From 1819 until 1821 he served in the West Indies on the sloop-of-war USS Hornet in the suppression of the African slave trade.
He was detached as special messenger to bring home the ratified treaty with Naples, and from 1835 till 1837 served in the Mediterranean squadron.
Two decades of further duty afloat and ashore, including a long assignment with the Bureau of Ordnance and Hydrography, were recognized with Commander's rank in 1848.
[1] After 1855 Captain Harwood served in shore posts, among them a tour as Chief of the Bureau of Ordnance and Hydrography in 1858–1862.
Beginning in 1869, when he was promoted to rear admiral on the Retired List, he held legal positions, concluding with a year as the Navy's Judge Advocate in 1870–1871.