Alastair Cook defied Australia's bowlers in near 40 degree heat for his second successive Ashes hundred - without breaking sweat.To another sell-out crowd at the Adelaide Oval, it was a remarkable feat to get to the bar and back in reasonable shape on a sweltering second day of this second Test.But for the England opener, that was small beer indeed.By stumps, he had spent almost 17 hours at the crease and scored a record 371 unbeaten runs since he took guard in the second innings of the first Test at the Gabba last week.Cook therefore surpassed Wally Hammond's previous English best against Australia for runs without dismissal, in the process helping to carry his team to 317 for two - already 72 in front.Read