Sir Ernest Shackleton's final polar expedition was also his most ambitious. In 1915, he and his crew set off aboard the Endurance with the goal of becoming the first men to cross the Antarctic continent. Though ultimately unsuccessful, their mission lasted 21 months from departure to return. Luckily, Shackleton had plenty of books on board to pass the time, the BBC reports.

London's Royal Geographical Society recently digitized a photograph taken aboard the Endurance in March 1915. The image shows the explorer's collection of reading material, and thanks to digital enhancement, their titles are visible for the first time. We now know that Shackleton brought dictionaries and encyclopedias with him as well as famous works of literature. Some of the notable titles include The Brothers Karamazov by Fyodor Dostoyevsky, the Poetical Works of Shelley and Almayer's Folly by Joseph Conrad. He also brought with him a number of tomes detailing polar expeditions from the past, like Voyage to the Polar Sea and Journal of HMS Enterprise.

The frame hanging on the wall at the left side of the picture contains a print of Rudyard Kipling's poem "If." According to the Royal Geographical Society, Shackleton carried the poem with him onto a sheet of floating ice while fleeing his sinking ship. 

The Endurance remained trapped in ice for 10 months before ultimately sinking into the sea, forcing the crew to transfer to the ship's three lifeboats. It was months before they finally found help, but Shackleton was able to lead all 28 members of his crew to safety. The expedition is chronicled in Ernest Shackleton's 1919 book South. To see the full list of titles the explorer brought on board, check out the original article on the BBC.

[h/t BBC]