In order to make up for this hard necessity, they resolved to land in Sicily on their return, and, if possible, reduce some cities which the Carthaginians still retained in that island. Such was the plan of the consuls, but it was vehemently opposed by the pilots of the fleet, who represented to them, that as the season was far advanced, the most prudent measure would be to sail directly for Italy, and not go round the northern coast of Sicily, as the consuls wished. The latter, however, persisted in their resolution; the consequences were extremely fatal; a most violent storm arose, during which the greater part of the fleet was destroyed or rendered completely useless, either foundering, or being driven on shore. All the sea coast from Camarina to Pachynum, was covered with dead bodies of men and horses, as well as with the wrecks of the ships. The exact number of ships that were lost is differently represented by different authors, but according to the most accurate account, out of 370 which composed the fleet, only eighty escaped. Besides the destruction of these vessels, a numerous army was lost, with all the riches of Africa, which had been amassed and deposited in Clupea, by Regulus, and which was in the act of being conveyed to Rome.

The Carthaginians, animated by the news of this event, resolved to attempt the subjugation of Sicily, Africa being now liberated from the enemy. But the Romans, by incredible efforts, fitted out a new fleet in the short space of three months, consisting of 120 ships; which, with the old vessels which had escaped, made up a fleet of 250 sail. With these, they passed over to Sicily, where they were successful in reducing the Carthaginian capital in that island.

The next year they sent to sea a fleet of 260 ships to attempt the reduction of Lilibæum, but this place being found too strong, the consuls directed their course to the eastern coast of Africa, on which they carried on a predatory warfare. Having filled their ships with the spoils, they were returning to Italy, when they narrowly escaped shipwreck. On the coast of Africa, there were two sand-banks, called the Greater and Lesser Syrtes, which were very much dreaded by the ancients, on account of their frequently changing places; sometimes being easily visible, and at other times considerably below the water. On the Lesser Syrtes the Roman fleet grounded; fortunately it was low water, and moderate weather at the time, so that on the return of flood tide, the vessels floated off, with little or no damage, but the consuls were dreadfully alarmed.

This, however, was only a prelude to real disaster: the fleet arrived safe at Panormus, where they remained a short time. On their departure for Italy, the wind and weather were favourable till they reached Cape Palinurus; here a dreadful storm arose, in which 160 galleys, and a considerable number of transports, were lost. This second storm seems to have so dispirited the Roman senate, that they resolved to confine their efforts to land, and accordingly a decree was issued, that, as it seemed the will of the gods that the Romans should not succeed against their enemy by sea, no more than fifty vessels should in future be equipped; and that these should be employed exclusively in protecting the coasts of Italy, and in transporting troops to Sicily.

This decree, however, was not long acted upon; for the Carthaginians, perceiving that the Romans no longer dared to meet them at sea, made such formidable preparations for invading Sicily, by equipping a fleet of 200 sail, and raising an army of 30,000 men, besides 140 elephants, that the Romans, being reduced to the alternative of either losing that valuable island, or of again encountering their enemy at sea, resolved on the latter measure. Accordingly a new fleet was built, consisting of 240 galleys, and sixty smaller vessels, and Lilibæum was besieged by sea and land. This city was deemed impregnable, and as it was the only place of retreat for the Carthaginian armies in Sicily, it was defended with the utmost obstinacy.

During this siege, two bold and successful enterprises were undertaken for the purpose of supplying the garrison with provisions. The Romans had shut up the port so closely, that the governor could have no communication with Carthage: nevertheless, Hannibal, the son of Hamilcar, resolved to enter it with a supply of provisions. With this intention, he anchored with a few vessels under an island near the coast, and as soon as a strong south wind arose, he set all sail, and plied his oars with so much vigour and alacrity, that he passed safely through the midst of the Roman fleet, and landed 10,000 men and a considerable quantity of provisions. Having succeeded thus far, and being convinced that the Romans would be on the alert to prevent his sudden escape, he resolved to intimidate them, if possible, by the open boldness of the attempt; and in this also he succeeded.

