The American Revolutionary War

The Battle at Fort Mifflin

1. Background. As winter approached in 1777 the Colonial Revolutionists faced some very grim prospects:

a. The British had landed in Maryland and were marching northward towards Pennsylvania. On September 26, under the command of General William Howe, they captured the City of Philadelphia. Obtaining supplies from a fleet of 200 British ships waiting to sail up the Delaware before the river froze was critical to a British victory. Fort Mifflin, Fort Mercer, and the chevaux-de-frise (barges with small cannon strapped in position) were all that stood between Howe and the British fleet.

b. Further up the river at Trenton, General George Washington’s Continental Army was in full retreat, with the British following in close pursuit, from a stunning defeat at Brandywine. Their objective now was to cross the Delaware at Trenton and retreat to a relatively secure winter camp at Valley Forge. The British commanders dispatched HMS Augusta, a fast attack frigate, to sail up river to cut off Washington’s flee to safety.

2. HMS Augusta. When the Augusta was launched, she weighed 1,380 tons, but when fully loaded with 64 cannons, she weighed 1,450 tons. The British Navy considered her to be one of their finest ships, indeed. She was apart of Richard Howe’s fleet. Admiral Howe was the brother of Sir William Howe.

3. The River Battle. The Delaware River remained an obstacle that the British needed to control. They needed fresh supplies before winter which necessitated getting their ships up the river to Philadelphia. Benjamin Franklin had a unique plan, put chevaux-de-frise in the main shipping channel, between Billings Island and Billingsport, another group at League Island, and finally, a group by Fort Mifflin. This would have been an excellent plan but spies warned the British of the dangers. On OctOberg 21, 1777, five British ships, under the command of Captain Hammond, sailed up the river, attacking Fort Mercer on 22 October. The Hessian forces there led by Count Emil Kurt Von Domop, fought gallantly; several officers, including the Count, died. The Americans held tight to the fort.

The Augusta had advanced the British garrison further up river and ran aground near the mouth of Woodbury Creek. It was blamed on the “wind” which was Northerly and cold. The next day HMS Augusta continued up river.

4. Fort Mifflin. The main garrison at Fort Mifflin had been dispatched to Philadelphia in order to bolster Colonial forces there. Left behind to maintain the Fort were William Ritter and John Clawges an expert cannoneer. Both men were members of the Philadelphia Militia, 5th Company. That the Fort had been abandoned was common local knowledge which had been passed on to the British forces. As the British ships approached the Fort they were under constant observation by the two Militiamen left there. The lead ship HMS Augusta, encountering small arm fire from the chevaux-de-frise moved within close range for the Fort’s cannons, Captain Hammond apparently believing that the Fort had been deserted. The two Militiamen, with loaded cannons, lofted a high-angle shot that momentarily tangled in Augusta’s rigging and then abruptly fell onto the vessel’s wooden main deck, exploding on impact. A large fire erupted quickly burning through the damaged deck into the ship’s main ammunition magazine. The resulting explosion proved fatal to HMS Augusta which quickly burned and sanK.

According to Colonel Bradford’s report to General Washington the Augusta took part in an engagement with floating batteries. Then, after a very surprising and unexpected salvo from the Fort a fire aboard the Augusta spread and she went up in flames. After the Augusta sank the remaining four British ships fled down river.

Watson’ Anal of Philadelphia,d PA Scarborough Parker

Continental Transcripts - Council of Safety pg 723

6S. Pa. Archives, Vol 1, pg 282, 778