Owing to the difficulty of recognition, a distinguishing mark will usually be worn by the troops engaged, a watchword will usually be adopted and made known to all ranks, and the commander and staff should wear easily distinguishable badges. If hostile patrols are encountered it is essential that they should be silenced, and any one encountered who is deficient of the badge and ignorant of the watchword should be similarly treated. The risk of an assault being held up by unforeseen obstacles must also be provided against, and Engineers or Pioneer Infantry should be present for removing such obstacles. If fire is opened by the enemy it is clear that all hope of surprise has vanished, and the troops must then press on at all costs; for if they advance as rapidly as possible they have a reasonable prospect of achieving their object, whereas a halt will increase the enemy's power of resistance, and withdrawal will almost certainly end in disaster. In order that secrecy may be observed, details of the assault will usually be withheld from all except superior commanders from whom action is required, until the Position of Assembly is reached; but before the troops leave that position all ranks must be made to understand the objective in general, the particular task of the unit, and the formation to be adopted at the Position of Deployment. In addition to this information, and to a knowledge of the general tactical principles involved, {154} there are certain axioms which must become "rules of thumb" with all ranks:-- Fire must not be opened without orders. Magazines must be charged but no cartridge placed in the chamber. Until daylight the bayonet only to be used. Absolute silence to be maintained until the signal for the assault is given. No smoking; no lights. If obstacles are encountered each man will lie down in his place until they are removed. If hostile fire is opened, all ranks must press on at once with the utmost spirit and determination and overpower the enemy with the bayonet. {155} FIGHTING IN CLOSE COUNTRY Close country has a marked influence on Tactics owing to the restrictions it imposes on view and on movement. Forest, jungle, and bush, mountains and ravines, rivers and streams are natural obstacles, while cultivation adds woods and plantations, fences and hedges, high growing crops, farm houses, villages and towns, with sunken roads below the surface of the adjoining land, and civilisation brings in its train a network of railways and canals with embankments and bridges, and the natural difficulties of close country are thereby increased. The obstruction to movement is more or less constant, except in "continental" climates, where frost and snow render movement possible in winter over the deepest rivers or marshes, and over roads and tracks which are scarcely practicable in the summer season. The obstruction to view is greater when trees and hedges are in leaf than when the leaves have fallen.