Then they winged their ships with their sails and boldly sailed over to Illyria. But as the south wind was blowing very strongly it prevented their landing at Dyrrachium, and compelled them to sail past the coast of Dyrrachium. and run into Valona. There they brought their huge merchant-ships to land and thence conveyed to Bohemund the large supplies of horse and foot-soldiers they had carried over, and all the wants of life. And from these they set up a number of stalls where the Franks could buy in abundance everything for their maintenance.”
The Emperor was very enraged and censured Isaac severely and by threatening him in case he did not do better he succeeded in making him keep an untiring watch. But Contostephanus did not accomplish anything as he intended (for though he endeavoured more than once to intercept the ships sailing to Illyria he failed in his object; for he held the middle of the straits and when he saw the Franks sailing along under a favourable wind with all their sails set and going at a great pace he was quite unable to fight against the Franks and the wind at the same time, as the breeze was contrary and not even Heracles could fight against two, they say; and thus he was driven backwards by the violence of the wind). At this news the Emperor was cut to the heart, for he recognized that Contostephanus did not station his fleet in the right spot and consequently the south winds which favoured the Franks’ crossing hindered him.
He therefore made a map of the coast of Lombardy and of Illyria, putting in the harbours on either side, and sent it to Contostephanus, and explained to him by letter where he ought to post his ships and from which place he could start with a favouring wind against the Franks who were crossing. He again encouraged Contostephanus and urged him to tackle the work. So Isaac took heart and went and anchored his ships where the Emperor had advised him to. Then he waited for his opportunity and one day when the men from Lombardy were sailing across to Illyria with a quantity of stores, and the right wind was blowing, he caught them in the middle of the strait and set fire to some of the freight-ships, while sending the greater number to the bottom, crews and all.
Duke of Dyrrachium
Before he heard of this but had his mind full of what Landulph and even the Duke of Dyrrachium had written, the Emperor changed his mind and sent for Marianus Mavrocatacalon (who was mentioned above) and appointed him Duke of the Fleet and entrusted the Petroula business to another man. So Marianus went off and by sheer good luck at once ran into pirate- and freight-swps sailing from Lombardy to Bohemund and captured fhem and they were all full of provisions. And for the future he was a sleepless guardian of the straits between Lombardy and Illyria, and did not allow any Franks at all to sail across to Dyrrachium.
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