ho had defeated it on December 13, 1862. Burnside withdrew (December
15, 1862) across the Potomac to Stafford Heights with the whole of his
army, under cover of a heavy storm. If special orders had been given
by the Outpost commanders for constant and vigorous patrolling, and if
scouts had been instructed to penetrate the Federal lines from time to
time at all risks, Burnside could have been attacked at a disadvantage
while on the move and should have been driven into the Potomac. {140}
During the battle itself a Confederate Brigade was surprised in its own
front line through failure to patrol a triangular wood which jutted out
in front of the position and screened the brigade on the left with
which touch was not maintained. At all times of action with enemy
forces all ground to the front or flank must be kept under close
observation, or surprise may lead to disaster.

{141}

TACTICAL RECONNAISSANCE

Reconnaissance during battle has been dealt with under "Influences on
the Battle" and in other lectures, and owing to the close connection
between the two subjects a number of points concerning reconnaissance
in general have been noted in dealing with Protection. It has also
been seen that observation by Aircraft, Patrols, and Sentries is
essential to Protection both in Position Warfare and the War of
Manoeuvre, and that Reconnaissance is the essence of Protection. There
remain, however, two forms of Reconnaissance that have not yet been
considered, namely: the Reconnaissance of a Position with a view to
attacking it, and the Reconnaissance of an unoccupied position with a
view to occupying it for defence.

RECONNAISSANCE FOR ATTACK.--The first of these is the constant duty of
all commanders in the line during Position Warfare, and it is carried
out by Patrols and Raiding Parties, who provide information which
supplements the photographs and reports of the Air Service, and enables
a commander to arrive at a decision. In a War of Manoeuvre
reconnaissance by the Air Service is equally important, and it is
supplemented by the work of the Patrols of the Advanced Guard, but
principally by that of specially selected Intelligence Officers,
working in conjunction with, or independent of, the Vanguard. Such
officers would be in possession of information which it might not be
possible to reveal to the commander of the Patrols of the Vanguard, and
their special training would give an added value to their report. The