to be apprehended from the Romans, with whom Syracuse was allied in the strictest friendship. Hence were seen to arise in an instant, as out of the earth, an incredible number of machines of every kind and size, the very sight of which was sufficient to strike armies with terror and confusion. There are amongst those machines some of which we can scarcely conceive the effects, and the reality of which we might be tempted to call in question, if it were allowable to doubt the evidence of writers, such, for instance, as Polybius, an almost contemporary author, who treated of facts entirely recent, and such as were well known to all the world. But how can we refuse to give credit to the uniform consent of Greek and Roman historians, whether friends or enemies, with regard to circumstances of which whole armies were witnesses and experienced the effects, and which had so great an influence on the events of the war? What passed in this siege of Syracuse shows how far the ancients had carried their genius and art in besieging and in supporting sieges. Our artillery, which so perfectly imitates thunder, has not more effect than the machines of Archimedes had, if indeed it has so much. A burning glass is spoken of, by the means of which Archimedes is said to have burnt part of the Roman fleet. That must have been an extraordinary invention; but, as no ancient author mentions it, it is no doubt a modern tradition without foundation. Burning-glasses were known to antiquity, but not of that kind.[7] After Marcellus had resolved to confine himself to the blockade of Syracuse, he left Appius before the place with two-thirds of his army, advanced with the other into the island, and brought over some cities to the Roman interest. At the same time, Himilco, general of the Carthaginians, arrived in Sicily with a great army, in hopes of reconquering it, and expelling the Romans. Hippocrates left Syracuse with ten thousand foot and five hundred horse to join him, and carry on the war in concert against Marcellus; Epicydes remained in the city, to command there during the blockade. The fleets of the two states appeared at the same time on the coasts of Sicily; but that of the Carthaginians, seeing: itself weaker than the other, was afraid to venture a battle, and soon sailed back to Carthage. Marcellus had continued eight months before Syracuse with Appius, according to Polybius, when the year of his consulship expired. Marcellus employed a part of the second year of the siege in several expeditions in Sicily. On his return from Agrigentum, upon which he had made an ineffectual attempt, he came up with the army of Hippocrates, which he defeated, killing above eight thousand men. This advantage kept those on their duty who had entertained thoughts of going over to the Carthaginians. After this victory, he turned his attention again towards Syracuse; and having sent off Appius to Rome, who went thither to demand the consulship, he put Q. Crispinus in his place.