STC355119 Allan Pinkerton at Antietam after the battle, 1862 (b/w photo) by Brady, Mathew (1823-96) & studio; Private Collection; (add.info.: Allan Pinkerton (1819-44) a Scottish detective and spy, founder of the Pinkerton National Detective Agency and head of the Union Intelligence Service 1861-62 (seated, right); Battle of Antietam, also known as the Battle of Sharpsburg, fought on September 17th 1862 near Sharpsburg, Maryland;); The Stapleton Collection; American, out of copyright.