They made camp on a large, stable-looking floe and waited for the ice to carry them north. This became known as Ocean Camp. They made trips back to the wreck to salvage additional supplies — the third lifeboat, more food, personal items — until a blizzard began carrying the floe north too rapidly to make return trips worthwhile.
A quick count of the drift: the floe moved sixteen miles in two days. They were now committed to this passage, wherever it led.
On November 21, 1915, Shackleton and several of the men watched from the ice as the Endurance finally slipped beneath the surface. McNish recorded the moment in his diary. Worsley wrote that she went down bows first, her stern lifting briefly out of the water, and then she was gone. The place she had been was covered by ice and sea within minutes, as if she had never been there at all.
The men camped on the moving ice through the southern summer. When the floe they were on cracked and began to break up, they moved to a new one. They shot and ate seals and penguins, supplementing the supplies they had saved. The cold was constant. The ice underfoot was never still. They were, in the most literal sense, adrift.
In late December, Shackleton moved the party to a new position he called Patience Camp, hoping to drift north to open water before the ice disintegrated under them. He was waiting for the mathematics of the ocean current to deliver them to where the boats could actually be launched. It was a plan based on large probabilities and smaller hopes, and it held together through two more months of camp life before the ice broke up enough to launch the boats.