I remained on duty at Carver hospital, Washington, D. C, until the night of September 17, 1862, when, with some sixty or seventy others, I was ordered to report to Medical Director Letterman, Army of the Potomac, for temporary duty in the field. The party took a special train, and after traveling all night arrived at the Monocacy on the following morning. The bridge across this stream having been destroyed by the rebels in their retreat, the greater portion of our party were detained nearly all day, awaiting a conveyance to Rohrersville, the point of our destination, some twenty miles farther on. Assistant Surgeons Russel and Phillips, U. S. A., together with myself, separated from the main party early in the morning and made our way toward Rohrersville. We were, however, detained in Frederick City by order cf the Medical Director, and immediately set to work in the care of the wounded, who were by this time arriving by the thousand. The greater number of medical officers having been sent on toward the field, the work for those left in Frederick was almost incessant for a few days. I was temporarily in charge of the United States Hotel hospital, afterward part of Hospital No. 2, and continued in charge six or eight days, when I was relieved by Assistant Surgeon J. B. Brinton, U. S. A. I continued on duty in Hospital No. 2, until ordered to report to Assistant Surgeon General R. C. Wood, St. Louis, Missouri, which order I received on the 9th day of January, 1863 ...
After the battle of Antietam, most of the wounded were hurried on to Frederick, and from thence, those but slightly wounded, after being allowed a night's rest, were transferred to Washington and Baltimore. The hospitals in Frederick were densely crowded after the battle, and every available building used for hospital purposes. Some of these buildings were but poorly ventilated and ill adapted for this purpose; they were given up as speedily as possible. For the first five or six days, owing to crowding, it was almost impossible to keep the sick and wounded supplied with food and other necessities ...
The greatest inconvenience to which the wounded were exposed was in consequence of our not having an adequate number of beds to accommodate the thousands who were pouring in; and those but slightly wounded had to lie on the floor or ground, as they preferred, until the day after their arrival, when they would be transferred to Washington or Baltimore. I have counted as high as twelve hundred thus transferred in one train of cars. This crowding only continued for a few days, after which we had ample supplies and accommodations for those left. Thousands of those wounded in the upper extremities at the battle of Antietam walked in to Frederick City, some eighteen or twenty miles, all the ambulances being constantly busy in the removal of the more severely wounded.
Source: Extracts from a Narrative of his Services, MSHWR 1
1 Barnes, Joseph K., and US Army, Office of the Surgeon General, The Medical and Surgical History of the War of the Rebellion, 6 books, Washington DC: US Government Printing Office, 1870-1883, Part. 1, Vol. 1, Appendix, pg. 107 [AotW citation 19743]