Shortly afterwards the harbour was again so closely blockaded, that the senate of Carthage were quite uninformed of the state and resources of the garrison. In this emergency, a Rhodian, of the name of Hannibal, undertook to enter the harbour, and to come back to Carthage with the requisite and desired intelligence. The Roman fleet lay at anchor, stretched across the mouth of the harbour. Hannibal, following the example of his namesake, with a very light galley of his own, concealed himself near one of the islands which lie opposite to Lilibæum. Very early in the morning, before it was light, with a favourable wind blowing rather strong, he succeeded in getting through the Roman fleet, and entered the port. The consul, mortified at this second enterprise, ordered ten of his lightest vessels to lie as close as possible to each other, across the mouth of the harbour; and that they might not be taken by surprise and unprepared, he further directed that the men should constantly have their oars in their hands, stretched out, so as to be ready to plunge them into the water at a moment's warning. The skill and experience of the Rhodian, however, and the extreme lightness and celerity of his vessel, rendered all these precautions unavailing; for, not content with securing his escape, he mocked the Romans, by often lying to till they came near him, and then rowing round them. The Carthaginian senate were now able to have frequent communication with the garrison by means of this Rhodian: his success, and the recompence which rewarded it, induced several Carthaginians to make the same attempt. They were all successful except one, who, not knowing the force and direction of the currents, was carried by them ashore, and fell into the power of the Romans. The Rhodian still continued to pass between the besieged and Carthage; but his good fortune was near an end. The Romans had fitted out the Carthaginian galley which they had captured, and "waited with impatience for a fresh insult from the Rhodian: it was not long before he entered the port in the night time, according to custom, and was preparing to sail out in broad day, not knowing that the Romans were now masters of a galley which was as good a sailer as his own. He weighed anchor with great confidence, and sailed out of the port in sight of the enemy's fleet, but was greatly surprized to see the Romans pursue him close, and at length come up with him, notwithstanding the lightness of his vessel. He had now no way left but to engage them, which he did with an undaunted bravery; but the Romans, who were all chosen men, soon put an end to the dispute. The Rhodian vessel was boarded and taken with all her crew. The Romans being now in possession of two light galleys, shut up the port so effectually, that no Carthaginian ever after attempted to enter it."

The following year the Romans were obliged to convert the siege into a blockade, in consequence of the Carthaginians having succeeded in destroying all their works. One of the consuls was P. Claudius Pulcher, an obstinate and ambitious man, who, contrary to the advice of those who were better skilled in maritime affairs, and better acquainted with the Carthaginians than he was, determined to surprize Drepanon, where the Carthaginian admiral was posted. Claudius had under his command a fine and formidable fleet of 120 galleys; with these he sailed from before Lilibæum in the night time, having taken on board a great number of the best troops employed in the blockade of that place. At break of day, Asdrubal, the Carthaginian admiral, was surprized to perceive the hostile fleet approaching Drepanon: he formed his plan immediately, preferring an immediate engagement to the certainty of being shut up in the harbour. Accordingly, with ninety ships, he sailed out, and drew them up behind some rocks which lay near the harbour. As the Romans had not perceived him come out, they continued to sail on without forming themselves into line of battle, when as they were about to enter the harbour, the Carthaginians attacked them, with such celerity and vigour, that, being taken quite unprepared, they were thrown into confusion. Claudius might still have saved his fleet by immediate flight, but this he absolutely refused to do, notwithstanding the strong and urgent remonstrances of his officers. By great exertions the Roman fleet was formed into line of battle, on a lee shore, and close to rocks and shoals. It was on this occasion, that the Romans' veneration for auguries was so dreadfully shocked, by Claudius exclaiming, when the sacred chickens refused to feed, "If they will not feed, let them drink," at the same time ordering them to be thrown into the sea. The bad omen, and the sacrilegious insult, added to the situation in which they were placed, and their want of confidence in Claudius, seemed to have paralysed the efforts of the Romans: they fought feebly: the enemy boarded their ships without difficulty or resistance; so that ninety vessels were either taken or driven ashore, 8,000 of their seamen and soldiers were killed, and 20,000 taken prisoners. As soon as Claudius perceived the probable result of the battle, he fled precipitately with thirty vessels. The Carthaginians did not lose a single ship or man on this occasion. This was the most signal and disastrous defeat which the Romans had suffered at sea since the commencement of the war. According to Polybius, Claudius was tried, condemned, and very severely punished.

The other consul, Lucius Pullus, was not more successful, though his want of success did not, as in the case of Claudius, arise from ignorance and obstinacy. He was ordered to sail from Syracuse with a fleet of 120 galleys, and 800 transports, the latter laden with provisions and stores for the army before Lilibaeum. As the army was much pressed for necessaries, and the consul himself was not ready to put to sea directly, he sent the quaestors before him with a small squadron. The Carthaginians, who were very watchful, and had the best intelligence of all the Romans were doing, having learnt that the consul was at sea with a large fleet, sent 100 galleys to cruize off Heraclea. As soon as the squadron under the quaestors came in sight, the Carthaginian admiral, though he mistook it for the consular fleet, yet resolved to engage it: but the quaestors, having received orders not to hazard a battle if they could possibly avoid, took refuge behind some rocks, where they were attacked by the enemy. The Romans defended themselves so well with balistae and other engines, which they had erected on the rocks, that the Carthaginian admiral, after having captured a few transports, was obliged to draw off his fleet.

In the mean time, the light vessels, employed on the lookout, informed him that the whole consular fleet were directing their course for Lilibaeum: his obvious plan was to engage this fleet before it could join that of the quæstors; he therefore steered his course to meet them. But the consul was equally averse with the quaestors to hazard the supply of the army by a battle, and he, therefore, also took shelter near some rocks. The Carthaginian admiral was afraid to attack him in this position, but resolved to watch him: while thus employed his pilots observed certain indications of an approaching storm, which induced him to take shelter on the other side of Cape Pachynum. He had scarcely doubled the cape, when the storm arose with such violence that the whole Roman fleet was destroyed. According to Polybius, not one vessel, not even a plank, was saved out of a fleet which consisted of 120 galleys and 800 transports.