1914: Sir Ernest Shackleton announced in a letter in The Times that he intended to lead an expedition across Antarctica. Response was enthusiastic. Nearly 5,000 would-be polar explorers applied to accompany him. Shackleton placed their letters in three large drawers labelled “Possible”, “Hopeless” and “Mad”.
Source: Hugh Robert Mill, The Life of Sir Ernest Shackleton (1923), p. 195