[Indorsement.]

Colonel J. R. Hawley is charged with the execution of his order as far as it concerns his own command.

By order of Brigadier General A. H. Terry:

ADRIAN TERRY,

Assistant Adjutant-General.

GENERAL ORDERS, HEADQUARTERS TENTH ARMY CORPS,

Numbers 19. In the Field, near Hatcher's, Va., July 27, 1864.

The system of picketing for this corps will be that of Butterfield, with the following modifications:

The picket guard is divided into four reliefs. On marching on, the first relief goes onto the outposts, consisting of the groups of three and the outer sentinels; the second to the supports; the third and fourth to the guard grand. At the end of six hours the second relief moves from the support to the outposts, the first relief going to the supports. at the end of twelve hours the third and fourth reliefs go forward from the grand guard, relieving successively the outposts and supports, who return to the grand guard, the outposts first falling back on the supports. Each relief has thus twelve consecutive hours on grand guard. The outer sentinels are to be relieved every two hours and the groups every six hours. In extremely inclement weather, division commanders may authorize sentinels and groups to be relieved more frequently. twelve and three-quarters men for each sentinel's post gives the proper detail, with extra men for fatigue purposes, supernumeraries, &c. As a general rule, there should be in each relief one corporal for every three sentinels' posts, one sergeant for every six posts, one subaltern for every ten posts, and a captain or field officer commanding. For example, 20 posts give, say, 255 privates, 28 corporals, 12 sergeants, 8 lieutenants, and 4 captains. Commanders of divisions are responsible for the manner in which picket duty is performed on their division picket-line, and that the prescribed system of picketing, and the regulations on the subject are followed. The pickets of each division will be regularly mounted as a grand guard under the direction of the division commander. In permanent camps the guard may be continued on duty for three days. The picket-line of the corps, when once permanently established, will not be changed or modified unless such change shall be shall be sanctioned at these headquarters, or by orders from the corps officer of the day to the division officer of the day. On the march the pickets will be thrown out immediately on arriving in camp by the commander of each division (about one-tenth of their force), making their camps secure and their lines connected from right to left. The corps officer of the day will also see that this connection is duly made, and that all the are securely guarded.

No officer or soldier on picket will be allowed to return to camp during his tour, or to leave his post, unless so ordered by his commander then on duty, or from sickness. S medical officer will accompany each division picket. The pickets will not be permitted to converse with citizens, save duty, or with the pickets of the enemy. Small fires may be permitted by division commanders at the groups, never at the sentinel's post. When fires are permitted they must be made so as to be concealed from the observation of the enemy. The guard at the reserve and supports will habitually turn out at the approach of officers entitled to that honor. Sentinels will stand at attention, at ordered arms, when officers on duty pass their posts. The picket reserve and