rders of the
leaders and careful observation of the enemy; an increase of fire when
the target is favorable, and a cessation of fire when the enemy
disappears; economy of ammunition.

=1407. To train and instruct the commander to use the unit with
intelligence and efficiency.= In order to handle the unit with
intelligence and efficiency, utilizing to the greatest extent possible
the power of all the rifles under his command, not only must the
commander be able to control the unit, having it respond at once to
his every command, but he must also know tactics, and be thoroughly
familiar with the technical principles of infantry fire.

=1408. Combat exercises.= A combat exercise consists of the
application of tactical principles to certain assumed battle
situation, in the execution of which are employed the appropriate
formations and movements of close and extended order drill, and in
which, as a rule, ball cartridges are used in firing at the targets.

By means of combat exercises, the unit commanders are trained and
instructed in applying tactical principles, in controlling and
directing the fire of their units and the men are trained and
instructed in fire discipline.

The tactical principles applicable to combat exercises are covered in
the Infantry Drill Regulations, under the headings of "_Fire_" and
"_Combat_."

=1409. Technical principles of firing.= The technical principles of
firing are given in detail in the Small-Arms Firing Manual, a summary
of which is given below under the headings of, _The Effect of Fire_,
_The Influence of the Ground_, and _The Adjustment of Fire_.

The Effect of Fire

=1410. Ballistic qualities of the rifle.= The accuracy of a rifle, the
flatness of its trajectory, and its disabling power,--that is, the
power it has to disable the enemy,--are called its _ballistic
qualities_.

The accuracy of the U. S. Springfield rifle, caliber .30, model of
1903, is very high,--probably superior to that of any other military
rifle.

The flatness of trajectory is dependent upon the muzzle velocity, and,
to some extent, upon the form of the bullet. Our bullet is pointed and
the muzzle velocity is 2700 feet per second, which is a very high
muzzle velocity.

Two rifles of different type may be equally accurate, but the accuracy
of the one having the flatter trajectory will, naturally, be less
affected by slight errors in sight setting.

Again, another advantage of the rifle with the flatte