He fought in the War of American Independence, taking part in the French operations in the Indian Ocean under Suffren, and was one of the experts in the inquiry on the wreck of the frigate Méduse.
[2] On 12 January 1783, Herlye was given command of the recently captured Coventry.
[3] Between 1783 and 1784, he was demoted to Ensign, but on 31 July 1784, he was promoted back to Lieutenant, and awarded a 400-Livre pension.
[2] Herlye was promoted to Captain in 1814, working first as under-Director of the harbour.
[2] In March 1817, Herlye was secretary in the inquiry on the wreck of the frigate Méduse.