Warren and Ord fulfilled their instructions perfectly so far as making ready was concerned.  Burnside seemed to have paid no attention whatever to the instructions, and left all the obstruction in his own front for his troops to get over in the best way they could.  The four divisions of his corps were commanded by Generals Potter, Willcox, Ledlie and Ferrero.  The last was a colored division; and Burnside selected it to make the assault.  Meade interfered with this.  Burnside then took Ledlie’s division—­a worse selection than the first could have been.  In fact, Potter and Willcox were the only division commanders Burnside had who were equal to the occasion.  Ledlie besides being otherwise inefficient, proved also to possess disqualification less common among soldiers.

There was some delay about the explosion of the mine so that it did not go off until about five o’clock in the morning.  When it did explode it was very successful, making a crater twenty feet deep and something like a hundred feet in length.  Instantly one hundred and ten cannon and fifty mortars, which had been placed in the most commanding positions covering the ground to the right and left of where the troops were to enter the enemy’s lines, commenced playing.  Ledlie’s division marched into the crater immediately on the explosion, but most of the men stopped there in the absence of any one to give directions; their commander having found some safe retreat to get into before they started.  There was some delay on the left and right in advancing, but some of the troops did get in and turn to the right and left, carrying the rifle-pits as I expected they would do.

There had been great consternation in Petersburg, as we were well aware, about a rumored mine that we were going to explode.  They knew we were mining, and they had failed to cut our mine off by countermining, though Beauregard had taken the precaution to run up a line of intrenchments to the rear of that part of their line fronting where they could see that our men were at work.  We had learned through deserters who had come in that the people had very wild rumors about what was going on on our side.  They said that we had undermined the whole of Petersburg; that they were resting upon a slumbering volcano and did not know at what moment they might expect an eruption.  I somewhat based my calculations upon this state of feeling, and expected that when the mine was exploded the troops to the right and left would flee in all directions, and that our troops, if they moved promptly, could get in and strengthen themselves before the enemy had come to a realization of the true situation.  It was just as I expected it would be.  We could see the men running without any apparent object except to get away.  It was half an hour before musketry firing, to amount to anything, was opened upon our men in the crater.  It was an hour before the enemy got artillery up to play upon them; and it was nine o’clock before Lee got up reinforcements from his right to join in expelling our troops.