Davy Jones Meets the Computer

By Janice Castro

Treasure hunters use electronics to find their fortunes

Diver Joseph Amaral was groping in the blackness 80 ft. below the surface of the Atlantic early this month, collecting musket balls and other artifacts from an 18th century shipwreck, when something glistened near him in the sand. A plain gold ring, the find seemed unexceptional at first in a treasure site scattered with gold doubloons, pieces of eight and other booty. But then a crew member noticed the inscription inside the ring: "In memory of my belov'd brother, Capt. John Drew, drown'd 11 Jan. 1798, aged 47." The ring had belonged to Captain James Drew, who died just four months later when his own vessel, the De Braak, sank two miles from Lewes, Del., during a storm. This meant Amaral, 35, had proof that the wreck being explored was indeed the legendary British warship that preyed on the vessels of Napoleon's allies and when it went down, was reportedly loaded with gold bullion, jewels and gold and silver coins.

Finding a ring lost in the ocean would seem almost impossible. But according to Amaral's employer, Commercial Salvager Harvey Harrington, locating the ship was actually "embarrassingly easy." At least seven earlier expeditions had failed to find it. By contrast, Harrington's company, Sub-Sal of Reno, Nev., pinpointed the site in just three weeks last April, thanks to state-of-the-art devices that are making treasure hunters both more scientific and more successful. Where once these undersea detectives took a wild plunge with ancient charts and a hunch, the modern salvage team can reduce the search area to the site of a small lake, and hunt for pieces of gold no bigger than a pencil eraser.

Sub-Sal spent $75,000 to find the wreck, and will spend a million more to complete the salvage. The payoff: $5 million to perhaps $500 million, of which Delaware will claim 25%. About $50,000 of the salvor's initial investment went for one indispensable tool: side-scanning sonar of the type used by U.S. Navy ships searching for Korean Air Lines Flight 007 in the Sea of Japan last year. Mounted in a torpedo-shaped housing, the side-scanner emits pulses horizontally as well as vertically. It is towed behind a search ship, which methodically crisscrosses a designated area, to produce a detailed chart of the sea floor. By studying the "hits" on charts, an experienced technician can pick out possible ship ruins. "We found eleven targets in the first two days," says Harrington. His divers then went down to investigate; the fifth wreck they checked was the De Braak, the object of their hunt.

The De Braak is a spectacular new find, but scarcely the only one. Other salvors are finding sunken treasure by using computerized navigational devices and techniques developed for oil exploration and military navigation. Magnetometers, often used to detect ferrous metals, can pinpoint such common shipboard fittings as iron nails, barrel staves and anchors.

Trailed behind a ship like a side-scanner, a magnetometer will record such objects even if they are buried in sediment.

The sea-searching mini-industry is so busy that it supports various suppliers and tinkerers who refine and redesign electronic devices and other equipment to meet the special challenges of salvaging.

One of the largest operators, Treasure Salvors of Florida, uses a specially designed high-speed magnetometer. Because it can move four times as fast as a normal instrument, the company has been able to cover 240,000 smiles of seabed with unusual speed and thoroughness.

Treasure Salvors has already brought up at least $27 million worth of gold, precious gems and artifacts from the wrecks of the Spanish galleons Santa Margarita and Atocha, which sank in 1622. The company found the sister ships in waters about 50 ft. deep off the Florida Keys. During the continuing quest to trace the path of debris scattered as the ships broke apart, Treasure Salvors has videotaped the search area from the air; the shallowness and clarity of the water enable detection of such important visual clues as scars on underwater reefs.

Finding the wrecks is often only the start. Sophisticated recovery techniques are needed to get at the loot. Various blowers are sometimes used to dislodge sand. The airlift, a sort of giant vacuum cleaner attached to the search ship via a long plastic tube, removes layers of sediment while divers sift for treasure. Diving methods developed for undersea commercial uses, such as seabed mining and pipeline building, have made it possible to salvage deep-water wrecks. A notable example: H.M.S. Edinburgh, a British cruiser that sank after a Nazi attack in the Barents Sea north of Murmansk, U.S.S.R., during World War II. The Edinburgh was located with sonar devices in 1981. Then, in what the London Sunday Times called "the greatest salvage operation in the annals of the sea," British salvors brought up most of her five-ton cargo of gold from icy waters 800 ft. deep. Hot water was constantly circulated through their diving suits to ease the extreme cold.

Such an operation, like those that located the De Braak and other recent finds, rolls back the long-held secrets of the deep. One measure of how far the salvage trade has come is that when the De Braak sank 186 years ago, salvage was impossible, even though her masts were visible above the surface for more than a year to mark her grave.

--By Janice Castro.

Reported by Jamie Murphy/New York and Jane O'Reilly/Key West

With reporting by Jamie Murphy/New York, Jane O'Reilly/Key West