He saw action as a midshipman at the battle of Dominica in 1782, was first lieutenant of the Sibylle during her capture of the Forte in 1799, and commanded the Unicorn at Monte Video in 1807, and at the Basque Roads in 1809.

[1] He entered the Royal Navy in 1781 on board the Repulse, with Captain Thomas Dumaresque, and in her was present in the battle of Dominica, on 12 April 1782.

[1] He was first lieutenant of the Sibylle when, on the night of 28 February–1 March 1799, she engaged the French frigate Forte, and succeeded to the command when Cooke was carried below mortally wounded.

[1] Hardyman was acquitted of all blame, but the master of the flagship, who was piloting her in, was sentenced to lose twelve months' seniority.

[1] In 1803 Hardyman commissioned the Unicorn frigate, which he commanded in 1805 on the West India station; in 1807 in the expedition against Monte Video under Sir Charles Stirling;[3] and in 1809 in the Bay of Biscay under Lord Gambier, and was present at the destruction of the French ships in Basque Roads on 11 April, when the Unicorn was one of the few ships actively engaged.