Excerpt from Shadow Divers by Robert Kurson, plus links to reviews, author biography & more

But not Nagle. In the sport's brawniest era, he was a man of the mind. He devoured academic texts, reference works, novels, blueprints, any material he could uncover on historical ships, until he could have stood in the dockyards of a dozen eras and built the boats alongside the workers. He was a connoisseur of the parts, and he reveled in the life force a boat took on from the interlocking of its pieces. This insight gave Nagle two-way vision; as much as he understood the birth of a ship, he also understood its death. Ordinary divers would come upon a shipwreck and see the mélange of bent steel and broken wood, the shock of pipe and wire as a cacophony of crap, an impediment that might be hiding a compass or some other prize. They would plant their noses in a random spot and dig like puppies, hoping to find a morsel. Viewing the same scene, Nagle repaired the broken parts in his mind and saw the ship in its glory. One of his greatest finds was a four-foot-tall brass whistle from the paddle wheeler Champion, a proud voice that had been mounted on the ship's mast and powered by a steam line. The whistle was majestic, but the most beautiful part of the discovery was that underwater it looked like a worthless pipe. Floating amid the wreckage, Nagle used his mind's eye to watch the ship break and sink. He knew the ship's anatomy, and as he imagined it coming apart he could see the whistle settle, right where that seemingly worthless piece of pipe lay. After Nagle recovered two helms from the British tanker Coimbra in a single day (finding one helm once in a career was rare enough), his photograph was hung-alongside that of Lloyd Bridges--in the wheelhouse of the Sea Hunter, a leading dive charter boat of the time. He was twenty-five.

To Nagle, the value in artifacts like the brass steam whistle lay not in their aesthetics or their monetary worth but in their symbolism. It is an odd sight to see grown men covet teacups and saucers, and build noble display cases to these dainty relics. But to divers like Nagle these trinkets represented exploration, going off the charts. A telegraph on display in a diver's living room, therefore, is much more than a shiny object; it is an announcement. It says, If someone had been to this ship's wheelhouse before me, he would not have left this telegraph behind.

It was only time before Nagle's instinct delivered him to the Andrea Doria, the Mount Everest of shipwrecks. The grand Italian passenger liner had collided with the Stockholm, a Swedish liner, in dense fog off Nantucket Island in 1956. Fifty-one people died; 1,659 were rescued before the liner sank and settled on her side at a depth of 250 feet. The Doria was not a typical target for Nagle. Her location was widely known, and she had been explored by divers since the day after her sinking. But the Doria made siren calls to great wreck divers. She was brimming with artifacts even after all these years: serving sets made of fine Italian china and painted with the ship's legendary Italia logo, silver utensils, luggage, ceramic tiles by famed artists, pewter sherbet dishes, jewelry, signs. In Nagle's day, and even today, a diver could explore the Doria and worry only about having enough stamina to lug home the prizes he recovered.

Had the Doria only her riches to offer, she could not have romanced Nagle so hopelessly. The ship's real challenge lay in exploration. The wreck rested on its side, making navigation dangerous and deceptive. A diver had to conceive the world sideways to make sense of doors on the floor and ceilings to the right. And she was deep-180 feet at her shallowest and 250 feet where she crushed the ocean floor. Men sometimes got disoriented or ran out of air or lost their minds from narcosis and died on the Doria. The wreck was so deep, dark, and dangerous that decades after her sinking, entire decks remained unexplored. Those decks were Nagle's destinations.

Excerpted from Shadow Divers by Robert Kurson Copyright© 2004 by Robert Kurson. Excerpted by permission of Random House, a division of Random House, Inc. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.