The Department Commander desires that on your way up the Rosebud you should thoroughly examine the upper part of Tullock’s Creek, and that you should endeavor to send a scout through to Colonel Gibbon’s column, with information of the result of your examination. The lower part of this Creek will be examined by a detachment from Colonel Gibbon’s command. The supply steamer will be pushed up the Big Horn as far as the forks if the river is found to be navigable for that distance, and the Department Commander, who will accompany the command of Colonel Gibbon, desires you to report to him there not later than the expiration of the time for which your troops are rationed, unless in the meantime you receive further orders. Very respectfully your obedient servant, E. W. SMITH, Captain 18th Infantry, Acting Assistant Adjutant General. Custer was directed to march southward until he struck the trail Reno had discovered. If, as Terry supposed, it led across the Rosebud, he was not to follow it westward to the Little Big Horn, or until he met the Indians, but he was to turn to the southward until he struck the head-waters of the Tongue River. If he found no Indians there, he was to swing northward down the valley of the Little Big Horn, toward the spot where Terry supposed the Indians to be, and where, in reality, they were. Meanwhile Gibbon was to come up the Little Big Horn from the north toward the same spot. In the general plan of the campaign, Crook and his force were supposed to prevent the Indians from moving south—which they did, by the way. Custer was to keep them from going east, and, as he advanced, was “to feel to his left” to preclude all possibility of their slipping between him and Crook, while Gibbon was to keep them from going off to the north. The Indians would have no direction open to them for flight except westward, and in that case the troops hoped to overtake them in a difficult country, inclosed by mountains and rivers.