William had six rides in the Grand National: all were outsiders bar Frigate, on which he finished second in 1888. Willie might have won that day but, sharing the lead with his brother Harry, Harry's mount, Usna, dislocated a shoulder on landing over the Canal Turn and veered sharply to the right, carrying Frigate, with him.
William was beaten ten lengths into second behind Playfair.
Somewhat ironically, Frigate was the mare that his brother Tommy would win the following year's National.
Willie's National debut had come in 1879 when, joining his three brothers, he finished eighth on the outsider, Lord Marcus.
He didn't compete again for seven years when he was back at Aintree in 1886 on Lord Tempest, once more finishing eighth. He fell the following year on 100-1 chance The Hunter before finishing seventh the next year on The Fawn.
In 1892 he came sixth on Flying Column.
Just six weeks later, William Beasley was killed when falling from his horse, All's Well, in the Kildare Hunt Plate at Punchestown on May 9, 1892.
Willie was the champion Irish amateur jockey in 1881 & 1882.
