eneral Lee's orders of march for the army, in which his whole plan
was revealed. General McClellan had therein the unmistakable evidence
of his opponent's intentions, and from that moment his advance was as
rapid as before it had been deliberate.

The result of this fortunate discovery was speedily seen. General Lee,
while moving steadily toward Hagerstown, was suddenly compelled to
turn his attention to the mountain-passes in his rear. It had not been
the intention of Lee to oppose the passage of the enemy through the
South Mountain, as he desired to draw General McClellan as far as
possible from his base, but the delay in the fall of Harper's
Ferry now made this necessary. It was essential to defend the
mountain-defiles in order to insure the safety of the Confederate
troops at Harper's Ferry; and Lee accordingly directed General
D.H. Hill to oppose the passage of the enemy at Boonsboro Gap, and
Longstreet was sent from Hagerstown to support him.

An obstinate struggle now ensued for the possession of the main South
Mountain Gap, near Boonsboro, and the roar of Jackson's artillery from
Harper's Ferry must have prompted the assailants to determined efforts
to force the passage. The battle continued until night (September
14th), and resulted in heavy loss on both sides, the brave General
Reno, of the United States army, among others, losing his life.
Darkness put an end to the action, the Federal forces not having
succeeded in passing the Gap; but, learning that a column of the enemy
had crossed below and threatened him with an attack in flank, General
Lee determined to retire in the direction of Sharpsburg, where Jackson
and the forces cooeperating with him could join the main body of the
army. This movement was effected without difficulty, and Lee notices
the skill and efficiency of General Fitz Lee in covering the rear with
his cavalry. The Federal army failed to press forward as rapidly as
it is now obvious it should have done. The head of the column did
not appear west of the mountain until eight o'clock in the morning
(September 15th), and, nearly at the same moment ("the attack began at
dawn; in about two hours the garrison surrendered," says General Lee),
Harper's Ferry yielded to Jackson.

Fast-riding couriers brought the welcome intelligence of Jackson's
success to General Lee, as the latter was approaching Sharpsburg,
and official information speedily came that the result had been
the capture of more than