Oswald Garrison Villard, John Brown, 1800-1859: A Biography Fifty Years After (New York: Houghton Mifflin Company, 1910), 682-683.
Barclay Coppoc was born at Salem, Ohio, January 4, 1839, and had not attained his majority at the time of the raid. He escaped from Harper's Ferry, but only to meet a tragic fate in that he was killed by the fall of a train into the Platte River from a trestle forty feet high, the supports of which had been burned away by Confederates. Coppoc was then a first lieutenant in the Third Kansas Infantry, Colonel Montgomery's regiment, having received his commission July 24, 1861. Barclay Coppoc went straight to Iowa after his escape from Harper's Ferry, whither Virginia agents followed to attempt his arrest. He went back to Kansas in 1860, helped to run off some Missouri slaves, and nearly lost his life in a second undertaking of this kind. The accident which ended his life took place at night; he survived his injuries until the next day, September 3, 1861. He was buried at Leavenworth, Kansas. He was in Kansas for a time in the fall of 1856.