Blocksom was commissioned as a second lieutenant of cavalry on June 15, 1877. He later received a brevet to first lieutenant for gallantry at
Ash Creek, Arizona, on May 7, 1880. He served in campaigns against the Apaches in Arizona, which included patrolling the Arizona-New Mexico border, Blocksom also reported that no positive identifications of the raiders had been made and that tensions in the community were high. He commanded a squadron of the Sixth Cavalry during the China Relief Expedition. He retired on November 7, 1918. ==Awards==