William P. Mason Co F 12th NH Vols
of Canterbury, N.H., enlisted in Company F of the New Hampshire Twelfth Regiment on August 15, 1862 and mustered in as a Private the following month. After seeing action at the battles of Fredericksburg and Chancellorsville, he was promoted to the rank of Corporal on May 1, 1865, seven weeks before being mustered out. He was born in Alton, N.H. in 1842 and died, aged only 25, in St. Charles, Minnesota in a drowning accident June 30, 1867.
Reference: University of New Hampshire Library Special Collections http://www.izaak.unh.edu/specoll/mancoll/civwar.htm