IT IS a fact worth noting that when the explorer Ernest Shackleton, desperate to get his 28-man crew back to terra firma in 1916 after more than a year stuck in the Antarctic pack ice, was faced with reducing weight on the lifeboats, he dumped food provisions over the side rather than lose his tins of photographic glass plate negatives. The importance of these images, taken by the brilliant Australian photographer Frank Hurley, was indeed so great, that in the final push for the island of South Georgia in the small lifeboat, the James Caird, across 750 miles of hostile Southern Ocean with all but five of his exhausted men marooned on the remote, uninhabited Elephant Island, Shackleton carried, carefully wrapped against water damage, a photographic plate of his ship, the Endurance, beset in the ice. It is one of the most iconic surviving images from one of the greatest survival stories of polar exploration. When the negative was eventually published in the London papers some few months later, it foretold a rescue so improbable – all the men under Shackleton’s command were brought home alive – that it still excites awe a century later.

The importance of imagery is shown to great effect in this touring exhibition at the National Library from the British Geological Society, which holds one of the finest collections of expedition photographer Frank Hurley’s spectacular glass plate and celluloid negatives, digitised in its entirety to mark the centenary of Shackleton’s Imperial Trans-Antarctic expedition (1914-17). Images were key for Shackleton and his peers, for not only would good photographs repay the sponsors who had advanced money for the expedition on the promise of spectacular still and cine film images, it would bolster post-expeditionary talks, lectures and indeed, memoirs. Some of the best of Hurley’s images are reproduced in this exhibition on a very large scale (as the photographer had intended), a little disappointingly, perhaps, not on photographic paper but as part of the exhibition boards, although with glass plate negatives in viewers below as evocative artefacts.

Taking photographs in the Antarctic was no straightforward matter, nor was returning them safely to civilisation. Hurley, a veteran of Douglas Mawson’s Australasian Antarctic Expedition of 1911 and already a respected photographer, knew the requirements of working in freezing conditions, packing solid, reliable equipment from Graflex cameras to folding pocket Kodaks. Once the Endurance became beset in the pack ice of the Weddell Sea, just three days out of South Georgia, he repurposed the ship’s refrigerator as a dark room, and stored his fragile negatives in Shackleton’s cabin, which had the most stable temperature on the whole ship.

When the Endurance began her final break-up, Hurley spent three days salvaging what material he could from the icy waters that had begun to pour into the boat. In his later account of the expedition, “Shackleton’s Argonauts”, Hurley wrote, “We hacked our way through the splintered timbers and, after vainly fishing in the ice-laden waters with boathooks, I made up my mind to dive in after them. It was mighty cold work groping about in the mushy ice in the semi-darkness of the ship’s bowels, but I was rewarded in the end and passed out the three precious tins.” It was a short-lived success, for as the crew were forced to set out over the ice, dragging the lifeboats behind them, weight became a premium. Along with the ship’s dogs and the ship’s cat, who were shot as the expedition set off across the ice, Hurley was forced to smash some 400 of his glass negatives, saving “the best” 150.

The exhibition itself retells the expedition through the images in chronological fashion, an immersive series of photographs, with text written by polar historian Meredith Hooper. There are pictures of the ships scientists scrubbing the floor of the “Ritz”, the living quarters that the ship’s carpenter, Glaswegian Harry “Chippy” McNish, had carved out in the hold. Photos, too, of men huddled round the pot stove in the hold, Hurley capturing the glow of the stove on the faces; later, of them dragging the lifeboats over the mush of summer ice, alongside stunning moving images of the long winter on the ice.

Alongside the immersive exhibition boards are glass cases with items from the Library’s own extensive polar collections including the paperknife McNish made out of a tent peg for his friend and fellow Scot, James Wordie, a rare survival of a personal item made whilst on the Endurance. Such items are welcome pieces of real polar material in an exhibition dominated by Hurley’s wildly impressive photography.

Enduring Eye: The Antarctic Legacy of Sir Ernest Shackleton and Frank Hurley, National Library of Scotland, George IV Bridge,

Edinburgh, 0131 623 3700,, until 12 Nov, Mon-Fri, 10am–8pm; Sat 10am–5pm; Sun 2pm–5pm