The first of the gold rushes was the most dramatic. In the decade following the original discoveries, 600,000 immigrants settled in the Australian colonies, taking the non-Aboriginal population to 1,152,000 by 1861; estimates of the Aboriginal population in that year range up to 180,000. While Victoria grew fastest, from 77,000 to 539,000, all the mainland colonies doubled in size. The challenge Victoria faced as its richest alluvial fields were worked out was to stem the outflow of prospectors and consolidate local industries that had sprung up to serve their needs. The other colonies competed for labour and capital to fulfil their own aspirations. They made rapid strides. Stimulated by a high rate of fertility and further migration, which brought nearly 750,000 additional settlers, the country’s population reached 3,174,000 by 1891. Half lived in towns and cities, among which Melbourne (473,000), Sydney (400,000) and Adelaide (117,000) accounted for more than one third of their colonial populations. The consolidation of settlement in the south-east corner of the continent was accompanied by a push into the north: separated from New South Wales in 1859, Queensland’s population grew over the three decades from 30,000 to 394,000. Economic progress outstripped the increase in population and gross domestic product increased more than threefold; the annual rate of economic growth averaged 4.8 per cent.