Whistles made of bone or wood have been used for thousands of years for spiritual, practical, and entertainment purposes. One of the most distinctive whistles is the boatswain's pipe used aboard naval vessels to issue commands and salute dignitaries. It has evolved from pipes used in ancient Greece and Rome to keep the stroke of galley slaves.
A medieval version was used during the Crusades to assemble English crossbow men on deck for an attack. The model currently being produced by the Acme Whistle Company of Birmingham, England, was first manufactured in by the company's founder, Joseph Hudson. The modern era of whistle use began in when a whistle was first blown by a referee during a sporting event. Hudson, a toolmaker who was fascinated with whistles, fashioned a brass instrument that was used in a match at the Nottingham Forest Soccer Club.
This device was found to be superior to the usual referee's signal of waving a handkerchief. In , the London police force made it known that it was seeking an alternative noisemaker to replace the heavy, cumbersome hand rattle the officers had been using. Hudson invented a light, compact whistle that produced two discordant tones that could be heard for more than a mile.
It was immediately adopted and the same design is still in use today. The following year, Hudson invented the "pea whistle. The pea whistle remains the world's largest-selling type. Manufactured whistles are made of either metal or plastic. The only metal whistles manufactured in the United States are made of brass an alloy of copper and zinc ; the fact that they are nickel or chrome plated gives rise to a common misconception that they are made of steel.
Brass is used because of the same tone and resonance qualities that make it effective in musical instruments. Despite common terminology, the ball contained in pea whistles is actually made of cork except for inexpensive, plastic versions. American Whistle Corporation has developed a synthetic cork material that behaves like natural cork in every respect except that it does not absorb any moisture. This helps keep the ball from getting stuck inside the whistle and not swirling freely. Because metal whistles are hard and subject to temperature fluctuations in very hot or cold weather, rubber mouthpieces are manufactured as an optional accessory.
Besides providing a cushioned mouth grip and a reliably comfortable temperature, the accessory also provides a mechanism for adding color to the metal whistle. Plastic whistles were first manufactured in Britain in , after earlier attempts to produce a satisfactory model from vulcanite hardened rubber had failed.
This allowed design variations and colors that became popular with consumers. The components of modern plastic whistles may be either glued or ultrasonically welded together. The following process is used to manufacture the type of metal pea whistle that is commonly associated with American military, police, and sports applications.
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. A jam-up means no vibration, no sound, no communication.
The ingeniously-designed Fox 40 whistle doesn't use a pea to generate sound. In fact, there are no moving parts whatsoever. Nothing to obstruct sound, nothing to stick, freeze or fail. Fox 40's patented design moves the air blast through specifically tuned chambers.
The whistle that works in all conditions Pull a Fox 40 out of the water and its flow-through chambers drain instantly.
0コメント