Christian army presumed to insult his capital.  The menaces and vain bravadoes of the Prince of Tunis effected no change in the plans of the crusade; the Moors, besides, inspired no fear, and they themselves could not conceal the terror which the sight only of the Christians created in them.  Not daring to face their enemy, their scattered bands sometimes hovered around the Christian army, seeking to surprise any stragglers from the camp; and at others, uniting together, they poured down toward the advanced posts, launched a few arrows, showed their naked swords, and then depended upon the swiftness of their horses to secure them from the pursuit of the Christians.  They not unfrequently had recourse to treachery; three hundred of them came into the camp of the crusaders, and said they wished to embrace the Christian faith, and a hundred more followed them announcing the same intention.  After being received with open arms, they waited for what they deemed a favorable opportunity, and fell upon a body of the Christians, sword in hand; but being overwhelmed by numbers, most of them were killed, and the rest were allowed to escape.  Three of the principals fell on their knees and implored the compassion of their leaders.  The contempt the Franks had for such enemies obtained their pardon, and they were driven out of the camp.  At length the Mussulman army, now emboldened by the inaction of the Christians, presented itself several times on the plain.  Nothing would have been more easy than to attack and conquer it; but Louis had resolved to act upon the defensive, and to await the arrival of the King of Sicily, before beginning the war—­a fatal resolution, which ruined everything.  The Sicilian monarch, who had advised this ill-starred expedition, was destined to complete, by his delays, the evil he had begun by his counsels.  The Mussulmans flocked from all parts of Africa to defend the cause of Islamism against the Christians.  Preparations were carried on in Egypt to meet the invasion of the Franks; and in the month of August, Beibars announced by messengers that he was about to march to the assistance of Tunis.  The troops which the Sultan of Cairo maintained in the province of Barca received orders to set forward.  Thus the Moorish army was about to become formidable; but it was not this host of Saracens that the crusaders had most to dread.  Other dangers, other misfortunes, threatened them:  the Christian army wanted water; they had none but salted provisions; the soldiers could not endure the climate of Africa; winds constantly prevailed, which, coming from the torrid zone, appeared to the Europeans to be the breath of a devouring fire.  The Saracens upon the neighboring mountains raised the sand with certain instruments made for the purpose, and the dust was carried by the wind in burning clouds down upon the plain upon which the Christians were encamped.  At last, dysentery, that fatal malady of warm climates, began to commit frightful ravages among the troops; and the plague, which appears to be born of itself upon this burning, arid sand, spread its dire contagion through the Christian army.