He was discharged in March 1866 near Brownsville, Texas, and ten months later, joined the 40th Infantry under the name Thomas Bowen. The 40th Infantry consolidated into the 25th Infantry, in which he served until 1875. In 1875, he joined the 9th Cavalry. Not even Emanuel Stance had as varied a military background as Boyne among the 9th Cavalry prior to the cavalry's pursuit of Chief Victorio in 1879.[1]
In 1879, Boyne was serving as a Sergeant in Company C of the 9th Cavalry in New Mexico. His troop was in pursuit of Chief Victorio just prior to the Victorio's War.[1] He was cited for "[b]ravery in action" at the Mimbres Mountains on May 29, 1879, and at the Cuchillo Negro River near Ojo Caliente on September 27, 1879. For those actions, Sergeant Boyne was awarded the Medal of Honor on January 6, 1882.
Boyne had participated in eight of his regiment's fourteen engagements with Apaches when he initiated his request for a medal in 1880. His original request was for a Certificate of Merit, the award of which came with an increase in pay. Congress was only authorized to award one such award (either the Certificate or the Medal of Honor) and a legislative protocol reserved Certificates to private soldiers and Medals of Honor to officers.[1]
Rank and organization: Sergeant, Company C, 9th U.S. Cavalry. Place and date: At Mimbres Mountains, N. Mex., May 29, 1879; at Cuchillo Negro River near Ojo Caliente, N. Mex., September 27, 1879. Entered service at:------. Birth: Prince George's County, Md. Date of issue: January 6, 1882.