The bulk of the prisoners were taken from the Army of the Potomac. For
this there were two reasons: First, that there were many more men in that
Army than in any other; and second, that the entanglement in the dense
thickets and shrubbery of the Wilderness enabled both sides to capture
great numbers of the other's men. Grant lost in prisoners from May 5 to
May 31, seven thousand four hundred and fifty; he probably captured
two-thirds of that number from the Johnnies.

Wirz's headquarters were established in a large log house which had been
built in the fort a little distant from the southeast corner of the
prison. Every day--and sometimes twice or thrice a day--we would see
great squads of prisoners marched up to these headquarters, where they
would be searched, their names entered upon the prison records, by clerks
(detailed prisoners; few Rebels had the requisite clerical skill) and
then be marched into the prison. As they entered, the Rebel guards would
stand to arms. The infantry would be in line of battle, the cavalry
mounted, and the artillerymen standing by their guns, ready to open at
the instant with grape and canister.

The disparity between the number coming in from the Army of the Potomac
and Western armies was so great, that we Westerners began to take some
advantage of it. If we saw a squad of one hundred and fifty or
thereabouts at the headquarters, we felt pretty certain they were from
Sherman, and gathered to meet them, and learn the news from our friends.
If there were from five hundred to two thousand we knew they were from
the Army of the Potomac, and there were none of our comrades among them.
There were three exceptions to this rule while we were in Andersonville.
The first was in June, when the drunken and incompetent Sturgis (now
Colonel of the Seventh United States Cavalry) shamefully sacrificed a