ch:_ In close order, execute _squads right about_.

_Halt._

_Assemble, march._

The following bugle signals may be used on the battle field:

_Fix bayonets._

_Charge._

_Assemble, march._

These signals are used only when intended for the entire firing line;
hence they can be authorized only by the commander of a unit (for
example, a regiment or brigade) which occupies a distinct section of
the battle field. Exception: _Fix bayonet_. (See par. 318.)

The following bugle signals are used in exceptional cases on the
battle field. Their principal uses are in field exercises and practice
firing.

_Commence firing:_ Officers charged with fire direction and control
open fire as soon as practicable. When given to a firing line, the
signal is equivalent to _fire at will_.

_Cease firing:_ All parts of the line execute _cease firing_ at once.

These signals are not used by units smaller than a regiment, except
when such unit is independent or detached from its regiment.

_Whistle Signals._

42. _Attention to orders._ A _short blast_ of the whistle. This signal
is used on the march or in combat when necessary to fix the attention
of troops, or of their commanders or leaders, preparatory to giving
commands, orders, or signals.

When the firing line is firing, each squad leader suspends firing and
fixes his attention at a _short blast_ of his platoon leader's
whistle. The platoon leader's subsequent commands or signals are
repeated and enforced by the squad leader. If a squad leader's
attention is attracted by a whistle other than that of his platoon
leader, or if there are no orders or commands to convey to his squad
he resumes firing at once.

_Suspend firing._ A _long blast_ of the whistle.

All other whistle signals are prohibited.

(_C.I.D.R., No. 15._)

_Arm Signals._

43. The following arm signals are prescribed. In making signals either
arm may be used. Officers who receive signals on the firing line
"repeat back" at once to prevent misunderstanding.

_Forward, march._ Carry the hand to the shoulder; straighten and hold
the arm horizontally, thrusting it in direction of march.

This signal is also used to execute quick time from double time.

_Halt._ Carry the hand to the shoulder; thrust the hand upward and
hold the arm vertically.

_Double time, march._ Carry the hand to the shoulder; rapidly thrust
the hand upward the full extent of the arm several times.

_Squads right, march._ Rai