one
o'clock
On the 2nd of May , the batteries opened on the wall of the fort , near its northwest angle ; and so heavy was their fire that , by the evening of the 3rd , a breach of sixty yards long was effected . General Harris determined to assault on the following day . General Baird , who had , for four years , been a prisoner in Seringapatam , volunteered to lead the assault ; and before daybreak 4,376 men took their places in the advance trenches , where they lay down . It was determined that the assault should not be made until one o'clock , at which time Tippoo 's troops , anticipating no attack , would be taking their food , and resting during the heat of the day . The troops who were to make the assault were divided into two columns which , after mounting the breach , were to turn right and left , fighting their way along the ramparts until they met at the other end . A powerful reserve , under Colonel Wellesley , was to support them after they had entered . When the signal was given , the troops leapt from the trenches and , covered by the fire of the artillery , which at the same moment opened on the ramparts , dashed across the river , scaled the breach , and , in six minutes from the firing of the signal gun , planted the British flag on its crest .