Why was the captain of the Bounty so desperate to save the ship's chronometer? Timepiece that held the key to the most infamous mutiny in British naval history Captain William Bligh was kicked off the Bounty by mutinous crew in 1789 During revolt, he pleaded to keep hold of K2, the ship's chronometer But mutineers refused to hand it over and used it to flee to Pitcairn Island New letter reveals how Bligh had to admit to the Admiralty it had been lost Valued: K2, the maritime time-keeping device, used by Captain William Bligh on board the Bounty Dragged from his cabin, bewildered and wearing only a nightdress, Captain William Bligh of the HMS Bounty was facing a nightmarish scenario. Half of his ship's crew, emboldened by the rallying cries of traitorous first mate Fletcher Christian, were in mutiny. About to be cast off by his own men, his thoughts must have been panicked - stranded more than 1,300 west of Tahiti, his prospects of survival appeared bleak. And yet, in the midst of one of the most notorious incidents in British naval history, Captain Bligh did not plead for his life. Instead, he demanded the mutineers hand over the ship's chronometer. Alongside his clerk John Samuel, Bligh pleaded with the mutineers to let him take K2, a timekeeping device that allowed the crew to determine their longitude. Documents held by the University of Cambridge reveal for the first time how Bligh interrupted the chaotic mutiny in 1789 to try and save the valued timepiece. In his account of events he wrote: 'Mr Samuel attempted to save the time-keeper but he was hurried away by the mutineers with: "Damn your eyes: you are well off to get what you have."' Why was Captain Bligh, facing such unprecedented catastrophe, so desperate to leave with the chronometer? Admission: Captain Bligh's letter to the Admiralty explaining that the chronometer was 'pirated from my command' Dire straits: An illustration of the 1789 mutiny on the Bounty when half Captain's Bligh's crew rose up against him and cast him off the ship Was it a symbolic gesture, did he simply wish to cling on to something which helped maintain a sense of order? The answer may in fact have been much less romantic. The chronometer was worth a serious amount of money. Bligh had made a promise to the Admiralty that he would look after K2 which had cost £200 (around £11,000 in today's money). At loggerheads: Captain Bligh, left, was dragged from his cabin in the middle of the night by first mate Fletcher Christian, right, and his band of mutineers He wrote to the Board of Longitude on October 18, 1787, acknowledging receipt of the device 'which I promise to return to (the maker) on their order or demand.' And K2's value was more than just monetary, in 18th Century seafaring it was a key tool of survival. Fed up with Bligh's floggings and hungry to return to the kind of idyllic life they had enjoyed in Tahiti, Christian and his mutineers lowered the deposed captain and his loyalists into a rowing boat and left them for dead. They then used K2 to navigate their way to Pitcairn Island which they believed would be the perfect place to hide out. Simon Schaffer, Professor of History at Cambridge University, told The Times that the watch enabled the crew to work out that Pitcairn was inaccurately marked on the Admiralty's maps. They then set fire to the Bounty to cover their tracks. Land ahoy: After having been cast adrift, Bligh and his crew were hospitably received by the Governor of Timor Meanwhile, despite having lost the crucial piece of technology, Captain Bligh was able to complete a remarkable 47-day voyage to Timor in the Dutch East Indies. On October 27, 1790, he wrote to the Admiralty admitting that K2 was no longer in his possession. 'I am to inform you the the Time Keeper, which was given to my charge on board His Majesty's Ship Bounty, was left in the said ship when pirate from my command on the 28th April, 1789.' The crimes of the mutineers caught up with them two years later when, after news reached Britain, a ship was dispatched to arrest them. After rounding up 14 out of 23 of the mutineers, they were imprisoned in a makeshift cell on the deck of HMS Pandora. Four died along with 31 crewmen when the ship ran aground on the Great Barrier Reef, but the remaining ten prisoners were returned to Britain to face court martial in Portsmouth. K2's journey of high drama was far from over. It remained on Pitcairn Island with the mutineers until 1808 when it was bought by an American whaler named Mayhew Folger who bought it and travelled on to Valpariso, Chile. When Folger ended up in prison the chronometer was confiscated by the governor before it passed through the hands of a Spanish mule trader and a Royal Navy captain. Eventually it ended up with the Royal United Services Institution which allowed it to return to the Royal Greenwich Museum in the 1960s where it remains today.