. On this I sent to Burnside the request
that Willcox's division be sent over, with an ammunition train, and
that Sturgis's division be replaced by the fresh troops, remaining,
however, on the west side of the stream as support to the others.
This was done as rapidly as was practicable, where everything had to
pass down the steep hill-road and through so narrow a defile as the
bridge. [Footnote: As a mode of ready reckoning, it is usual to
assume that a division requires an hour to march past a given point
by the flank. With the crossing of an ammunition train, the interval
of time is more than accounted for.] Still, it was three o'clock
before these changes and preparations could be made. Burnside had
personally striven to hasten them, and had come over to the west
bank to consult and to hurry matters, and took his share of personal
peril, for he came at a time when the ammunition wagons were
delivering cartridges, and the road at the end of the bridge where
they were was in the range of the enemy's constant and accurate
fire. It is proper to mention this because it has been said that he
did not cross the stream. The criticisms made by McClellan as to the
time occupied in these changes and movements will not seem forcible
if one will compare them with any similar movements on the field;
such as Mansfield's to support Hooker, or Sumner's or Franklin's to
reach the scene of action. About this, however, there is fair room
for difference of opinion: what I personally know is that it would
have been folly to advance again before Willcox had relieved
Sturgis, and that as soon as the fresh troops reported and could be
put in line, the order to advance was given. McClellan is in accord
with all other witnesses in declaring that when the movement began,
the conduct of the troops was gallant beyond criticism.

Willcox's division formed the right, Christ's brigade being north,
and Welsh's brigade south of the road leading from the bridge to
Sharpsburg. Crook's brigade of the Kanawha division supported
Willcox. Rodman's division formed on the left, Harland's brigade
having the position on the flank, and Fairchild's uniting with
Willcox at the centre. Scammon's brigade was the reserve for Rodman
at the extreme left. [Footnote: Official Records, vol. xix. pt. i.
pp. 425, 430.] Sturgis's division remained and held the crest of the
hill above the bridge. About half of the batteries of the divisions
accompanied the movement, the rest