In August, "Endymion" took part in an expedition up the Penobscot River in Maine. The first ships to go were , , "Endymion", , , as well as some transports. , , , and joined on the 31st. On the evening of 31 August, "Sylph", "Peruvian", and the transport "Harmony", accompanied by a boat from "Dragon", embarked marines, foot soldiers and a detachment from the Royal Artillery, to move up the Penobscot under the command of Captain Robert Barrie of "Dragon". The objective was the American frigate , of twenty-six 18-pounder guns, which had taken refuge some 27 miles up stream at Hampden, Maine. Here "Adams" had landed her guns and fortified a position on the bank with fifteen 18-pounders commanding the river. Moving up the river took two days, but eventually, after the Battle of Hampden, the British were able to capture the American defenders at Bangor, though not until after the Americans had burnt the "Adams". The British also captured 11 other ships and destroyed six. The British lost only one man killed, a sailor from "Dragon", and had several soldiers wounded.