| Origin of the Boatswain's Pipe
The use of the Boatswain's pipe is almost lost in antiquity, but we know that the ancient galley slaves of Greece and Rome kept stroke by the flute or whistle.
The Pipe or Call was originally used as a badge of rank also and as such was worn by the Lord High Admiral of the Royal Navy and was known as the Whistle of Honor. It was made of gold and suspended from the neck by a gold chain.
These officers also carried a Whistle of Command, which was of silver, and was used for passing orders and blown as a salute to certain personages. It was enjoined that it should be blown on these occasions "three several times."
The first time it can be found being used to actually to pass an order was during the Crusade of 1248, when the Cross-bowmen were piped to come on deck and engage the enemy.
The present form of the bosun's pipe is actually a facsimile of that taken from the body of the infamous pirate Andrew Barton by Admiral Lord Howard.
At times the whistle seems to have been a somewhat weighty instrument. It is believed that it was Henry VIII who laid down the names of the parts of the whistle, and the weight of the Whistle of Honor was put at 12 "Oons" or ounces of gold, while the chain was to be of a certain value of golden ducats."
Click to hear some of the calls:
All Hands
Belay
Heave Around
Mess Call
Pass The Word
Piping the Side
All Secure
Source: http://home.earthlink.net/~bosun-m8/id20.html | 
