Cæsar, however, while the vessels were coming up, ordered Silius, his lieutenant-general, to make an inroad on the Chatti with a flying column. He himself, on hearing that a fort on the river Luppia was being besieged, led six legions to the spot. Silius owing to sudden rains did nothing but carry off a small booty, and the wife and daughter of Arpus, the chief of the Chatti. And Cæsar had no opportunity of fighting given him by the besiegers, who dispersed on the rumour of his advance. They had, however, destroyed the barrow lately raised in memory of Varus's legions, and the old altar of Drusus. The prince restored the altar, and himself with his legions celebrated funeral games in his father's honour. To raise a new barrow was not thought necessary. All the country between the fort Aliso and the Rhine was thoroughly secured by new barriers and earthworks.