Jason appeared in the Register of Shipping (RS) for 1804 with Otway, master, W. Row, owner, and voyage Newcastle to Liverpool.

After the Treaty of Amiens, Britain had disarmed while France rearmed, so on the resumption of war the Admiralty found itself short of vessels for convoy escort.

Jason came into service with her original masts and yards even though she was under-canvassed and therefore slow, and without a cargo in her hold tended to roll; she became HMS Heron.

On the other hand, a fleet of 28 merchantmen and two transports had gathered in Carlisle Bay, awaiting a warship to escort them to Halifax or Britain.

Edgecombe decided to escort the convoy, risking court martial for leaving his duty station without orders.

Unfortunately, the French vessel was too low for Heron's guns to bear and rolled too much for her crew to secure grapnels.

Thereafter, Heron escorted convoys to Halifax, Newfoundland and Bermuda until December 1806 when Edgecombe, whose health had been impaired, left.

On 31 October 1814, while escorting a merchantman to Jamaica, Volcano nearly succeeded in capturing the 7-gun American privateer schooner Saucy Jack.

Under the rules of prize-money, Thames shared in the proceeds of the capture of the American vessels in the Battle of Lake Borgne on 14 December 1814.

[a] Volcano was sent up the Mississippi, with another bomb vessel, HMS Aetna, and Herald (18), Thistle (12), and Pigmy (10) to bombard Fort St Philip.

[11] After the British retired from New Orleans, Volcano sailed along the Gulf Coast and was present during the siege of Fort Bowyer in February 1815.