Australian Broadcasting Corporation: SIXTY-TWO-YEAR-OLD Bill McKenzie stands in the corridor on the eighth floor of the government housing complex where he lives, pointing accusingly at a thermometer fastened to the wall. He explains that at 4pm on January 17, as Melbourne sweltered through one of south-east Australia's worst heatwaves, the thermometer read 43 degrees hotter than it was outside. A short, wiry man with a shaved head, McKenzie is wearing a brown long-sleeved T-shirt, reading glasses strung around his neck. In his apartment,...