The discovery that the cannon were immovable, decided Napoleon in his dispositions for the battle, and he gave orders that his army should move across to his right, and should thus be concentrated for the attack upon the Mamelukes and Arabs. Mourad Bey, seeing Napoleon's object, at once ordered two-thirds of his cavalry to charge the French while they were in motion, while the others were to remain near the entrenched camp. So rapidly did they sweep down, that the French squares fell into some confusion, and Desaix, with his division, which formed the head of the column, had difficulty in maintaining themselves, their ranks being somewhat broken by a grove of palm-trees through which they were passing. They, however, received the Mamelukes with so terrible a fire of musketry and grape-shot that the charge was not pressed home. The Mamelukes, however, fought with desperate courage, sweeping round the French squares, and even endeavouring to back their horses into the line of bayonets, in hopes of breaking the wall of steel.