Vintage photo circa 1910s of British Antarctic explorer Sir Ernest Henry Shackleton (1874 - 1922). Irish-born Shackleton served as a junior officer on Robert Falcon Scott's Discovery Expedition of 1901 - 1904 and subsequently led the Nimrod Expedition of 1907 - 1909 (also known as the British Antarctic Expedition) which reached a point closer to the geographic South Pole than had ever previously been attained. Shackleton is however probably best remembered for leading the Endurance Expedition (also known as the Imperial Trans-Antarctic Expedition) of 1914 - 1917 - an attempt to make the first land crossing of the Antarctic continent from sea to sea. Shackleton's ship Endurance became trapped in pack ice and was slowly crushed and sank - leaving her 28-man crew stranded on the ice and sparking a series of heroic actions which ultimately resulted in the survival of all the expedition members. Shackleton obtained funding for another expedition to Antarctica in 1921 but had a fatal heart attack before the expedition was properly under way. Photo by Bain News Service.