It may be that the enemy will occupy positions back from the city, out of range of the gunboats, so as to make it desirable to run past Grand Gulf and land at Rodney.  In case this should prove the plan, a signal will be arranged and you duly informed, when the transports are to start with this view.  Or, it may be expedient for the boats to run past, but not the men.  In this case, then, the transports would have to be brought back to where the men could land and move by forced marches to below Grand Gulf, re-embark rapidly and proceed to the latter place.  There will be required, then, three signals; one, to indicate that the transports can run down and debark the troops at Grand Gulf; one, that the transports can run by without the troops; and the last, that the transports can run by with the troops on board.

Should the men have to march, all baggage and artillery will be left to run the blockade.

If not already directed, require your men to keep three days’ rations in their haversacks, not to be touched until a movement commences.

U. S. GRANT, Major-General.

At 8 o’clock A.M., 29th, Porter made the attack with his entire strength present, eight gunboats.  For nearly five and a half hours the attack was kept up without silencing a single gun of the enemy.  All this time McClernand’s 10,000 men were huddled together on the transports in the stream ready to attempt a landing if signalled.  I occupied a tug from which I could see the effect of the battle on both sides, within range of the enemy’s guns; but a small tug, without armament, was not calculated to attract the fire of batteries while they were being assailed themselves.  About half-past one the fleet withdrew, seeing their efforts were entirely unavailing.  The enemy ceased firing as soon as we withdrew.  I immediately signalled the Admiral and went aboard his ship.  The navy lost in this engagement eighteen killed and fifty-six wounded.  A large proportion of these were of the crew of the flagship, and most of those from a single shell which penetrated the ship’s side and exploded between decks where the men were working their guns.  The sight of the mangled and dying men which met my eye as I boarded the ship was sickening.

Grand Gulf is on a high bluff where the river runs at the very foot of it.  It is as defensible upon its front as Vicksburg and, at that time, would have been just as impossible to capture by a front attack.  I therefore requested Porter to run the batteries with his fleet that night, and to take charge of the transports, all of which would be wanted below.

There is a long tongue of land from the Louisiana side extending towards Grand Gulf, made by the river running nearly east from about three miles above and nearly in the opposite direction from that point for about the same distance below.  The land was so low and wet that it would not have been practicable to march an army across but for a levee.  I had had this explored before, as well as the east bank below to ascertain if there was a possible point of debarkation north of Rodney.  It was found that the top of the levee afforded a good road to march upon.