Falling Whistles
Falling Whistles sells whistles for $34 to $104 to raise money for education, advocacy, and the rehabilitation of war-affected people in Congo. The organization got its name from a journal written by its founder, sharing his experiences during a trip to eastern Congo in 2008. During that trip, Falling Whistles' founder met a group of five former child soldiers who told him that some children who were too young to carry weapons were sent into battle armed only with whistles. By wearing whistles, the campaign aims to use this weapon as a tool of protest and to raise awareness of the situation in Congo. As of September 2010, $500,000 has been raised.
Tin whistle
The whistle is tuned diatonically, which allows it to be used to easily play music in two major keys a perfect fourth apart and the natural minor key and Dorian mode a major second above the lowest note. The whistle is identified by its lowest note, which is the tonic of the lower of two major keys whose tonics are a perfect fourth apart that the whistle most easily plays in. Note that this method of determining the key of the instrument is different from the method used to determine the key of a chromatic instrument, which is based on the relationship between notes on a score and sounded pitch. Whistles are available in a wide variety of different keys.