Public domain
Petersburg, Virginia. Officers of 1st Massachusetts Cavalry at Army of the Potomac headquarters: unknown, Capt. Edward A. Flint, Capt. Charles Francis Adams, Jr., Lt. George H. Teague
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit linePetersburg, Virginia. Officers of 1st Massachusetts Cavalry at Army of the Potomac headquarters: unknown, Capt. Edward A. Flint, Capt. Charles Francis Adams, Jr., Lt. George H. Teague. 1864. Civil War Glass Negatives, Library of Congress. Public domain.