Chapter V: Semaphores
Some codes are used to make sending messages faster and more reliable. Before there was telegraph or telephone, the fastest way to send a message over a distance was by horse.
In 1775 the American revolutionaries learnt that the British were going to attack Concord and wanted to know which route they would take. A plan was set up whereby lights could be hung in the steeple of the Old North Church in Boston with the rule One if by land, two if by sea. The British chose to go by sea and two lights were lit that could be seen from the other shore. Thus the rebels were warned and managed to thwart the attack.
|
Old North Church
|
Semaphore is a system of signaling using flags introduced in the 1790's. The word semaphore comes from the greek words meaning sign and to-bear or sign-bearer.
The system was developed in France by Claude Chappe and his brothers. This was the time of the French Revolution and there was a great need for the government to be able to quickly communicate orders and to receive information. Their first message, on March 2, 1791 was sent a distance of 10 miles and read:
"If you succeed, you will soon bask in glory".
('Si vous reussissez, vous serez bientot couvert de glorie")
('Si vous reussissez, vous serez bientot couvert de glorie")
They used black and white flags initially, as well as clocks, codebooks and telescopes.
Over the next few years, the Chappe bothers set up a network of 556 stations around France and towers with large, moveable wooden arms were developed. The system was expensive to operate, requiring people to 'man' each station continuously during the hours of daylight. The staff had to be very skilled and attentive in order for the system to work. Once the success of the system was realized, many other countries adopted the semaphore system, including Sweden, England and Germany.
The system of handheld flags was further developed during the early 1800s when the maritime industry found that the flags were a fast and easy method to communicate between ships. It is still an accepted form of communication during an emergency, using flags in the daytime and torches at night.
The system of handheld flags was further developed during the early 1800s when the maritime industry found that the flags were a fast and easy method to communicate between ships. It is still an accepted form of communication during an emergency, using flags in the daytime and torches at night.