syracuse was not great. By "bow-shot" would be meant the distance at which a bow would do serious damage. Doubtful as the story of Zonaras and Tzetzes seems, it received unexpected confirmation in the year 1747 from a celebrated experiment tried by the naturalist Buffon.