Pemberton says in his report: 

“If it should be asked why the 4th of July was selected as the day for surrender, the answer is obvious.  I believed that upon that day I should obtain better terms.  Well aware of the vanity of our foe, I knew they would attach vast importance to the entrance on the 4th of July into the stronghold of the great river, and that, to gratify their national vanity, they would yield then what could not be extorted from them at any other time.”

This does not support my view of his reasons for selecting the day he did for surrendering.  But it must be recollected that his first letter asking terms was received about 10 o’clock A.M., July 3d.  It then could hardly be expected that it would take twenty-four hours to effect a surrender.  He knew that Johnston was in our rear for the purpose of raising the siege, and he naturally would want to hold out as long as he could.  He knew his men would not resist an assault, and one was expected on the fourth.  In our interview he told me he had rations enough to hold out for some time—­my recollection is two weeks.  It was this statement that induced me to insert in the terms that he was to draw rations for his men from his own supplies.

On the 4th of July General Holmes, with an army of eight or nine thousand men belonging to the trans-Mississippi department, made an attack upon Helena, Arkansas.  He was totally defeated by General Prentiss, who was holding Helena with less than forty-two hundred soldiers.  Holmes reported his loss at 1,636, of which 173 were killed; but as Prentiss buried 400, Holmes evidently understated his losses.  The Union loss was 57 killed, 127 wounded, and between 30 and 40 missing.  This was the last effort on the part of the Confederacy to raise the siege of Vicksburg.

On the third, as soon as negotiations were commenced, I notified Sherman and directed him to be ready to take the offensive against Johnston, drive him out of the State and destroy his army if he could.  Steele and Ord were directed at the same time to be in readiness to join Sherman as soon as the surrender took place.  Of this Sherman was notified.

I rode into Vicksburg with the troops, and went to the river to exchange congratulations with the navy upon our joint victory.  At that time I found that many of the citizens had been living under ground.  The ridges upon which Vicksburg is built, and those back to the Big Black, are composed of a deep yellow clay of great tenacity.  Where roads and streets are cut through, perpendicular banks are left and stand as well as if composed of stone.  The magazines of the enemy were made by running passage-ways into this clay at places where there were deep cuts.  Many citizens secured places of safety for their families by carving out rooms in these embankments.  A door-way in these cases would be cut in a high bank, starting from the level of the road or street, and after running in a few feet a room of the size required was carved out of the clay, the dirt being removed by the door-way.  In some instances I saw where two rooms were cut out, for a single family, with a door-way in the clay wall separating them.  Some of these were carpeted and furnished with considerable elaboration.  In these the occupants were fully secure from the shells of the navy, which were dropped into the city night and dav without intermission.