MARBLEHEAD, Ohio - Lake Erie has no sea monsters, but it may house a Lake Serpent.

The Lake Serpent, that is. After weeks of underwater excavation, a team of researchers and volunteers is inching closer to ruling on whether a wreck recently found near Kelley's Island is in fact the Lake Serpent, a ship known to have sunk in 1829.

If it is the Serpent, as suspected, the site would be the oldest known shipwreck in Lake Erie, a likely candidate for the National Register of Historic Places, and another significant feather in the cap of diver Tom Kowalczk and the Cleveland Underwater Explorers, the nonprofit group that discovered the wreck in 2015, during a scan of the area.

The work, funded by charitable donations and other gifts, has been slow and painstaking. Lake Erie is notoriously volatile, and to explore or work on the site, divers must have near-perfect conditions. On the research trip I joined last month, for instance, a second dive was called off after a barely perceptible uptick in wind speed.

Conditions underwater are even more unpredictable, and never good. The western basin, where the wreck is located, is the shallowest and murkiest area of Lake Erie, prone to algal blooms and stirred-up silt. Visibilty the day I dove was less than five feet, ruling out any hope of viewing or photographing the ship in its entirety.

Indeed, I could only feel, not see, the focus of the investigation: the figurehead at the ship's bow. If it's found to be a snake, it's safe to assume the ship is the Lake Serpent. Even there, though, lead researcher Carrie Sowden, archeological director at the National Museum of the Great Lakes in Toledo, had to physically place my hands on the area in question. It would have taken me ages to find it on my own.

I couldn't rule on its identity, either. To my hands, the wooden carving felt almost completely worn down, no surprise after sitting in just 45 feet of relatively warm water for nearly two centuries. Had the ship wrecked in the colder, clearer, and deeper waters of Lake Huron or Superior, the story might be different.

Little is known about the Lake Serpent. All Sowden and crew have to go on are two documents: an article in the Cleveland Weekly Herald reporting the loss of the ship and its load of stone, and the recovery of the bodies of Captain Ezera Wright and his brother, Robert; and a note in the Detroit Gazette detailing "a supposed breach of the revenue laws of Canada."

The whereabouts of two other passengers thought to have been on board is unknown. If they went down with the ship, their remains are no longer there.

My trip to the would-be Lake Serpent easily qualifies as the most interesting of my still-young diving career. I've been around and even inside wrecks much larger, more visible, and in better shape, but never have I witnessed or taken part in the process of researching and excavating a new site.

Reaching the wreck entailed a boat ride of about 45 minutes from Marblehead, near Sandusky. Once in the area, the team then had to find and attach their boat to a small, inconspicuous buoy two or three feet underwater. The site's location is being kept secret to ward off armchair archeologists, who might damage or steal from the wreck.

Sowden and I then took the plunge and followed a line through pea-green water down to the wreck. In addition to all the requisite diving gear, I carried an underwater video-camera and a small light of marginal utility. Much as bright lights hamper one's vision in a snowstorm, so does light fail to significantly improve the situation in murky water.

Once on the site, I spent most of the time observing Sowden in action. I hovered behind her and watched with fascination as she probed port-holes deeply crusted with zebra mussels, took measurements, and jotted notes on an underwater sketch-pad.

She also took me on a brief tour. With her as my guide, I swam around the front half of the 47-foot ship, the part not buried in silt, and all along its lengthy wooden bowsprit. Even if it's not the Lake Serpent, the wreck clearly pre-dates the Civil War. Sowden estimates the ship to be at least 170 years old.

I also leant a small hand in the excavation process. While Sowden did her work, another diver, David VanZandt, director of Cleveland Underwater Explorers, ran a long system of cables and hoses from a generator on the back of Kowalczk's boat and began sucking up and tossing away silt around the wreck. I helped get him started by unkinking a hose and holding the vacuum in position.

All told, I spent about 45 minutes on the site, and despite the poor visibility, I would have been happy to spend many, many more. I could have watched Sowden and VanZandt work all day, and I don't think there's any limit to the amount of time I would have been content in the immediate presence of a genuine historical artifact.

It may be some time until there's a verdict. Since my trip in late July, the team has made only one other dive at the site, and now can expect to make no more than two or three more before summer's end. After that, the window of opportunity closes, not to re-open until next year.

Fortunately, there's no rush. After 189 years at the bottom of the most tumultuous of the Great Lakes, the Serpent, or whatever it is, isn't going anywhere. Neither, too, are Sowden, Kowalczk, or VanZandt. Stewards of history, they won't stop until they have an answer.