Why is the term Roger Wilco considered by some to be an incorrect phrase - trivia question /questions answer / answers
Aerophones; any class of musical instruments in which a vibrating mass of air produces the initial sound including bull roarers and sirens. They are found in many countries throughout Africa and are normally incorporated with dancing, the musicians having to synchronize their footwork along with playing their notes!
Dictaphone was prominent in the provision of multi-channel recorders, used extensively in the emergency services to record emergency telephone calls (to numbers such as 911, 999, 112) and subsequent conversations.