BIRMINGHAM: Alastair Cook's double century ensured there was no let-up for India on the third day of the third Test at Edgbaston here on Friday.England were 503 for three when rain forced an early lunch.That meant England were 279 runs ahead in a fixture where a win would both secure an unbeatable 3-0 lead in this four-match series and see them replace India at the top of the ICC's Test Championship table.Cook was 206 not out and Eoin Morgan 66 not out, with India failing to take a wicket in a session twice interrupted by rain.The left-handers unbroken fourth-wicket partnership was now worth 129 with opener Cook having spent more than nine hours at the crease in an innings where bad weather, as much as India's attack, looked the best way of checking England's otherwise remorseless progress.England resumed Friday in the already commanding position of 456 for three in reply to India's first innings 224.Cook, whose 19th Test century left the 26-year-old opener just three shy of equalling the England record, was 182 not out and Morgan, dropped twice off easy chances Thursday, 44 not out.Only persevering and skilled medium-pacer Praveen Kumar, one of India's few success stories on an injury-hit tour, had maintained a measure of control Thursday with two for 75 in 32 overs.But Morgan's square-driven four off Kumar on Friday took him to 49 and a single off the seamer saw the former Ireland international to a 73-ball fifty with seven boundaries. Then, after a 26-minute rain break, Cook and Morgan completed England's eighth century stand of the series.Cook had a scare on 197 when Kumar swung one late and nearly bowled him around his pads.But a leg-side clip for two off fast bowler Shathakumaran Sreesanth took Cook to the second Test double century of his career, following his 235 not out against Australia at Brisbane in November, in 378 balls with 27 fours.