B. 3.--Besides an unknown force of Gallic auxiliaries, its strength comprised four veteran legions, one (the Ninth _Hispanica_)[131] from the Danube frontier, the rest (Twentieth, Fourteenth, and Second) from the Rhine. This last, an "Augustan"[132] legion, was commanded by the future Emperor Vespasian--a connection destined to have an important influence on the _pronunciamento_ which, twenty-five years later, placed him on the throne.[133] As yet he was only a man of low family, whom favouritism was held to have hurried up the ladder of promotion more rapidly than his birth warranted.[134] Serving under him as Military Tribunes were his brother Sabinus and his son Titus; and in this British campaign all three Flavii are said to have distinguished themselves,[135] especially at the passage of an unnamed river, where the Britons made an obstinate stand. The ford was not passed till after three days' continuous fighting, of which the issue was finally decided by the "Celtic" auxiliaries swimming the stream higher up, and stampeding the chariot-horses tethered behind the British lines. B. 4.--What this stream may have been is a puzzle.[136] Dion Cassius brings it in after a victory over the sons of Cymbeline, Caradoc (or Caractacus, as historians commonly call him) and Togodumnus, wherein the latter was slain. And he adds that from its banks the Britons fell back upon their next line of defence, the _tide-way_ on the Thames. He tells us that, though tidal, the river was, at this point, fordable at low water for those who knew the shallows; and incidentally mentions that at no great distance there was even a bridge over it. But it was bordered by almost impassable[137] swamps. It must be remembered that before the canalizing of the Thames the influence of the tide was perceptible at least as high as Staines, where was also a crossing-place of immemorial antiquity. And hereabouts may very probably have been the key of the British position, a position so strong that it brought Plautius altogether to a standstill. Not till overwhelming reinforcements, including even an elephant corps, were summoned from Rome, with Claudius in person at their head, was a passage forced. The defence then, however, collapsed utterly, and within a fortnight of his landing, Claudius was able to re-embark for Rome, after taking Camelodune, and securing for the moment, without the loss of a man,[138] as it would seem, the nominal submission of the whole island, including even the Orkneys.[139] SECTION C. Claudius triumphs--Gladiatorial shows--Last stand of Britons--Gallantry of Titus--Ovation of Plautius--Distinctions bestowed--Triumphal arch--Commemorative coinage--Conciliatory policy--British worship of Claudius--Cogidubnus--Attitude of clans--Britain made Imperial Province.