Following Hudson's success with the 'Metropolitan' police whistle, 1884 saw the launch of football's famous 'Acme Thunderer', a pea whistle which was widely used for sporting events. Prior to the use of a whistle, referees attracted players' attention by waving a handkerchief. The Thunderer became, and remains, the world's most popular and best selling pea whistle. Other lines developed by Hudson & Co include the 'Acme Siren', sometimes known as the cyclist's road clearer, introduced and patented in 1895; a range of bird calls, starting with a brass reeded duck call of 1888; and the 'Acme Silent Dog Whistle', invented in 1935, which was the first 'noiseless' dog whistle.Hudson & Co continue to make high quality whistles in the Jewellery Quarter today, with 125 years of whistle manufacturing history.