The first step was to discover something about the town and its defences: how many men could be mustered on the walls, and what means the Knights had of providing against a long siege. For this purpose he despatched a Jewish physician greatly trusted by his father, to the island, with orders to pretend himself ready to become a Christian so as to find favour with the Grand Master of the Knights of St. John, and to lose no opportunity of making friends with the people by trying to cure their sick. These instructions were faithfully carried out by the Jew, who sent word to the Sultan that an important part of one of the city walls was being rebuilt, and that if an army could be landed before the work could be completed, the men would easily be able to enter the breach. Now the Jew, of course, was fulfilling the task given him, and was risking his own neck in the accomplishment of it. But what can be said of the treachery of one of the Knights themselves who out of jealousy had bidden Solyman to besiege the town? This man, Sir Andrew de Merall, was a Portuguese and so highly thought of among his fellows that he had been named Chancellor of the Order. He expected, however, to be the next Grand Master, and when, on the death of Fabrice of Cacetto, Sir Philip de Villiers was chosen in his place, de Merall's rage at being passed over was such that he could not control himself. The Knights did not pay much heed to his words; it was natural, they thought, that he should be disappointed, but he would soon calm down again. And so de Merall did, to all outward appearance, and no one guessed how black were his thoughts. A pretext for his treason was soon found: it was easy for him to send over a Turkish prisoner to Constantinople, on the plea of the man raising money for his ransom, and instructing the Turk beforehand exactly what he was to tell the Sultan as to the condition of the city. 'He will never find a better time,' said the traitor, 'seeing that the wall is now partly down and there is mischief among some Italian Knights. As to help from without, the Christian princes are busy warring each upon the other, and, if this should last, the town will be his without fail,' which thing came to pass.