Sorties of this kind may sometimes be profitably made against the flanks of the attacking force, or against isolated batteries, even when a general attack cannot be made. Opportunities for their use should not be neglected.
CHAPTER II.
SIEGE OR ATTACK BY REGULAR APPROACHES.
PRELIMINARY CONSIDERATIONS, DEFINITIONS, ETC.
9. By a regular siege is meant a systematic and more or less deliberate attack upon a fortified place, in which the besieger aims to invest the place and capture its fortifications in succession by regular approaches, beginning with the most advanced and ending only with the reduction of the innermost keep and the surrender of the garrison.
The successive steps of a siege are usually the following:
The investment.
The artillery attack.
The construction of parallels and approaches.
Breaching by artillery or mines.