Crystal, The Site which gave the Waterloo Cup Records has gone down the plughole otherwise I would have had some information on White Rose.
Master McGrath`s record three wins was surpassed by Fullerton a winner on four occasions, in 1889, 1890, 1891 and 92.
McGrath would likely have set a record 4 wins, but had the misfortune to fall through the ice of a small pond on the Course in 1870, he of course completed two wins in 1871 and 72 which added to his 1869 win made him the first three time winner of the Waterloo Cup, he won 36 of his 37 races.