The Real <I>Moby Dick</I>

It is the stuff of fiction: heroic battles with the mighty whales of the Pacific, a shipwreck, a desperate struggle to stay alive while stranded on the open sea.

Fifteen months after setting sail from Massachusetts' Nantucket Island in 1819, the hunters would become the hunted as an angry sperm whale rammed the whale ship Essex, sinking the ship.

Forgotten for years, the story of the Essex has been given new life by historian Nathaniel Philbrick in his best selling book, In the Heart of the Sea: The Tragedy of the Whale Ship Essex.

In an interview for The Saturday Early Show, Philbrick describes the whale's attack: "It swam a couple of hundred yards ahead of the ship, turned around and came right after the ship at twice its original speed and rammed into the port bow of the ship, crushing in the bow as if it were an eggshell and even - according to one account - driving this 238-ton ship backwards."

Twenty crewmembers would take refuge in small whaleboats left to drift in the middle of the Pacific Ocean. Only eight would survive

The survivors headed east toward the South American shore, foregoing a much shorter journey to the Pacific islands to the west for fear of cannibals. Ironically, some would eventually resort to cannibalism to stay alive.

Philbrick's book is a compilation of narrative tales of Essex survivors, including the recently discovered notes of cabin boy Thomas Nickerson, found in the attic of a Connecticut home.

Philbrick did most of his research at the Nantucket Historical Association, which is now showing a companion exhibit to the book with some original pages of Nickerson's account, paintings of the Essex, and other artifacts from the period.

The story unfolds with a description of the brutal life on a whaling ship. The crew lived on meager portions of hard biscuit and salted meats while risking their lives pursuing a 60-ton creature that with one swipe of its mighty tail could crush the small harpoon boats deployed from the main ship.

Not only did Philbrick study whaling, he also consulted with medical doctors and experts on the effects of months of dehydration and starvation on the men left adrift under the scorching Pacific sun.

He interweaves his findings with written accounts as he describes two crewmembers' rescue after three months at sea. "Instead of greeting their rescuers with smiles of relief, the survivors - too delirious with thirst and hunger to speak - were disturbed, even frightened," writes Philbrick. "They jealously clutched the splintered and gnawed-over bones with a desperate, almost feral intensity, refusing to give them up, like two starving dogs found trapped in a pit."

Though the survivors were ostracized for eating their shipmates, it was not a unique incident in that era, Philbrick tells CBS News' Thalia Assuras. "I wasn't surprised that the me did take that final step to cannibalism because in the early 19th century, survival cannibalism was, shockingly to us, prevalent," he says.

Over the years, the tale of the Essex slowly faded into obscurity. In writing the book, Philbrick says he rediscovered the humanity of his subjects: "These men began to seem like men rather than faceless sufferers, and so you begin to see some with certain strengths, some with weaknesses and how this terrible fate played out."