Most of us have read Moby Dick at one time or the other and are familiar with Herman Melville's story of a ship captain named Ahab who seeks vengeance against a white whale. The book is an American classic and is memorable for the consequences of Ahab's actions which result in the deaths of everyone except the narrator, Ishmael.

But what many don't know is that the true story that inspired it was so shocking, Melville was forced to leave out the goriest details from his book.

In 1819, the whaleship Essex set out for a whaling expedition, that was expected to take two and a half years. Just two days after it set off, a storm hit the ship, damaging parts of it.

When the Essex finally arrived at the whaling grounds, they found the waters were all fished out. So the 20-man crew set off even further than they had expected, to the South Pacific Ocean.  With experienced men on board, and a 'lucky' ship, nothing could possibly go wrong. Or so they thought.

At first, it seemed as though this was going to be a prosperous voyage. The crew had harpooned a couple whales and were expecting to find more.

But in November 1820, the first mate spotted an 85 foot whale "coming down for us at great celerity". It smashed into the ship, creating a hole in the bottom.

As the crew worked to repair it, the whale came for them again, this time, sinking the ship completely. The entire crew survived and were hopeful that they could find their way home in three boats.

With their food supply, they expected to have two months worth of rations, by which time they would hope to land on an island in the Pacific. But things were about to take a darker turn.

Salt water ruined most of their food, severely depleting rations. When the first crew member died, he was given a proper burial. But soon the starving men were eating their shoes out of desperation. Dehydration meant their tongues had swelled up and their eyes had began to weep tears of blood.

When the second man died, they buried his heart and ate the rest of his body. One after the other, the men who died were cooked and eaten.

But even this presented another problem. Whilst the survivors were still starving, no one was dying anymore. Tragically, the crew resorted to casting lots. The man who drew the black lot would be killed and eaten.  

A 17-year-old boy named Owen Coffin drew the black lot and bravely accepted his death. He was shot and quickly eaten.  

Days later another crew member died and the remaining men survived by gnawing on his and Coffin's bones. In 1821, an American whale ship spotted two men on a boat, sucking on human bones. By now, they were covered in blood and sores and were so manic, they didn't know who they were.

Five more crew members were rescued afterwards, three from another boat and two from an island.

After 93 days adrift, they had eaten seven crew members and had sailed over 4,000 miles. Melville heard the story of the Essex when on a whale ship himself, and the rest was literary history.

Do you think the survivors of the Essex were right to eat their fellow crew members to survive?