Confederacy, C.S. Mill Prison, Charlestown S.C. "Aug 10" dateline on prisoner letter addressed to Brown's Corner, Maine, sent under separate cover and endorsed "via Flag of Truce", interesting relocation content…send me a box about the same as you sent me at Libby Prison…please direct you letters to Charleston, S.C. Mill Prison, Very Fine, a rare prisoner letter likely sent during the 1864 yellow fever outbreak in Charleston. Estimate  $300 - 400. $0 (Image)