Official referee whistle. Following on from its cousin the Metropolitan, and a year younger being born in 1884, the Thunderer came about as Joseph Hudson sought to replace the sticks and handkerchiefs football referees had used to that point for officiating matches. Whilst the police whistle required a sound that would carry, the Thunderer needed to attract the players attention over the noise of both the game and the crowd. The solution was the famous 'pea', which produced a fuller warbling sound. Still in use today, the effectiveness of this design is demonstrated from Wembley to the Maracana, Ellis Park to Murrayfield.