Rank and organization: Coxswain, U.S. Navy. Born: 1839, Boston, Mass.
Accredited to. Massachusetts. G.O. No.: 45, 31 December 1864.
Served as coxswain on board the U.S. Sloop John Adams, Sullvan's Island
Channel, 28 November 1864. Taking part in the boarding of the blockade
runner Beatrice while under heavy enemy fire from Fort Moultrie, O'Brien,
who was in charge of one of the boarding launches, carried out his duties
with prompt and energetic conduct. This action resulted in the firing of
the Beatrice and the capture of a quantity of supplies from her.
This data was extracted from the Committee on Veterans' Affairs, U.S. Senate, Medal of Honor Recipients: 1863-1973 (Washington, D.C.: Government Printing Office, 1973)