long marches to halt for three or four hours during the
hottest part of the day and finish the march in the late afternoon or
early evening. As a general proposition, however, it is inadvisable to
arrive at a strange place after nightfall or even late in the
afternoon.

=1223. Crossing bridges and fords.= When a cause of delay,--for
example, a damaged bridge,--is encountered, the troops in rear are
notified of the minimum length of the delay; they then conduct
themselves as at regular halts.

In ascending or descending slopes, crossing streams or other
obstacles, or passing through defiles requiring a reduction of front,
every precaution is taken to prevent interruption of the march of the
troops in rear. If the distances are not sufficient to prevent check,
units are allowed to overlap; if necessary, streams are crossed at two
or more places at the same time; in passing through short defiles the
pace is accelerated and the exit cleared at once.

If a company unit is delayed while crossing an obstacle, the head
slackens the pace or halts until all of that unit has passed; it then
resumes its place in the column, increasing the pace, if necessary.

Before attempting to cross with bodies of troops, careful examination
is made of fords, boggy places, bridges of doubtful character, ice,
etc., as the case may be.

Troops must never cross a bridge in cadence,--that is, the men must
not be in step.

In fording a deep stream with a swift current, the men cross on as
broad a front as possible, marching abreast and holding hands. They
should not look at the water, but at the opposite shore. If the ford
is wide enough, mounted troops may cross at the same time on the
upstream side, thus breaking the force of the current.

Fords that are at all difficult delay long columns unless the troops
cross at several places at once.

=1224. Straggling and elongation of column.= The marching efficiency
of an organization is judged by the amount of straggling and
elongation of the column and the condition of the men at the end of
the march.

An officer of each company marches in its rear to prevent undue
elongation and straggling. If there be only one officer with a
company, the first sergeant performs this duty.

No man should leave the ranks without permission. If necessary for a
man to fall out on account of sickness, he should be given a permit to
do so by the company commander or the officer at the rear of the
company. This