At daylight on the morning of September 19 one division of cavalry, which had the advance, engaged the enemy near Opequon Creek, five miles from Winchester, and drove him from his position, which it held until relieved by the infantry. The battle during the morning was fought with great obstinacy, and, with the exception of occasional slight checks to some of our corps, success was always in our favor. About 3.30 p.m. a combined advance of infantry and cavalry was ordered, the cavalry operating on both flanks. This resulted in the complete triumph of our arms, and the enemy fled from the field routed and demoralized. That night we occupied Winchester. The field hospitals were established during the day on or near Opequon Creek, and their locations were well protected from the shot of the enemy by wooded hills. They were all in the immediate vicinity of good roads. The wounded, as a general thing, received good care, and had nourishing food promptly administered to them. During the latter part of the day, however, it was impossible to collect all the wounded, as the army pushed on so rapidly, thereby increasing the distance for the ambulances. Quite a large number, therefore, remained on the field that night, many being concealed in the thick woods where they had fallen. At 9 p.m. the same night the general commanding ordered me to have all the wounded taken to Winchester, and the field hospitals broken up as rapidly as possible. For this purpose a detail of medical officers to remain was made from each corps, a certain proportion of ambulances was ordered to be left, and the chief quartermaster placed at my disposal all the empty army wagons. Asst. Surg. H. A. Du Bois, U. S. Army, assistant medical director, was ordered to remain and take general direction of the removal of the wounded and of the establishment and organization of hospitals in Winchester. That night I informed you by telegraph of the result of the battle, gave the approximate number of wounded, and requested you to send forward to Winchester twenty medical officers, hospital supplies for 5,000 wounded, and an experienced surgeon to take charge of the hospital. Several weeks previously the chief quartermaster had, at my request, ordered the post quartermaster at Harper's Ferry to keep on hand 300 hospital tents for such an emergency. Doctor Du Bois reported to me on the 21st that he had seized a portion of the army train, unloaded it, and with the ambulances left him had transported all the wounded from the field to hospitals which he established at Winchester in the churches, public buildings, and such private dwellings as were suitable. These hospitals he organized by corps. Being almost destitute of food for the wounded, the commanding officer of Winchester took, at his request, 8,000 rations from an army train which was going to the front. This embarrassment arose from the fact that no subsistence train accompanied the army. Things were soon systematized, and over 4,000 wounded were safely transferred to the hospitals of their respective corps, competent surgeons placed in charge, and the most experienced and expert operators designated to perform the operations.
On the evening of the 22nd Surg. J. H. Brinton, U. S. Volunteers, arrived with five medical officers, and relieved Doctor Du Bois, who returned to headquarters on the following day. Four hundred hospital tents, ample supplies, and ten additional surgeons arrived on the 23rd. About 300 hospital tents were pitched on a well-selected site near the town, and a camp hospital organized under the designation of Sheridan Field Hospital. Surg. F. V. Hayden, U. S. Volunteers, was assigned to its charge.