In 1901, the Burberry Equestrian Knight logo was developed containing the Latin word Prorsum, meaning forwards, and later registered it as a trademark in 1909. In 1911, the company became the outfitters for Roald Amundsen, the first man to reach the South Pole, and Ernest Shackleton, who led a 1914 expedition to cross Antarctica. A Burberry gabardine jacket was worn by George Mallory on his attempt on Mount Everest in 1924.