.

The general arrangement of the campaign seems to have been settled
between Halleck and McClellan on the 5th of September. General
Sumner with the Second and Twelfth corps moved up the Potomac by way
of Tenallytown, Burnside with the First and Ninth corps moved to
Leesboro with a view to covering Baltimore, the front was explored
by the cavalry under Pleasonton, and the Sixth Corps, under
Franklin, constituted a reserve. [Footnote: Confusion in the numbers
of the First and Twelfth corps is found in the records and
dispatches, owing to the fact that in the Army of Virginia the corps
numbers were not those given them by the War Department. Sigel's,
properly the Eleventh Corps, had been called First of that army.
Banks's, properly Twelfth, had been called Second, and McDowell's,
properly First, had been called Third. In the Maryland campaign
Hooker was assigned to McDowell's, and it sometimes figures as
First, sometimes as Third; Mansfield was assigned to Banks's. The
proper designations after the consolidation were First and Twelfth.
Reno had been assigned to the First, but McClellan got authority to
change it, and gave it to Hooker, sending Reno back to the Ninth.
Official Records, vol. xix. pt. ii. pp. 197, 198, 279, 349.] The
preliminary movements occupied the 5th and 6th, but on the 7th the
positions were as I have stated them. The principal bodies were
designated, respectively, as right and left wings instead of armies.
The two corps from the Army of Virginia were separated, one being
assigned to the right wing under Burnside, and the other to the left
under Sumner.

CHAPTER XIII

SOUTH MOUNTAIN

March through Washington--Reporting to Burnside--The Ninth
Corps--Burnside's personal qualities--To Leesboro--Straggling--Lee's
army at Frederick--Our deliberate advance--Reno at New Market--The
march past--Reno and Hayes--Camp gossip--Occupation of
Frederick--Affair with Hampton's cavalry--Crossing Catoctin
Mountain--The valley and South Mountain--Lee's order found--Division
of his army--Jackson at Harper's Ferry--Supporting Pleasonton's
reconnoissance--Meeting Colonel Moor--An involuntary
warning--Kanawha Division's advance--Opening of the battle--Carrying
the mountain crest--The morning fight--Lull at noon--Arrival of
supports--Battle renewed--Final success--Death of Reno--Hooker's
battle on the right--His report--Burnside's comments--Franklin's
engagement at Crampton's Gap.

Late in the night of the