1913 (April 19) autographed letter, headed 'University of Sydney' (3 sides) from J.W. Edgeworth-David to 'Silas' Wright regarding their on-going discussions regarding 'the Barrier', 'Salinity & the open pools of water in Ross Sea..', etc. In mid-1907 Edgeworth David was invited to join Shackleton's Nimrod Expedition to the Antarctic and in December won Australian Government funding for the expedition. The same month he left for New Zealand with Leo Cotton and Douglas Mawson, two of his former students. David was nearly 50 years of age and it was intended that he would stay only until April 1908, but en route to Antarctica on the Nimrod he altered his plans and decided to stay for the whole expedition. From 5 March to 11 March 1908, David led the first ascent of Mount Erebus, the only active volcano in Antarctica. He led the summit party consisting of Mawson, Dr Alistair Mackay and himself, and there was a supporting party of three which it was afterwards decided should also attempt to reach the summit. In this they were successful in spite of a blizzard which barred their progress for a day and night. One member of the party had his feet badly frostbitten, and had to be left in camp before the final dash, but David and four others reached the summit and the whole party returned to the base.