On the Road to the Internet: The Optical Telegraph
Communication. It’s the glue that holds societies together. We communicate through written words, spoken language, visual images, moving pictures, experiences, and more. Humans are always developing new forms and ways to communicate with each other. It’s difficult to understand the importance of communication. In an attempt to explain this importance, remember that communication is often considered a basic human right. Most modern governments recognize and provide this right.
Article 19 of the United Nations’ Universal Declaration of Human Rights:
“Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers” (“Universal Declaration of Human Rights.”).
The 1st amendment of the Constitution of the United States of America:
“Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances” (“First Amendment.”).
Communication has served a vital function in history, in both modern and ancient times. In the book of Genesis, God used communication confusion to disperse the nations and even populate the entire globe: “‘Come, let Us go down there and confuse their language so that they will not understand one another’s speech.’ So from there the Lord scattered them over the face of the whole earth, and they stopped building the city” (HCSB, Genesis 11:7–8).
Communication has won wars, caused wars, shaped our cultures, built history, altered history, and continues to shape every aspect of life on Earth.
The Internet is one of the most recent communication innovations. The road that led us to the Internet has been long and winding. To properly understand the Internet we must travel this road. One of the first stops, just feet from the beginning of the road, was the development of long-range communication.
Until the late 1700s, the speed of communication was rather limited. In order to communicate beyond the limits of one’s immediate physical proximity, one was required to travel. Later, postal systems and messengers carried our messages for us. However, they often traveled on horseback and were limited to speeds of roughly 10km/h (Sin Chan, “A brief history…”). However, maintaining this speed required the rider to push his horse and of course rest at least once a day, maybe for multiple days at a time. This system survived for many years, decades, and across centuries.
Slowly, many began to dream of true long-range communication systems that would be faster and safer and not even require a horse. Native Americans and other indigenous people groups around the world often used smoke signals. This method of communication required devising symbols represented by smoke, creating a source for the smoke, and something to control the smoke. Although effective, smoke signals are cumbersome and difficult, and can be seen for miles, which presents obvious issues for military use.
In the 1790s, an out-of-work engineer by the name of Claude Chappe developed, tested, and worked to implement the first robust mechanical long-range communication system.
On March 2, 1791, Claude demonstrated the optical telegraph with his brothers Pierre Francois, Rene, and Abraham.
They sent the message, “If you succeed, you will soon bask in glory,” over 14 kilometers in 9 minutes (Norman, “The Optical Telegraph…”). Their system, which came to be known as the Semaphore Telegraph System, depended upon visual towers stretching across the countryside (Sin Chan, “A brief history…”).
Chappe’s system revolutionized the world of communication, placing plenty of horses in the unemployment line. With the optical telegraph, messages could reach speeds of up to 500km/h (Sin Chan, “A brief history…”)! One of the system’s first messages transferred a single signal from Lille, France to Paris (a distance of 230km) in 9 minutes with the full message reaching its destination in 32 minutes (Sin Chan, “A brief history…”). The same message would have taken a horseback rider multiple days.
The Semaphore Telegraph System was simple, but a massive project. The French government built over 534 towers dotting the French landscape (Schofield, “How Napoleon…”). Each tower was located roughly 10–15km from another, barely within eyesight (using a telescope) (Sin Chan, “A brief history…”). On the top of each tower was a tall mast with a cross beam and two arms. Cross beams and arms were moved into different positions to form different signals (Garfinkel and Grunspan 38). A message would originate from one tower where it was encoded (to protect the meaning of the message) and signaled to the next tower via a series of symbols represented using the arms. The next tower will look at the position and repeat, transferring the message to the next tower in the chain (Garfinkel and Grunspan 38).
To keep the messages secure, tower operators did not know the encryptions, they only repeated the signals and were incredibly trained and skilled to achieve accuracy and speed (Schofield, “How Napoleon…”). Supervisors of the system carried codebooks used to encode and decode the message when it was sent and received.
