Enormous chunks of ice framing the Endurance stuck within a ice jam in the distance. Endurance was the three-masted barquentine in which Ernest Shackleton sailed for the Antarctic on the 1914 Imperial Trans-Antarctic Expedition. She was within 200 miles of her destination, Vahsel Bay, when heavy pack ice was sighted and a gale developed. She took shelter under the lee of a large grounded berg. On January 18 the gale began to moderate and the pack had blown away. Progress was made until hours later Endurance encountered the pack again. By January 24, the wind had compressed the ice in the whole Weddell Sea against the land. Endurance was icebound. All that could be done was to wait for a southerly gale that would start pushing, decompressing and opening the ice in the other direction. The changing conditions of the Antarctic spring brought such pressure that broke the hull of Endurance causing flooding of interior spaces. On the morning of November 21, 1915, her bow began to sink under the ice and had to be abandoned.