Furious, McLoughlin sent the hapless Ryan and his crew back down the river to their ship to save what they could. In a letter to his superiors, he reported: “When Capt. Ryan arrived here he could not distinctly ascertain where he had left his vessel… it was only when I received Mr. Mansons [report] I actually learnt where she was and if Capt. Ryan had remained on board with his crew it is certain the vessel would have been saved as on the turn of the tide they had only to slip her cable and she would have drifted into smooth water.”

When Ryan and his crew arrived back at the wreck, they found Isabella on her side on a small island just inside the river’s mouth. She was full of water and, as the incoming tide washed away the sand that swirled around the hull, was slowly being swallowed up. The first task was to save the valuable cargo still inside the brig.

The next few days were spent stripping the wreck. The masts and rigging were chopped free and stacked on the island, and the crew began to unload the cargo from the dark, wet confines of the hold. Work stopped each day at high tide, when the heavy surf that broke over the capsized hulk made it dangerous to even approach the wreck. The hold flooded each day, making each day a repetition of pumping. After two weeks of back-breaking work, Isabella was at last emptied and the task of trying to save the dismasted hull began.

But the sand and the sea would not relinquish the wreck. A survey on May 24 found the brig settled into a deep hole, the hold full of water, beams cracked, decks and bulwarks washed away, and the hull beginning to crack in half. It was hopeless, and the surveyors wrote to McLoughlin that any attempts to save Isabella “would be an unnecessary sacrifice of labour… as we consider her a total wreck.” With that, the ship was abandoned to the water and the sands of the Columbia bar.

Although the sands of the bar had swallowed Isabella, occasionally they washed away to expose some broken timbers. Charts from 1880 to 1921 mark a wreck at the site where, in September 1986, Daryl Hughes, a commercial fisherman, snagged his nets. Other fishermen had snagged nets there, but Hughes was the first to send down a diver, who reported that Hughes’s net was wrapped around the hull of a wooden ship. Hughes, who knew the river’s history, thought that he might have found Isabella and reported the discovery to the Columbia River Maritime Museum, just across the river from the wreck site.

The museum’s curator, Larry Gilmore, enlisted the support of a number of people, notably Mike Montieth, the Coast Guard commander of the “Cape D” station. An avid wreck diver himself, Montieth led a group of volunteers on a series of explorations of the wreck. In the murky darkness, Montieth began to sketch out the sloping sides of a wooden ship with a series of what looked like gun ports, a discovery that puzzled the investigators. Perhaps the hulk emerging from the sand wasn’t Isabella after all, but USS Peacock or USS Shark, two warships lost on the deadly Columbia River bar in 1841 and 1846. A sand-encrusted cutlass from Shark and a rock with a message carved into it by the survivors of that wreck are among the prize exhibits at the Columbia River Maritime Museum, relics of one of the hundreds of ships lost at this graveyard of the Pacific.

To help resolve the questions, our National Park Service team was called in. The team leader, Daniel J. “Dan” Lenihan, who is an intensely focused, hardworking archeologist with a quiet demeanor, created the U.S. government’s first field team of underwater archeologists. The work of Dan and his team has also revolutionized underwater archeology in the United States, both in the way that work is done in the water and how archeologists think about shipwreck sites.

The team that assembles at Astoria in August 1987 includes Dan Lenihan, myself and another adjunct member of his team, Larry Nordby, who looks like a Viking and whose skill in the science of archeology is enhanced by the ability to measure and draw the remains of ships on the bottom in the worst possible conditions. We three are joined by volunteers — Mike Montieth, local shipwreck historian and wreck diver James Seeley White, and other local divers who have already been exploring the wreck of Isabella.

As we gear up on the boats that are tied off the line that Mike has rigged to the wreck, he and Dan brief us. The wreck lies in only 48 feet of water on a hard sand bottom. That’s the easy part. The tough part is that the current rips through at such a fast pace that a diver can’t hold on when the tide ebbs and flows, so we can only go in the water at slack tide, when the current dies down to a dull roar. It’s also dark down there. Mud in the water near the surface blocks the light, so we have to feel our way over the broken wooden hulk, guided by a flashlight that illuminates just a few yards ahead. Then there are the fishing nets and crab pots caught on the ship’s protruding timbers, along with fishing line drifting in the current, to snag dive gear and unwary divers.

This is not going to be easy. In fact, I’m scared, but not enough to stay out of the water. We all jump in and make our way to the buoy that marks the wreck. The current tugs and pulls at us. Dan looks carefully at each one of us, checking to see if we’re ready. With a series of nods, we vent the air from our buoyancy compensating vests and start down the line, into the dark water.

The green water becomes gray and then black. Then, suddenly, I land on a thick wooden beam, encrusted with barnacles and wrapped with the buoy line. I’m on the wreck. Mike and the other divers have done an excellent job of sketching the basic outline of the wreck — the curving side of the hull, with ports open in what may be two rows. I turn and put my face close to the hull to examine it better, then switch on my light and follow Larry and Dan as we make a quick inspection of the hull. It is clearly half of a ship, with broken beams and timbers indicating where the decks were. From the weather deck to the bottom of the hull, this half is nearly complete, though we don’t yet know which side of the ship it is. Later dives will confirm that it is the starboard, or right-hand side, of the wreck.

Dan has asked me to take a careful look at the ports to see if they are for guns. Six of them, in a row, line the hull below the level of the deck. They are small square ports — they seem too small to be for guns, I think — and I run my gloved hand along the top of one to check for hardware or the hole for a lanyard to pull open a gun port. The wood is solid, and there is no evidence of hinges or other hardware. They look to be cargo ports — square holes cut to load bulk cargo like coal or grain, then plugged with wood and caulked for the voyage. To make sure, I inspect each one. My reward for this meticulous work is a sudden encounter with the rotting head of a salmon, stuck in a wad of net inside one of the ports, its empty eye sockets staring at me as I stick my head into the port. It gives me a start, and I hit my head on the top of the narrow aperture and curse.

Dropping further down, I look for the second row of ports. I find only one opening, and after examining it closely, I decide that this is not a port. It is a roughly square hole that has been cut into the side of the ship. The rounded corners indicate that an auger was used to drill through the thick planks. The preservation of the wood, buried in sand and kept intact by the brackish water of the river where wood-eating organisms cannot survive, is remarkable; taking off my glove, I can feel the edges where a saw has bitten into the wood to cut out the hole. Some of the edges of the planks are splintered, as if an axe was used to help open up the hole. I smile, for this, I am sure, proves the wreck is Isabella.