Military service
Dyer's military career began in October 1856 when he enlisted in the First Light Infantry, a prestigious unit of the Rhode Island Militia located in Providence. On April 8, 1858, at the age of eighteen, he was appointed by his father as a colonel and aide-de-camp on his father's military staff. He relinquished the position when his father left office in May 1859.
On the outbreak of the Civil War, Dyer enlisted as the 4th sergeant of the 1st Light Artillery Battery of Rhode Island on April 15, 1861. Sergeant Dyer was sent with the battery to Easton, Pennsylvania to train other volunteer artillery units. Dyer was discharged shortly after his arrival due to accidental injuries he suffered after an explosion of a limber chest, on April 21, 1861.
On September 28, 1861 he was commissioned lieutenant and commissary of the Providence Marine Corps of Artillery. He was promoted to captain on April 28, 1862 and to major on June 7, 1862. He also served as military aide-de-camp to Governor James Y. Smith, with the rank of colonel, from May 26, 1863 to May 29, 1866.
On June 7, 1869 he was elected lieutenant colonel commanding the Providence Marine Corps of Artillery, serving until April 24, 1871. He was re-elected as lieutenant colonel of the Providence Marine Corps of Artillery on April 29, 1872 and served until April 27, 1874. On May 10, 1875 he was commissioned as a lieutenant colonel and was placed in command of 1st Battalion of Light Artillery and served until May 13, 1878.
On February 7, 1882, Dyer was appointed as adjutant general of the Rhode Island Militia and was promoted to the rank of brigadier general. He held this position until October 31, 1895 when he retired at his own request. His 13 years in office was one of the longest tenures in that position.
