, and enabling additional Union brigades to join the
attacking column by a direct march from Centreville.

At noon, however, the attack came to a halt, partly through the fatigue
of the troops, partly because the advancing line, having swept the field
for nearly a mile, found itself in a valley, from which further progress
had to be made with all the advantage of the ground in favor of the
enemy. In the lull of the conflict which for a while ensued, the
Confederate commander, with little hope except to mitigate a defeat,
hurriedly concentrated his remaining artillery and supporting regiments
into a semicircular line of defense at the top of the hill that the
Federals would be obliged to mount, and kept them well concealed among
the young pines at the edge of the timber, with an open field in their
front.

Against this second position of the enemy, comprising twelve regiments,
twenty-two guns, and two companies of cavalry, McDowell advanced in the
afternoon with an attacking force of fourteen regiments, twenty-four
guns, and a single battalion of cavalry, but with all the advantages of
position against him. A fluctuating and intermitting attack resulted.
The nature of the ground rendered a combined advance impossible. The
Union brigades were sent forward and repulsed by piecemeal. A battery
was lost by mistaking a Confederate for a Union regiment. Even now the
victory seemed to vibrate, when a new flank attack by seven rebel
regiments, from an entirely unexpected direction, suddenly impressed the
Union troops with the belief that Johnston's army from Harper's Ferry
had reached the battle-field; and, demoralized by this belief, the Union
commands, by a common impulse, gave up the fight as lost, and half
marched, half ran from the field. Before reaching Centreville, the
retreat at one point degenerated into a downright panic among army
teamsters and a considerable crowd of miscellaneous camp-followers; and
here a charge or two by the Confederate cavalry companies captured
thirteen Union guns and quite a harvest of army wagons.

When the truth came to be known, it was found that through the want of
skill and courage on the part of General Patterson in his operations at
Harper's Ferry, General Johnston, with his whole Confederate army, had
been allowed to slip away; and so far from coming suddenly into the
battle of Bull Run, the bulk of them were already in Beauregard's camps
on Saturday, and performed the heaviest part o