The disastrous 1779 Penobscot Expedition was conveniently forgotten by many, especially the general population and most certainly by Massachusetts officials. Over time, it became a localized memory; Mainers perhaps knew about the event but knowledge of any actual locations of wreckage or anything faded over time.

This all changed in the 1950s when the General Chamberlain Bridge was built, spanning the Penobscot River between Bangor and Brewer. Work on the structure paused when four Armstrong cannon were recovered during construction. Their recovery became big news when they were identified as Revolutionary War-era cannon from the ill-fated Penobscot Expedition.

The Penobscot Expedition by marine artist Dominic Serres (1722–1793) showing the bay viewed from the south. In the left background is Collier’s flagship Raisonable with white ensign and broad pendant firing into the American vessel Hunter. Public Domain

The cannon had been carried aboard the Continental Navy’s sloop Providence, one of the many ship casualties of that ill-fated campaign. One was preserved and mounted; today it overlooks the Penobscot River near Sea Dog Brewing Co.’s Bangor restaurant.

Soon, other wrecks were found along the river, including the Warren, flagship of expedition leader Commodore Dudley Saltonstall. It was not until the 1970s, when one of the best-known wrecks from the expedition was found.

It was the privateer Defence. During that dark day when the entire enterprise fell apart, the 16-gun colonial brig had tried to make a run around the approaching British relief force under Adm. Sir George Collier. As the rest of the rebel ships set off up Penobscot River, the 90-foot-long Defence tried its luck fleeing to the west side of Penobscot Bay. It did not work.

The backside of Brigadier or Sears Island (to the right) over toward Stockton Harbor (to the left) where Defense hoped to evade detection. Photo by Charles H. Lagerbom

The 170-ton brig had been built in Salem, Massachusetts; another source says Beverley. It was owned by Andrew Cabot and Moses Brown; another source says Morris Brown. Regardless, it was being set up for privateering in late 1778, just months before the expedition formed.

As a result, Defence was on its maiden voyage when it was lost. It carried a crew of 100, along with 16 6-pounder cannon, under command of Capt. John Edmonds.

Stockton Harbor today with Brigadier or Sears Island (to the left). Photo by Charles H. Lagerbom

Once the expedition fell apart, like the other American ships, Defence had to shift for itself. They slipped into a small inlet behind Brigadier Island, hopping to sneak away after darkness. Today, Brigadier Island is known as Sears Island. But the ship was spotted by a Capt. Collins of the pursuing HMS Camilla, who decided to sit and wait off the island for the brig to make its move.

Capt. Edmonds realized escape was impossible. They would have to destroy their own ship to keep it from being taken by the British. Edmonds ordered the crew into longboats along with some stores, while others prepared the ship’s powder magazine to detonate.

The magazine, located toward the stern next to the shot locker and bilge-pump, was below Edmonds’ quarters. It was also beneath the vessel’s waterline. When it ignited, the explosion blew a huge section off the stern and created a trough in the mud below the ship.

Defence’s masts disappeared in the blast and with no stern, the brig rapidly sank. Silt and mud soon covered the sunken deck. It is likely the British made an effort to salvage some of its 16 cannon, since later excavations recovered only two. After the shock of the disaster and with the continuation of the war, the vessel’s true location was soon forgotten.

Mill Cove, the far back side of Stockton Harbor, where Defense may have ended up trying to evade the pursuing British ships. Photo by Charles H. Lagerbom

At the Hutchinson Center in Belfast a few years back, I took an underwater archaeology class taught by Dr. Warren Reiss, who was then at the University of Maine’s Darling Center in Walpole. He had been part of the Defence investigation back in the 1970s, so I got to hear some of his stories about it.

It was a pretty big deal. Dr. George Bass, then president of the American Institute of Nautical Archaeology got involved. Bass, considered one of the founders of maritime archaeology, even dove on the wreck and declared it a historically important time capsule. The Defence excavation was AINA’s first project in the New World, previously having only worked on Mediterranean shipwrecks.

AINA archaeologist Dr. David Switzer worked with ocean engineer David Wyman of Maine Maritime Academy in Castine. MMA provided field support, faculty, equipment and facilities. Maine State Museum was then added, bringing in a museum conservator for recovered materials. This multi-group effort was called Project Heritage Restored.

In the summer of 1972, sonar imaging was used by personnel from MMA and Massachusetts Institute of Technology to pinpoint the wreck’s position. They found it sitting about 25 feet below the surface, encased in a solid mud shroud. It was a major find, important enough that in 1975 the wreck site was listed on the National Register of Historic Places.

Between 1976 and 1981, the site was thoroughly excavated. Dive conditions were tough. One person likened it to putting your head inside an inkwell; visibility was often less than 4 feet. Doing mooring work off Winterport, just a bit farther upriver, I’ve found the water turns chocolate brown and then quickly black 3 or so feet below the surface.

The archaeology crew lowered a 25-foot square plastic grid of 5-foot squares over the fore peak, the extreme forward part of the hold, in the angle formed by the ship’s bow. They used a 4-inch airlift to suck out mud and debris into a sieve, while workers on the barge above cleaned and cataloged the collected artifacts.

Shoes, some with buckles still attached and buttons made of wood, leather or metal showed up, as did pewter spoons. They even recovered a monogrammed wooden wash bucket. One exciting find was a metal button stamped “USA,” no doubt from the uniform of a Continental Marine.

The cookstove was located, its brick hearth and large copper cauldron still there. Bricks were individually marked for later reassembly. They even removed the remaining stump of the main mast, which apparently surprised everyone by floating to the surface.

Other remains included numerous clay tobacco pipe fragments and cobalt bottles for rum. The cramped crew quarters were recognized to have had “hot bunks” where half the crew slept in them while the other half were on duty. The term comes from the fact the bunks or hammocks had no time to cool off before the next body occupied it.

Two iron cannon and several cannonballs were also recovered. The armaments were sent to be preserved at the Naval Research and Development Center in Annapolis, Maryland.

One of the cannon was found to still be booby-trapped — Edmonds’ men had tried to make sure the cannon would be of no use to the British. When excavated, the charge was found to still be live and had to be moved to the Naval Ordnance Depot to be disarmed! Yikes!

As far as ship architecture went, researchers discovered Defence was longer and sleeker than what had been assumed for Revolutionary War-era American-built ships. In fact, it showed features more akin to the coming clipper ship-type of vessel design, with sharp and clean lines and higher prow.

Many Defence artifacts were put on display at the Maine State Museum and remains of the hulk where then reburied under a layer of mud. Since then, archaeologists and the state are hesitant about revealing the wreck’s actual location. This is understandable, as the hope is to avoid any unofficial scavenging or disturbing what remains at the historic site.

That is why you will only find vague references to Stockton Harbor or that the wreck is near Defence Point (formerly Squaw Point) and Defence Head, which were named in honor of the wreck.

Efforts to learn more about Defence have revealed insights into the everyday life of 18th century American sailors, Continental Marines and colonial New Englanders. It has produced one of the first sets of plans from an American-built Revolutionary War era vessel. And it all happened right here in our own backyard!

Charles Lagerbom teaches AP U.S. History at Belfast Area High School and lives in Northport. He is author of “Whaling in Maine” and “Maine to Cape Horn,” available through Historypress.com.