The French fleet was anchored along the south shore of the river-mouth, sterns to the land, its left towards the river-mouth, its right towards the town of Sluys. The vessel on the extreme left was an English ship of large size, the "Great Cristopher," captured in the Channel in the first days of the war. The ships were grouped in three divisions--left, centre, and right. Kiriet and Bahuchet adopted the same plan of battle that King Olaf had used at Svold. The ships in each of the three divisions were lashed together side by side, so that they could only be boarded by the high narrow bows, and there was an addition to the Norse plan, for inboard across the bows barricades had been erected formed of oars, spars, and planking, fastened across the forecastle decks. Behind these barriers archers and Genoese cross-bowmen were posted. There was a second line of archers in the fighting-tops, for since the times of Norse warfare the masts had become heavier, and now supported above the crossyard a kind of crow's nest where two or three bowmen could be stationed, with shields hung round them as a parapet. The fleet thus was converted into a series of three long, narrow floating forts. It was an intelligible plan of defence for a weak fleet against a strong one, but a hopeless plan for an armament strong enough to have met its opponents on the open sea, ship to ship. At Svold, Erik Jarl had shown that such an array could be destroyed piecemeal if assailed on an exposed flank, and at Sluys the left, where the "Great Cristopher" lay to seaward, positively invited such an attack. King Edward saw his advantage as soon as his knights came back from their adventurous ride and told him what they had seen, and he arranged his plans accordingly. His great ships were to lead the attack, and concentrate their efforts on the left of the French line. The rest were to pass inside them and engage the enemy in front, on the left, and centre. The enemy had by tying up his ships made it impossible to come to the rescue of the left, even if the narrow waters of the estuary would have allowed him to deploy his force into line. The English would have, and could not fail to keep, a local superiority from the very outset on the left of the enemy, and once it came to close quarters they would clear the French and Genoese decks from end to end of the line, taking ship after ship. While the attack developed the English archers would prepare the way for it by thinning the ranks of their enemies on the ships in the centre and then on the right.