Apr 9 1862, Wrote Gen. Halleck, “There is little doubt but that the enemy intend concentrating upon the railroad at and near Corinth all the force possible, leaving many points heretofore guarded entirely without troops. I learn this through Southern papers and from a spy who was in Corinth after the rebel army left.
“They have sent steamers up White River to bring down Van Dorn’s and Price’s commands. They are also bringing forces from the East. Prisoners also confirm this information.
“I do not like to suggest, but it appears to me that it would be demoralizing upon our troops here to be forced to retire upon the opposite bank of the river and unsafe to remain on this many weeks without large re-enforcements. The attack on Sunday was made, according to the best evidence I have, by one hundred and sixty-two regiments. Of these many were lost by killed, wounded, and desertion. They are at present very badly crippled, and cannot recover under two or three weeks. Of this matter you may be better able to judge than I am.
“There was one act of the rebels on the battle-field on Sunday which cannot be justified. I have the evidence of officers who say, and could not be deceived, that a brigade dressed in black, and with the Union flag unfurled, passed through an open field in front of one of our batteries, thereby regaining a position that could not otherwise have been attained without loss of life.”
The Papers of Ulysses S Grant, Vol 5, p 31-2
O.R., I, x, part 2, p 99-100