In 1845 he published his "Physical Description of New South Wales and Van Diemen's Land" .The book gained the praise of Charles Darwin and other scientists and was awarded the Gold Medal of the Royal Geographical Society. It was an unsurpassed source of knowledge on Australia for at least forty-five years. He also published the first map of Gippsland and its description which helped to open up this fertile part of Victoria. He produced the first large geological map of Eastern Australia and Tasmania.