This conclusion, which has been drawn from attacks on field-works, is still more positive in regard to attack upon works of strong profile protected by deep ditches and other obstacles.
DISPOSITIONS FOR AN ASSAULT.
5. When an assault is ordered the tactical dispositions must be so made as to keep the fire of the defence down to its lowest possible limit, until the assailant can close in with the bayonet.
With this end in view, batteries are established sweeping the lines; the assaulting columns, well supplied with ammunition, are formed where protected from fire; working parties are arranged and provided with such tools and appliances as are necessary for removing or overcoming obstacles; and all preparations are made for simultaneous action by the entire force.
It is manifest that to silence the fire of the work the attack must have a marked preponderance of artillery arranged both for enfilade and front fire upon the front of attack and the collateral works; and that the batteries must be established, the fire opened, and the guns of the defence silenced before the assault is made; and that this fire must continue until the assaulting troops are so near the work as to necessitate its discontinuance to avoid injury to them.
The working parties—carrying axes, saws, crowbars, and similar tools which are needed for removing the existing obstacles; explosives for blowing down gates, barriers, etc.; fascines, gabions, hurdles, etc., for crossing ditches, covering trous de loup, and other purposes; and, when necessary, ladders for escalade—move forward with the columns of attack; the latter must be so handled that, when the artillery fire is suspended, they can keep down the fire of the defence with rifle and light machine-gun fire.
Under cover of this fire the obstacles must be removed by the working parties, and the first assault made by the troops detailed for this purpose. With these troops should be a certain number of artillerists provided with lanyards, friction primers, etc., to serve any guns that may be captured, turning them against the defence.
A party of engineers provided with high explosives for blowing down gates, etc., should follow closely behind the advance in case of an escalade; they should also be provided with appliances for blowing up magazines, etc., when possible, in case of a repulse. The gates being captured and opened, the mass of the assaulting troops enter by them and complete the capture of the place.
In case of repulse the retreat of the advanced parties is covered, when possible, by the infantry fire of the reserves, and that of the latter by the artillery, as in the advance.