Plautius had therefore hard work to discover his foe, but he did at last come to close quarters, first with Caratacus and then with Togodumnus, both of whom he overcame. Either now or in the following operations, Togodumnus perished, but his brother survived to be for many years a thorn in the side of the Roman general. A British tribe named the Boduni, of whose geographical position we are ignorant, but who were subjects of the Catuvellauni, came in and offered their submission. Plautius left a garrison among them and marching forward arrived at the banks of a river, possibly the Medway, which the barbarians fondly hoped could not be traversed without a bridge. The Roman general, however, had in his army many Gaulish soldiers, probably those dwelling near the mouths of the Rhine and the Waal, who were accustomed to swim with all their armour on across the swiftest streams. These men, at the word of command, plunged into the river, swam across, attacked the dismayed and carelessly encamped barbarians, and directing their weapons especially against the horses harnessed to the chariots made the usual cavalry tactics of the Britons impossible. The young Vespasian (future emperor, and conqueror of the Jews) and his brother Sabinus were ordered to lead some more troops across the stream and complete the victory, which they did, slaying multitudes of the barbarians. Still the Britons made a stubborn resistance, till at last an officer named Cnæus Hosidius Geta, a kind of Roman paladin who had before this done knightly deeds in fighting against the Moors, almost single-handed and at the imminent risk of capture, achieved a victory which compelled them to retire, and for which he received the honours of a triumph. Hereupon the Britons withdrew behind the Thames, at that time and place a broad and shallow stream flowing wide over the marshes of Essex. The barbarians knew well its deeps and its shallows, and could find their way across it in safety. Not so the Romans, who suffered severe loss in attempting to follow them. As a mere question of strategy Plautius could probably have marched up the stream and crossed it at some narrower part of its course. He determined, however, to reserve this achievement for the emperor who had apparently already arranged to visit Britain and pluck the laurels planted for him by his general. Claudius prepared reinforcements, including, we are told, a number of elephants (not very serviceable, one would have thought, in the Essex marshes), sailed from his own port of Ostia to Marseilles, then travelled, chiefly by water, up and down the great rivers of Gaul, arrived at the camp of Plautius, crossed the Thames, the proper appliances having no doubt been prepared by the loyal general, and then marched on Camulodunum, which he took, making the palace of Cunobelinus his own. The fall of the powerful kingdom of the Catuvellauni brought with it the submission, voluntary or forced, of many neighbouring tribes.