1. In approaching the enemy through a wooded or broken country,
skirmishers thrown out in advance, and on the flanks of the leading
column, are absolutely indispensable, in order to _reconnoitre the
ground_, and prevent a surprise.
2. Skirmishers _protect_ the main body, or any particular portion of it,
from attack while manoeuvring.
A regiment, or a brigade, in covered ground, whether the enemy be
visible or not, should never change its position in battle, or
manoeuvre, without the protection of a skirmishing line.
3. They furnish a screen, behind which the main body may _hide its
movements_, and be enabled to attack at an unexpected point.
4. Where a ravine, a wood, or other similar obstacle causes _a break in
our line of battle_, by occupying it with skirmishers we guard it
against penetration by the enemy, and connect the separated corps with
each other.
5. Skirmishers may be used to alarm the enemy at a point where he
expected no attack, and thus _create a diversion_.
6. By their attack at various points, they serve to _unmask the enemy's
position_.