If your march should be through a country full of defiles, some cavalry and other light troops must march at the head of the columns, followed by a detachment of grenadiers and a brigade of artillery; cannon being absolutely necessary to obstruct the enemy’s forming into order of battle.
When you decamp in the face of the enemy, you must give most attention to your rear-guard. On such occasions, all the baggage, ammunition, provisions, and artillery, march before the troops; your best light troops, best cavalry, some good brigades of infantry, together with some brigades of artillery, form the rear-guard. Cannon is of infinite use for a rear-guard, when you are obliged to pass a defile, or a river; and should be placed at the entry of such defile, on an eminence, if there be one, or on any other place, from whence they can discover the ground through which the enemy must march to attack the rear-guard.
A detachment of pioneers, with tools, must always march at the head of the artillery, and of each column of equipage or baggage.
If the enemy be encamped on the right flanks of the march, the artillery, &c. should march to the left of the troops, and vice versa. Should the enemy appear in motion, the troops front that way, by wheeling to the right or left by divisions; and the artillery, which marches in a line with the columns, passes through their intervals, and forms at the head of the front line, which is formed of the column that flanked nearest the enemy, taking care at the same time that the baggage be well covered during the action.
Though we have said armies generally march in 3 columns, yet where the country will allow it, it is better to march in a greater number; and let that number be what it will, the artillery must form the centre columns. See American Mil. Lib. on the march of troops.
Line of march of the Artillery for a large army, as established before the French revolution:
1. A guard of the army; the strength of which depends on the commander in chief.
2. The companies of miners (excepting a detachment from each, dispersed in various places, to mend the roads) with tumbrels of tools, drawn by 2 horses, assisted by pioneers.
3. The brigades of artillery’s front-guard, with four light 6 pounders loaded, and matches burning.
4. The trumpeters on horse-back.