In May 1891 David was appointed Professor of Geology at the University of Sydney, a post he occupied until resignation in 1924, although he continued to work at the University until his death. Although David became renowned as a teacher, and influenced many future leaders in the Australian geological community, his fame in the general community was the result of several periods away from the University.
In 1897 he directed drilling at Funafuti Atoll to try and verify Darwin's theory of the formation of coral atolls, reaching 340m in difficult conditions, the results supporting, but not definitely proving, Darwin's ideas. In December 1907 David, with former students Douglas Mawson and Leo Cotton joined Ernest Shackleton's Antarctic expedition. David led a party, including Mawson, on the first successful attempt to climb the active volcano, Mt. Erebus (3794m). David, Mawson and Forbes McKay then made a four months journey to reach the South Magnetic Pole. These Antarctic exploits made David a folk hero.
This image was enhanced when David went to the Western Front with the Australian Mining Corps in 1916. Here he was engaged in geological advice that produced dramatic results for the allies, and which again were very newsworthy. On returning to Australia David set out to write a Geology of the Commonwealth, but never completed it, thanks to numerous diversions, particularly his search for evidence of Precambrian fossils, mainly in South Australia. However his Geological Map of the Commonwealth was published in 1932, accompanied by a superb summary of the geology, written in just a few weeks.
David's contribution to Australian geology, through teaching, research, public appearances and popular writing was, and continues to be, unequalled. He is commemorated through the Royal Society of New South Wales' Edgeworth David Medal awarded annually to young scientists for distinguished contributions to science in Australia.