After two years were expired, he prepared to cross the sea again, and revenge himself on Cassibellaun, who having intelligence of his design, everywhere fortified his cities, repaired the ruined walls, and placed armed men at all the ports. In the river Thames, on which Cæsar intended to sail up to Trinovantum, he caused iron and leaden stakes, each as thick as a man's thigh, to be fixed under the surface of the water, that Cæsar's ships might founder. He then assembled all the forces of the island, and took up his quarters with them near the sea-coasts, in expectation of the enemy's coming. CHAP. VII.--_Cæsar a second time vanquished by the Britons._ After he had furnished himself with all necessaries, the Roman general embarked with a vast army, eager to revenge himself on a people that had defeated him; in which he undoubtedly would have succeeded, if he could but have brought his fleet safe to land; but this he was not able to do. For in sailing up the Thames to Trinovantum, the ships struck against the stakes, which so endangered them all on a sudden, that many thousands of the men were drowned, while the ships being pierced sank into the river. Cæsar, upon this, employed all his force to shift his sails, and hastened to get back again to land. And so those that remained, after a narrow escape, went on shore with him. Cassibellaun, who was present upon the bank, with joy observed the disaster of the drowned, but grieved at the escape of the rest; and upon his giving a signal to his men, made an attack upon the Romans, who, notwithstanding the danger they had suffered in the river, when landed, bravely withstood the Britons; and having no other fence to trust to but their own courage, they made no small slaughter; but yet suffered a greater loss themselves, than that which they were able to give the enemy. For their number was considerably diminished by their loss in the river; whereas the Britons being hourly increased with new recruits, were three times their number, and by that advantage defeated them. Cæsar, seeing he could no longer maintain his ground, fled with a small body of men to his ships, and made the sea his safe retreat; and as the wind stood fair, he hoisted his sails, and steered to the shore of the Morini. From thence he repaired to a certain tower, which he had built at a place called Odnea, before this second expedition into Britain. For he durst not trust the fickleness of the Gauls, who he feared would fall upon him a second time, as we have said already they did before, after the first flight he was forced to make before the Britons. And on that account he had built this tower for a refuge to himself, that he might be able to maintain his ground against a rebellious people, if they should make insurrection against him. CHAP. VIII.--_Evelinus kills Hirelglas. Androgeus desires Cæsar's assistance against Cassibellaun._