NEWBURYPORT — The shattered, nearly empty hull of the 36-foot Uniflite cabin cruiser that sank on June 24 during a thick fog at the mouth of the treacherous Merrimack River was towed into Newburyport's Cashman Park yesterday morning.

To experienced marine salvage expert Mike Goodridge, the remains of the boat — which have a large gash in the starboard, or right, side of the hull — told the sad tale of what most likely happened on the tragic night at sea. Unfortunately, the jagged, wrecked hull gave up no secrets about where the body of lost boater Seth Coellner might be.

Found and retrieved by Goodridge, of Tow Boat US, and diver Jim Whipple, there was no trace of Coellner's body under the capsized boat when it was turned over from its resting place, just northeast of the Merrimack River's north jetty.

"Out there, the currents run north, south, east and west," Whipple said. "If his body wasn't trapped under the boat when we turned it over, there's no telling where he might be."

Coellner, a 36-year-old husband and father from Kensington, N.H., is believed to have been driving the boat during harsh weather and sea conditions when the boat went down. A former Coast Guardsman and certified boat captain. Coellner is credited by Newburyport police with making the 911 call that gave the Coast Guard the ability to locate and rescue the other three passengers on the boat: Mark Baillargeon, 50, of 11 Chapel St., Newmarket, N.H.; Jacob Clark, 30, of 7 Landing Road, Hampton, N.H.; and Russell Hilliard, 50, of 212 Drinkwater Road, Hampton Falls, N.H. The four men had set off from Hampton Harbor on a cruise to Newburyport.

Goodridge said the retrieval of the boat was uneventful. Although seas were at high tide, it was the first time since they located the hull that his crew could safely dive, secure flotation devices and bring up the boat.

"It didn't take long to secure it, only about half an hour to 45 minutes," he said. "It was turned upside down, resting in pretty shallow water. With the swells and high tide, it was only in about 16 feet of water."

Once Goodridge saw the boat, its damage told the story. The long gash in the starboard hull starts about 6 feet from the bow of the boat and grows larger as it continues toward the back of the boat. Then it stops abruptly at what would have been the wall of the boat's bulkhead, although all remains of the bulkhead and foredeck are gone, as is most of the port, or left, side of the boat.

"The impact starts at the tip of the gash where the boat must have hit a V-shaped piece of granite," Goodridge said. "Then it just kept on ripping the hull until (the rock) hit the first bulkhead, where it must have stopped. That abrupt stop is what must have thrown the men in the water. Without a doubt, the boat hit a rock at the north jetty as it was entering the mouth of the river."

The exterior of the boat bears the evidence of what happened that night, both Goodridge and Whipple said. The bow of the boat shows a scar on its fiberglass tip, sustained with the first glancing impact of a rock. Scrapes along the next 6 feet of the starboard bow indicate the direction the boat was traveling as it scraped along the rock until a huge gouge appears where the rock punctured the hull. The hole extends back, widening for the next 6 feet along the starboard hull until it hit the bulkhead.

A gash that large could sink a boat in short order, Goodridge said.

"The boat probably rolled upside down the first night and was pushed out of the river," he said.

The foredeck of the boat popped up about half a mile from the jetty on June 27, Whipple said. After searching for the rest of the boat, they called in on Monday a boat with side scanning sonar capability, which located the debris they salvaged yesterday, about 300 to 400 yards off the north jetty, Whipple said.

Recent accounts from witnesses — one claiming that the boat appeared to attempt to jump the jetty — don't hold up, both men say, adding that the boat's condition provides the best evidence.

The perspective of the witnesses who were either on the beach or fishing on Plum Island, especially given the fog the night of the accident, appear to have been mistaken, the men said.