Whistles can take a number of shapes and forms. They can be made from different materials, such as metal, wood or plastic. Even the pipes in a pipe organ are essentially whistles. Despite these differences, basically all whistles work alike. What happens when air is blown into a whistle is a complicated mathematical equation. But here are the basics. Air enters the whistle at one end. As the air reaches the other, closed end, all the air molecules "pile up" on top of each other and cause a high-pressure region. The air escapes out the little hole in the end, making the noise you hear. The frequency of the sound is dependent on the length of the whistle. The longer the whistle, the lower the pitch will be. The ball inside the whistle is not necessary for the whistle to work but serves a purpose. A whistle without a ball has a flat tone that may get "lost". The Victorian Police Rattle Mystery". The Constabulary. 2003. Archived from the original on 18 February 2005 . Retrieved 30 June 2022. Cross, David (17 February 2011). "On the Beat in Birmingham - Rules and regulations". BBC . Retrieved 11 March 2014. Police whistles came much later; the early Victorian constable would have carried a small wooden rattle. Chanaud, Robert C. (1970). "Observations of Oscillatory Radial Flow between a Fixed Disk and a Free Disk". The Journal of the Acoustical Society of America. 47 (5B): 1471–2. Bibcode: 1970ASAJ...47.1471C. doi: 10.1121/1.1912065. Following an injury, should the whistle be used indicate play restarting, if the restart is a dropped ball?

e) It is for the referee, and not the touch judge, to decide whether or not the ball was thrown in from the correct place. a) The referee is the sole judge of fact and of law during a match. The referee must apply fairly all the Laws of the Game in every match. g) The referee must blow the whistle when it would be dangerous to let play continue. This includes when a scrum collapses, or when a front-row player is lifted into the air or is forced upwards out of a scrum, or when it is probable that a player has been seriously injured. Wikipedia articles incorporating a citation from the 1911 Encyclopaedia Britannica with Wikisource referencea) The referee must carry a whistle and blow the whistle to indicate the beginning and end of each half of the match. a) The referee may consult with touch judges in regard to matters relating to their duties, the law relating to foul play, or timekeeping. Exception 1: When the player throwing in puts any part of either foot in the field-of-play, the touch judge keeps the flag up. c) Signalling touch. When the ball or the ball-carrier has gone into touch, the touch judge must hold up the flag. The touch judge must stand at the place of throw-in and point to the team entitled to throw in. The touch judge must also signal when the ball or the ball carrier has gone into touch-in-goal.

Just following advice a ref got yesterday, I challenged it, but the observer was certain no whistle for DB restart. e) The referee must blow the whistle when the ball has gone out of play, or when it has become unplayable, or when a penalty is awarded. If a player has been sent-off following a touch judge’s signal, the touch judge submits a written report about the incident to the referee as soon as possible after the match and provides it to the match organiser. The match organiser may nominate a person to act as a replacement for the referee or the touch judges. This person is called the reserve touch judge and stands in the perimeter area. The referee judges what would have happened next and awards a try or a touchdown at the place where the ball was touched.Exception 2: When the team not entitled to throw-in has done so, the touch judge keeps the flag up. g) The referee gives permission to each of the coaches to enter the playing area at half time to attend their teams during the interval. Joseph Hudson set up J Hudson & Co in Birmingham in 1870. With his younger brother James, he designed the "Acme City" brass whistle. This became the first referee whistle used at association football matches during the 1878–79 Football Association Cup match between Nottingham Forest and Sheffield. Prior to the introduction of the whistle, handkerchiefs were used by the umpires to signal to the players. [5] A police whistle being blown