Several times they found their way of retreat blocked by boats that had come down through side channels, and had to fight their way back with great loss and difficulty. After maintaining the struggle for four days, and suffering a loss even greater than that they had incurred in their first attack, the Romans again drew off and ascended the river. The Fenmen had joined the Iceni in repelling the attack. The portion of the swamp they inhabited was not far away, and they felt that they too were threatened by the Roman advance. They had therefore rejoined the Iceni, although for some time they had kept themselves aloof from them, owing to quarrels that had arisen because, as they asserted, some of the Iceni had entered their district and carried off the birds from their traps. Beric had done all in his power to allay this feeling, recompensing them for the losses they declared they had suffered, and bestowing many presents upon them. He and Aska often talked the matter over, and agreed that their greatest danger was from the Fenmen. "They view us as intruders in their country," Aska said, "and doubtless consider that in time we shall become their masters. Should they turn against us they could lead the Romans direct to our islands, and if these were lost all would be lost." "If you fear that, Aska," Boduoc, who was present, said, "we had better kill the little wretches at once." "No, no Boduoc," Beric said. "We have nothing against them at present, and we should be undeserving of the protection of the gods were we to act towards them as the Romans act towards us. Moreover, such an attempt would only bring about what we fear. Some of them, knowing their way as they do through the marshes, would be sure to make their escape, and these would bring the Romans down upon us. Even did we slay all this tribe here, the Fenmen in the north would seek to avenge their kinsmen, and would invite the Romans to their aid. No, we must speak the Fenmen fair, avoid all cause of quarrel, do all we can to win their goodwill, and show them that they have nothing to fear from us. Still, we must always be on guard against treachery. Night and day a watch must be set at the mouths of all the channels by which they might penetrate in this direction."