tied by blue "Balto Paid" with matching "Baltimore Md. Sep 22" datestamp alongside, on 1863 cover addressed to "Mr. Elbert Corbin, General Hospital, Gettysburg, Pa", barely reduced at left, very fine, Corbin (Battery B, 1st New York Light Artillery) was left behind after the Battle of Gettysburg to tend to the wounded (including both Union and Confederate soldiers)