rampart around them to preserve them from the attacks of the Britons, and leaving Labienus to collect fresh ships in Gaul, at once placed himself at the head of his legions.[432] [Sidenote: Violent storm and great loss of ships.] The British force having, however, gathered strength in the interval, now assumed a more threatening aspect; as Cassivelaunus, king of Hertfordshire and Middlesex, having triumphed in the wars in which he had been engaged at the time of Cæsar’s first invasion, now claimed dominion over the whole of the south-east of England, and was, therefore, able to oppose the new assault on Britain with a vast army, aided, it is said, with no less than four thousand chariots.[433] [Sidenote: Final action on the banks of the Thames.] But though some of the encounters were at first of doubtful success, the steady discipline of the Romans forced back the hosts of Cassivelaunus, and Cæsar apparently followed his retreating forces, first, in a north-westerly, and then in a direction due north, till they arrived at the banks of the Thames, a little to the west of Walton bridge. Here Cassivelaunus resolved to resist the further progress of Cæsar,[434] but was defeated in a well contested action, which rendered any further struggle against the Romans in that part, at least, of England, hopeless. [Sidenote: Cæsar makes terms with the Britons, and re-embarks his legions.] The legions of Cæsar had suffered so severely in this campaign, that he was equally glad with the native princes to enter into negotiations for peace; and, on the conclusion of these, he withdrew his army to Gaul, in little more than two months after his disembarkation at Lymne. As his homeward journey across the Channel lasted but eight hours, he must have had the wind in his favour. [Sidenote: Advantages derived by the Britons from their intercourse with the Romans.]