IT WAS as a teenager carting hay in the bush outside Wagga Wagga
that Bill Gammage's lifelong curiosity about the Australian
landscape emerged. What initially puzzled him was that certain
trees were not growing in the soils that he knew best suited
them. ''It led me to all sorts of possibilities.'' One of those
possibilities turned out to be the crucial role Aboriginal
people and their deft use of fire played in shaping the
Australian environment, and for the past 12 years Gammage has
devoted most of his working life to his much lauded account, The
Biggest Estate on Earth: How Aborigines Made Australia,
published a year ago. Last night Gammage, an adjunct professor
at the Australian National University, won Australia's richest
literary prize, the $100,000 Victorian Prize for Literature,
part of the Victorian Premier's literary awards, for the book
The Age described as ''history of the most readable type … a
beautiful and profound piece of writing''. Gammage also won the
premier's non-fiction prize, worth $25,