The collections consists of a letter from Union soldier Henry M. Warren, Private of the 18th Regiment, Massachusetts Infantry, to his brother Nathaniel in Massachusetts. Warren's letter, dated November 9, 1861 and written from Hall's Hill, Virginia, includes details about how the soldiers in the unit are kept busy in their down time (mostly drill and review), including a troop review that Warren says was attended by President Lincoln, who he refers to as "Old Abe."