Enlisting in the US Army at Lansingburgh (since 1900 the northern business district of Troy), NY, 24 April 1861, he volunteered for service in the ironclad Carondelet 15 February 1862 and was appointed coxswain.
On 15 July, Carondelet under Comdr. Henry A. Walke, wooden gunboat Tyler and ram Queen of the West were on station in the Mississippi River near the mouth of the Yazoo River when the powerful Confederate ram Arkansas appeared, intent on joining the defense of Vicksburg, Mississippi downriver. In a running engagement, Arkansas passed the three Union ships, disabling Carondelet with a shot through her steering gear, then broke through Admiral David Farragut’s main blockading force and made Vicksburg. While Carondelet sustained 35 casualties during the battle, Morrison led showed exceptional bravery in leading the crew, for which he was later awarded the Medal of Honor.
Discharged 31 March 1863, Coxswain Morrison died at New York City 9 June 1897.