NEW YORK, NY.- As the SS Arlington, a Canadian ship carrying wheat across Lake Superior, started to sink in stormy weather May 1, 1940, its crew clambered into a lifeboat and then gazed upon a strange sight.

There, across the stormy waters, was their captain, Frederick Burke, known as Tatey Bug, waving to them from the Arlington’s deck, moments before he went under with his ship.

The odd behavior of the captain, a solitary figure who was left alone after his men escaped, remains a mystery. And it is likely that an explanation, like the ship itself, will never surface, according to researchers at the Great Lakes Shipwreck Historical Society, which announced Monday that the Arlington had been found off the coast of the Upper Peninsula of Michigan.

“The question is whether he was saying, ‘Hey, hold the lifeboat’ or waving goodbye,” said Dan Fountain, a researcher who volunteers with the historical society and first detected the abnormality in the lake floor that led to the discovery of the Arlington last year.

Hundreds of ships have sunk in the Great Lakes, imperiled by stormy waters as they crossed with cargo. Many of the wrecks have been found over the years, slowly coming into view from the murky depths with the help of sonar or satellite technology.

As with the Arlington, the wrecks can be seen, but the details of the ships’ final moments are often never to be discovered.

Lake Superior, the world’s largest freshwater lake by area, has served as a major commercial shipping corridor for centuries. Hundreds of wrecks are estimated to be in the nearly 32,000-square-mile lake.

As lake floor silt is unsettled with currents and time, the wrecks make themselves known in stages. Disturbances in the lake floor show up in remote sensing data and then are confirmed with side-scan sonar, which sends and receives acoustic pulses that help map the lake floor and detect submerged objects. Then remote-operated vehicles pick up the details.

Artifacts, ship hulls or steering wheels drift into view. The ships are rarely brought to the surface, because it is too costly and against the law in Michigan. Surviving manifests and crew lists are combed for clues to shipboard life.

Some keep their secrets to themselves. The Edmund Fitzgerald disappeared in driving snow in Lake Superior in 1975, taking with it 29 men and becoming a cultural legend thanks to Gordon Lightfoot’s haunting folk ballad. The schooner Atlanta, lost in 1891 and found in Lake Superior in 2022, revived the tale of the six crew members who clung to their lifeboat, only two of whom survived after it capsized.

The Arlington has retained its most closely guarded secret, taking with it any explanation for the behavior of Burke in the ship’s final moments of distress as 10-foot waves washed over its listing deck.

“The stereotype is that the captain goes down with the ship,” Bruce Lynn, the executive director of the historical society, said in an interview Monday. “But there was plenty of time for that captain to get out of his pilothouse and be part of that crew that was going to be rescued.

“So I think it was the mystery of what the captain was doing that makes this unique,” he said.

Loaded with wheat, the Arlington set off from what is now Thunder Bay, Ontario, on April 30, 1940, for Owen Sound, Ontario, with a 16-member crew. The ship and a nearby freighter, the Collingwood, encountered dense fog. By nightfall the ships were battered by a storm, the Great Lakes Shipwreck Historical Society said in a statement.

Burke, who had made many journeys on the lake, had made decisions since the storm started that baffled his crew, the historical society and Fountain said, citing contemporaneous reports from the time of the ship’s sinking.

As the Arlington began to take on water, its first mate, Junis Macksey, gave orders to hug the northern shore, hoping for protection from the wind and waves. But Burke demanded that the ship stay its course across the open water.

On May 1, around 4:30 a.m., the Arlington’s chief engineer, Fred Gilbert, sounded the alarm as the ship started to sink. The crew began to abandon ship in the absence of an order from their captain, and made it to the Collingwood, the historical society said.

Lynn said the captain had spent a lot of time in the Arlington’s pilothouse as the ship was in distress, and there was confusion about why he was waving. Some crew members said they believed he was ill or had fallen and was unable to get on the lifeboat.

“The last man in the wheelhouse simply said he was not coming,” Lynn said. “There is speculation about this veteran of the lakes. Why was he acting the way he was acting? What was happening in those final moments?”

Fountain, the researcher, detected an abnormality on the lake floor, about 35 miles north of the Keweenaw Peninsula in Michigan, in 2019. Since it was confirmed to be the Arlington, partly sitting upright and largely intact, he has been trying to find descendants of the crew in Midland, Ontario.

“It solved a mystery, saying we now have an ‘X’ on the map instead of a blur in this area,” he said. “We are happy to have found it. But it is also sobering when you realize it is also Captain Burke’s grave.”

This article originally appeared in The New York Times.