you, but not on the ridge referred to. You know or believe none
of your patrols are out in that neighborhood. In this case you should
realize instantly, without any order, that your mission had changed
and you should hasten to discover the size and position of this new
enemy and send the information back to your chief, first notifying him
of your intended change of direction.

Never forget your mission in the excitement of leading your own little
force.

=982. Absence of the Enemy.= It is frequently just as important to
send a message to your chief that the enemy is not in a certain
locality as it is to report his actual whereabouts. You must determine
from your mission when this is the case. For example, if you were
ordered "To patrol beyond that woods and see if any hostile columns
are moving in that direction," and on reaching the far side of the
woods you had a good view of the country for some distance beyond, it
would be very important to send a message back telling your chief that
you could see, say, one-half mile beyond the woods and there was no
enemy in sight. This information would be of the greatest importance
to him. He might feel free to move troops immediately from that
vicinity to some more dangerous place. You would then continue your
reconnaissance further to the front.

Suggestions for Gaining Information About the Enemy

=983. Enemy on the March.= (=a=) The patrol should observe the march
of the column from a concealed position that hostile patrols or
flankers are not apt to search (avoid conspicuous places). Always try
to discover if one hostile detachment is followed by another--if what
can be seen appears to be an advance guard of a larger body not yet in
view. The distance between the detachments, their relative size, etc.,
is always important.

(=b=) =Estimating Strength of Column.= The strength of a column may be
estimated from the length of time it takes to pass a selected point.
As infantry in column of squads occupies half a yard per man, cavalry
one yard per horse and artillery in single file twenty yards per gun
or caisson (ammunition wagon), a selected point would be passed in one
minute by 175 infantry; 110 cavalry (at a walk); 200 cavalry at a trot
and 5 guns or caissons. If marching in columns of twos, take one-half
of the above figures.

(=c=) =Dust.= The direction of march, strength and composition
(infantry, cavalry or artillery) of a column can be closely estimated
from