[629.] Except for urgent reasons, marches should not begin before an hour after daylight, but if the distance to be covered necessitates either breaking camp before daylight or making camp after dark, it is better to do the former.
Night marching should be avoided when possible.
[630.] A halt of 15 minutes should be made after the first half or three-quarters of an hour of marching; thereafter a halt of 10 minutes is made in each hour. The number and length of halts may be varied, according to the weather, the condition of the roads, and the equipment carried by the men. When the day's march is long a halt of an hour should be made at noon and the men allowed to eat.
[631.] The rate of march is regulated by the commander of the leading company of each regiment, or, if the battalions be separated by greater than normal distances, by the commander of the leading company of each battalion. He should maintain a uniform rate, uninfluenced by the movements of troops or mounted men in front of him.
The position of companies in the battalion and of battalions in the regiment is ordinarily changed daily so that each in turn leads.
[632.] The marching efficiency of an organization is judged by the amount of straggling and elongation and the condition of the men at the end of the march.
An officer of each company marches in its rear to prevent undue elongation and straggling.
When necessary for a man to fall out on account of sickness, he should be given a permit to do so. This is presented to the surgeon, who will admit him to the ambulance, have him wait for the trains, or follow and rejoin his company at the first halt.
[633.] Special attention should be paid to the rate of march. It is greater for trained than for untrained troops; for small commands than for large ones; for lightly burdened than for heavily burdened troops. It is greater during cool than during hot weather. With trained troops, in commands of a regiment or less, marching over average roads, the rate should be from 2¾ to 3 miles per hour. With larger commands carrying full equipment, the rate will be from 2 to 2½ miles per hour.
[634.] The marching capacity of trained infantry in small commands is from 20 to 25 miles per day. This distance will decrease as the size of the command increases. For a complete division the distance can seldom exceed 12½ miles per day unless the division camps in column.