IV. _Connection_.--Every commander must have and must maintain a fixed place in the column, and an orderly officer must be detached from each unit to headquarters, so that instructions may be conveyed to such commanders at all times. Units must be closed up, and the usual distances lessened or dispensed with, and connection must be maintained between units and their sub-divisions. The pace should be uniform, but not more than 2 miles an hour can be expected on a dark night, including halts. The time and periods of halts should be arranged before starting, and units must regain any distance lost before halting. After crossing or clearing an obstacle the column should advance its own length and then be halted until reported to be closed up again, and staff officers should be detailed to superintend these matters. In addition to these general principles there are certain axioms, which must become "rules of thumb" with all concerned:-- An officer must march in rear of each unit. All ranks must be informed what to do in case of alarm or attack. Fire will not be opened without orders. Magazines will be charged, but no cartridge placed in the chamber. There must be absolute silence, no smoking, no lights. {147} When halted, men may lie down in their places, but must not quit the ranks. NIGHT ADVANCES.--Night advances are the movement of deployed troops to gain ground towards the hostile position with a view to delivering an assault at dawn. They may take place as a preliminary to an engagement, or to continue one already begun with increased prospects of success. In the first case they are usually the sequel to a Night March, and in either case they are generally followed by an attack at dawn. Surprise is the main object, even when they are undertaken for the purpose of gaining ground difficult to cross in daylight, from which to renew an engagement, as frequently happens during a campaign in a War of Manoeuvre, while such advances are common features of Position Warfare. In any case the ground won must be consolidated immediately, as a counter-attack at or before dawn may always be expected, and if the ground offers difficulties for entrenching, the necessary materials must be carried by the troops. Successive advances of this nature may enable the troops to reach a jumping-off place for the final assault, and such advances may be made on successive nights, the ground won being defended meanwhile against counter-attacks. Unless troops are already deployed for the advance, a Position of Assembly will need to be selected, with a further Position of Deployment; but these positions sometimes coincide. The deployment will be, as a rule, into shallow columns on a narrow frontage at deploying intervals, in order that the final deployment of the leading columns into the Forward Troops of the Attack may take place without delay when the moment for the assault arrives. On reaching the