CHAPTER VII.

EMPLOYMENT OF ARTILLERY IN WAR.

=140.= _General instructions._

1. F.S. Regs., Part I, lay down certain principles for the guidance of commanders in the combined employment of the various arms. A knowledge of these principles by artillery commanders is essential for effective co-operation.

2. The instructions contained in this chapter are based on those principles, and are intended further to assist artillery commanders in the solution of problems which will confront them on the field of battle and in training their commands on a uniform system.

=These principles are generally applicable to any force of artillery acting under an independent commander, whether his command is of a temporary nature or not.=

CHARACTERISTICS OF FIELD ARTILLERY.

=141.= _Field guns._

1. The principal characteristics of modern field guns are the flatness of the trajectory of their shell, the rapidity and accuracy of their fire and their power to deliver effective fire from concealed positions as well as from those in the open. Other characteristics are mobility, increased power of concealment, owing to the use of smokeless powder, and decreased vulnerability, due to the adoption of shields.

2. The effect of field guns is most fully developed against troops in the open, either in movement or stationary.

They may be used effectively against personnel in entrenchments, in buildings or behind gun shields. Against personnel protected by entrenchments the effect will be slight unless the defenders are compelled to man their entrenchments by the action of the other arms. Against buildings the effect is usually limited to the rooms facing the guns, as the projectiles are arrested by a second wall, and their destructive and incendiary effect is not great. The destructive effect of direct hits on artillery _matériel_ is considerable, but at long ranges this would entail a great expenditure of ammunition. (_See_ Sec. =114= (6).)

=142.= _Field howitzers._

1. Field howitzers by reason of their high explosive shell and the steep angle of descent of their shrapnel bullets are specially suited:--

i. To attack artillery personnel protected by shields. ii. To destroy artillery _matériel_. iii. To attack the defenders of entrenchments.