Father Zuill levelled his lenses and arranged his glasses in such a way that the bright morning sun, then straight astern, shone lull upon one end, while the other was pointed at the head-most ship, which was now on the lee bow, and beating hard up against a head wind. "Sir Alexander Mathieson will never sail ahead of us in a sunny day, Father Zuill," said Falconer, laughing; "for he fears your operating on his canvas, and burning holes in it;--what he calls your 'damnable hurdy-gurdy.'" "Now, Father Zuill, dost thou really believe in the power of these bits of looking-glass?" asked the admiral; who, with an incredulous smile on his honest face, and his hands thrust into the pockets of his gaberdine, had been watching the futile attempts of the chaplain to ignite the white canvas of the head-most ship. "As truly as I believe that Archimedes burned the Roman fleet with glasses at the siege of Syracuse!" retorted the chaplain. "He used concave mirrors; and if I could only construct a parabolic speculum, the focus of which would reach three bowshots off, and burn there, does it not indubitably follow, that by increasing the scale, I might construct another which would consume a city at three leagues, and scorch to death all who were in it? Hear me, sirs. If _one_ mirror will light a spot one-fourth of its size, at a certain distance, assuredly we may presume that the reflected light of a _hundred_ mirrors, all bearing on the same spot, will render the heat unbearable, and bring the light to that refulgent point at which it engendereth fire. So sayeth Anthemius, who used hexagonal mirrors surrounded by others; and so say Tzetzes, Zonaras, Lucian, and others. We read in ancient history, that the ships of Marcellus were consumed to ashes at the distance of a bowshot, when the sun's rays were at noon. I have heard of as much being done by two concave specula composed of polished brass. A little study, admiral, would make plain to thee (who use the cross-staff for striking the meridian), the geometrical mode of discovering the rectilineal propagation of heat and light, as it was understood by Eustathius and Ptolemy. Thou understandest me?" "May I never more go to sea, if I do," replied the admiral, scratching his beard in sore perplexity. "I think all this sounds as like sorcery as one ropeyarn seems like another. No, no! the gunner to his lintstock, the steersman to his helm, and the cook to the foresheet. Thou to thy book lear, and I to my seamanship. By my father's soul! I would put more reliance in a good cannon-royale with a smooth bore, and a calm sea under the counter, than in all the glass hurdy-gurdies that ever were seen!"