On 9 August 1914 the Endurance departed Plymouth, carrying Shackleton and his crew on what was intended to be the first expedition to cross Antarctica from the Atlantic to the Pacific via the South Pole. Over 5000 applications for places in the crew had been received. The expedition was a failure: the ship became trapped in pack ice and was eventually destroyed by the pressure of the ice, but all the crew of the Endurance were eventually rescued after Shackleton and five men made an 800-mile sea journey to fetch help. Clark was a hard worker, and, despite his dour manner, quickly won the respect of the crew with his willingness to volunteer for some of the more arduous or unpleasant jobs aboard ship, although he was the butt of several jokes. He was not the politest of men, and a little verse was composed around his apparent inability to remember to say "please". The crew boiled some spaghetti and placed it in one of his collecting jars, causing him momentary excitement at the thought of having discovered a new species, and a standing joke claimed the penguins seen alongside were said to shout out "Clark, Clark" and chase after the ship whenever he was at the wheel. He worked arduously at his biological recording from the moment the expeditions set out, recording the specimens encountered using dredging nets as the ship progressed southwards. When the ship became trapped in the ice he continued with his work, dissecting penguins and recording the changes in the plankton levels in sea. When the ship had to be abandoned all Clark's specimens were left behind. Frank Worsley recorded: Once they reached the edge of the pack ice the crew set out for Elephant Island in three of the small boats of the Endurance. Clark travelled in the 22½-foot James Caird with Shackleton, Frank Hurley, Leonard Hussey, Reginald James, James Wordie, Harry McNish, Charles Green, John Vincent and Timothy McCarthy. On arriving at the island, Shackleton set out almost immediately with five of the crew to fetch rescue from South Georgia. The rest of the men, Clark among them, stayed camped on the island with Frank Wild in command. Elephant Island was inhospitable. It was cold but humid which meant that neither the clothing nor the sleeping bags were ever completely dry. Though there were penguins and seals to eat, the supplies were not inexhaustible and fuel was scarce. The routine on the island was monotonous. Clark managed to produce a primitive alcoholic beverage from methylated spirit, sugar, water and ginger which became known as "Gut Rot 1916" and was drunk with a toast to "Wives and Sweethearts" on Saturdays. On 30 August 1916, the men on Elephant Island were rescued by Shackleton aboard the Chilean ship Yelcho, four months after he had left the island.
