ATLANTIC CITY — The violent crash came without warning just after 2 a.m. on a cloudy and breezy morning off the coast of Atlantic City in 1860.

The Robert J. Walker, a government steamboat surveying the coast, was hit hard by a passing commercial schooner that accidentally ripped a gash in the side of the ship and fled into the darkness.

Most of the Walker’s crew of nearly 70 jumped from their beds and tried to save the steamer. They steered the ship toward the nearest light, Absecon Lighthouse on the Jersey coast. But it was too late. Within a half hour, the Walker sunk. Twenty men clinging to the wreckage eventually went down with it.

"I cannot withhold … profound regret for the melancholy fate of that portion of the crew who are still missing and who it is to be feared have found a watery grave," Lt. John Guthrie, the Walker’s captain, and one of the last rescued from the water, told his bosses in a telegram a few days later.

Then … nothing happened. With the start of the Civil War approaching, the government never investigated the disaster. No one on the schooner was ever prosecuted. No memorial was held for the 20 dead men or another who died when he reached shore.

For more than 150 years, the Walker sat at the bottom of the Atlantic Ocean, 10 nautical miles off the Jersey Shore, all but forgotten.

Until now.

Last summer, the National Oceanic and Atmospheric Administration announced it had identified the remains of the Walker 85 feet beneath the surface at a mysterious site that had been popular with Jersey Shore fishermen and divers for decades. NOAA, the government agency that succeeded the old U.S. Coast Survey agency that operated the Walker, said it wanted to honor the men who died in the shipwreck. But the agency also wanted to learn more about the site and continue to open it to divers.

This summer, students and researchers from Richard Stockton College in nearby Galloway are using sonar and other equipment to map the complex wreck. Their work will provide the first detailed look at the deadliest disaster in NOAA’s history.

"I'm delighted, as are the other folks at NOAA, to see both the involvement of the New Jersey wreck-diving community and the students and faculty at Stockton College," said James Delgado, director of maritime heritage in

NOAA's Office of National Marine Sanctuaries.

In 1852, W.A.K. Martin painted this picture of the Robert J. Walker. The painting is now at the Mariner's Museum in Newport News, Va. Richard Stockton College students are mapping the remains of the Walker, which sank off the Atlantic City coast in 1860.

SHARED BENEFITS

"Archaeology is about people, and a wreck like Walker is part of our common heritage as Americans," Delgado said. "It’s something to be shared for the benefit of all, for the story to be told, and for the loss of the 21 men on the ship to be remembered."

The Stockton students, who are enrolled in a summer course titled the Summer Intensive Research Experience, have been taking weekly trips to the wreckage site in a small research boat. They are using advanced multi-beam sonar technology and geographic information system software to define the size, depth and location of the shipwreck.

"It sounded like fun, and it is," said Walter Poff, 25, a marine science major from Blackwood. "It’s definitely the most interesting summer class available."

Underwater video of the site shows much of the Walker, one of the U.S. government’s first iron-hulled steamers, has survived after more than a century under the sea. The ship’s hull, unique engines, paddle wheel and rectangular portholes remain nearly intact and helped identify the wreckage as belonging to the Walker.

The ship is still pointing toward Absecon Lighthouse, the beacon the crew had raced to reach in the dark before the Walker sunk.

Richard Stockton College student Chelsea Shields, right, takes notes while biology professor Peter Straub helps map a shipwreck 12 miles off the coast of Atlantic City. In 1860, the steamship Robert J. Walker collided with another vessel and sank, killing 20 people. More than 150 years later, Stockton College students are returning to the deadly site to map the shipwreck using sonar and other high-tech equipment. The wreck, recently named a national historic site, has become a popular spot for divers.

ACOUSTIC PICTURES

For the Stockton students, the mapping work is labor intensive. The students and the team of researchers often spend six hours at a time on their research boat, traveling through the Great Bay, north of Atlantic City, to the site of the Walker. The students operate the multi-beam sonar to receive an "acoustic" picture of the wreckage, then take the data back to their lab.

"The students on this project are using hands-on technology, the same that they’re using to search for the missing Malaysian Airline flight (Flight 370 in the southern Indian Ocean)," said Stephen Nagiewicz, a veteran diver and shipwreck explorer who is serving as exhibition leader for the Stockton project.

Chelsea Shields, one of the marine science majors in the class, said every hour of data is equal to 30 hours of post-processing work that the researchers must perform on computers in the lab.

"Everyone thinks marine biology is such a glamorous job — it’s not," said Shields, 19, of Mays Landing. "It’s a lot of hard work. We keep a mission log every day and have mini-assignments, like post-processing and editing sonar data. You have to really like this to do it."

The National Oceanic and Atmospheric Administration used various criteria, including the ship's unique paddle wheel flanges, to confirm the shipwreck near Atlantic City is the remains of the Walker steamship that sank in 1860.

PHYSICAL DATA

The students and their teacher, Stockton biology professor Peter Straub, are preparing to turn their mapping data over to the New Jersey Historical Divers Association, a nonprofit group dedicated to preserving the state’s shipwrecks. The group will use the students’ data as a reference to dive to the wreck and physically measure the remains.

The students are also taking advantage of the mapping equipment and their time at sea to do other projects, including tracking the coverage of sea grass beds and measuring sediment in the area.

"Learning how to collect this data, as well as process it, is a huge thing," said Jamie Taylor, 23, a marine science major from Berlin. "Getting that maritime experience — it’s been awesome."

NOAA officials said they are happy to see something positive coming out of a nearly forgotten disaster.

"Working with the community to better explain not only the story of the ship, but what exactly lies below the ocean off Atlantic City is important," said Delgado. "The students get a hands-on opportunity to work with history, to explore and learn in their own backyard, and in doing so, recognize that exploration can still happen."

Star-Ledger staff writer Kelly Heyboer contributed to this report.

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