IN the first Punic War (264-241 B.C.), Rome improvised a fleet, but her generals were far inferior in naval tactics to the experienced admirals of their opponents. This weakness was overcome by means of the corvus, a drawbridge with a large spike in the middle of the under side. When the ships had drawn up alongside, this was let down upon the enemy's deck, thus making it impossible for him to use the skill of his rowers. It was a crude device, but it turned a sea-battle into a land-battle, and gave victory to the Romans. They exacted a large indemnity and annexed Sicily, their first province. In the following years, Rome seized Sardinia and Corsica, contrary to the terms of the treaty, and also extended her empire over the Po valley. Carthage sought compensation by the conquest of Spain, where she built up a powerful army. The second Punic War (218-202 B.C.) was started by her general, Hannibal, a great strategist, who crossed the Alps and invaded Italy from the North. He had only forty thousand soldiers against the seven hundred thousand of the Roman confederacy, yet, in a series of battles, he nearly overthrew the Republic. Army after army of the Romans was cut to pieces, but even after the fatal day of Cannae (216 B.C.) when seventy thousand soldiers were slaughtered, the Senate refused to despair. The Italian allies stood firm and very few of the Latin cities revolted. Southern Italy went over to Hannibal, but did not give him much real help. The policy of Fabius, nicknamed Cunctator (the Procrasti-nator), that of constantly harassing the enemy but always avoiding pitched battles, was adopted. The revolting cities were won back, and the relieving force, which Hannibal's brother Hasdrubal was bringing from Spain, was annihilated in 207 B.C. Meanwhile, Rome had herself found a general, Scipio, who, after driving the Carthaginians out of Spain, carried the war across into Africa. Hannibal was recalled, but was defeated at the battle of Zama in 202 B.C., and Carthage surrendered. Rome exacted an enormous indemnity and forbade Carthage to build a navy or to make war without the consent of the Romans. Finally, when Carthaginian prosperity began to revive, a pretext for war was found, the people were treacherously deprived of their arms, and their city razed to the ground in 146 B.C. In the next two generations Rome annexed Macedonia and Greece, made Egypt a vassal state, and acquired a large province in Asia Minor (201-133 B.C.).