He served as Professor of Military Science and Tactics at Brooks Military Academy of Ohio from 1881 to 1883, being promoted to first lieutenant in February 1883. Rejoining the regiment at Fort Snelling, Minnesota in September 1883, he became the regimental adjutant in August 1886. The regiment moved to Fort Missoula, Montana in September 1889, and Andrews was promoted to captain in September 1892. He served on duty with the Ohio Army National Guard from 1896 to 1898.[1][2]
In February 1898 Andrews transferred to the Adjutant General's Department and was promoted to major, serving as adjutant general for the Department of the Missouri, and later for the Department of the East and in Cuba. He served in the Adjutant General's Office in Washington, D.C. from September 1900 to October 1902, and was promoted to lieutenant colonel in February 1901. He served as adjutant general for the Department of California from October 1902 to January 1904, receiving a promotion to colonel in August 1903. He then served as adjutant general for the Pacific Division from January 1904 to November 1905 when he became adjutant general for the Philippines Division.[2][3]
Andrews continued to serve in various departmental adjutant roles from 1908 to August 1912 when he was appointed as Adjutant General of the United States Army with the rank of brigadier general.
^ abCullum, George W. (1910). Biographical Register of the Officers and Graduates of the U. S. Military Academy, Volume V. Saginaw, Michigan: Seeman & Peters. pp. 247–248.
^Cullum, George W. (1920). Biographical Register of the Officers and Graduates of the U.S. Military Academy, Volume VI. Saginaw, Michigan: Seeman & Peters. p. 219.