As I mentioned a few weeks ago, military technology has shaped, defined, and enhanced technology, the optical telegraph is no different. The government used them from conception for military advantage and transferred important intel from the battlefield. In 1794, the system was used to transfer news that a small town, Conde, had been successfully captured. Paris sent a reply message of congratulations, both messages were sent and received the same day (Schofield, “How Napoleon…”).
Napoleon understood the significance of the Semaphore immediately. The night he captured Paris, in 1799, he used it to send a short message: “Paris is quiet and the good citizens are content” (Josh, “Chappe Optical…”). He even built a mobile tower unit he could transport into battles. This allowed the system to be used during war and share important information from the front lines.
France perfected the system and even delayed deployment of the electrical telegraph, invented by Samuel Morse, due to the optical telegraph’s success. The optical, line-of-sight, telegraphy, was used until the 1850s, when it was finally replaced by the electrical system (Sin Chan, “A brief history…”). Even when the electrical system was put in place, France used the codes Claude Chappe had invented for many more years before adopting Morse Code.
As robust as the optical telegraph was, it did have its flaws. The system worked only when the tower operators could see the next tower. Of course, this is impossible at night, during bad weather, and if anything blocked the towers. The system could only function on good days while the sun was up. The security of the signals was also at stake, especially when used on the battlefield. If the enemy decoded the signal’s meaning, any military advantage could be lost. The optical telegraph was also expensive, cumbersome, and lengthy to implement. Each tower would be built of stone, not a process that could commence overnight.
As electrical telegraph lines stretched across the French countryside, the military abandoned the system and private businesses made use of it. National lottery numbers were communicated (Sin Chan, “A brief history…”) as well as commodity and stock market trade information (Norman, “The Optical Telegraph…”). Today, only a few of the towers remain. Some of them are tourist stops inviting travelers to revisit forgotten technology. Others are being reclaimed by nature.
Many today may consider the optical telegraph system archaic and ancient. While that might be true, it was the optical telegraph that pioneered the first modern long-range communication system. Claude developed a system and devices to use that system. Compared to the smoke signals and horse riders used before, his system was a quantum leap forward. Governments expanded the system in a matter of years, sending communication further and faster than any known message at the time. Our internet is simply an upgrade, sending numbers (our signals) across cables at blazing speeds.
We must remember that it was systems, inventors, and processes like the optical telegraph that gave us our modern technology. The optical telegraph, or Semaphore System, was the first true long-range communication system used for over 61 years, it was extremely analog, but it is the twelfth major milestone in the history of computing.
More on the Military’s Use of Technology:
More on the History of Computers:
Works Cited
Dilhac, J.M. “THE TELEGRAPH OF CLAUDE CHAPPE -AN OPTICAL TELECOMMUNICATION NETWORK FOR THE XVIIITH CENTURY.” ETHW.org, ethw.org/w/images/1/17/Dilhac.pdf.
The Editors of Encyclopaedia Britannica. “Claude Chappe.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 19 Jan. 2020, www.britannica.com/biography/Claude-Chappe.
“First Amendment.” Legal Information Institute, Legal Information Institute, www.law.cornell.edu/constitution/first_amendment.
Foer, Joshua. “Chappe Optical Telegraph.” Atlas Obscura, Atlas Obscura, 4 Sept. 2009, www.atlasobscura.com/places/chappe-optical-telegraph.
Garfinkel, Simson, and Rachel H. Grunspan. The Computer Book: from the Abacus to Artificial Intelligence, 250 Milestones in the History of Computer Science. Sterling, 2018.
Holman Christian Standard Bible. Broadman & Holman, 2003.
Norman, Jeremy. “The Optical Telegraph: Faster than a Messenger on Horseback.” History of Information, 28 Feb. 2015, www.historyofinformation.com/detail.php?id=429.
Schofield, Hugh. “How Napoleon’s Semaphore Telegraph Changed the World.” BBC News, BBC, 17 June 2013, www.bbc.com/news/magazine-22909590.
Sin Chan, Ai. “A Brief History of Optical Telegraph.” Xoxzo Official Blog: Empowerment, 7 Dec. 2018, blog.xoxzo.com/2018/12/07/history-optical-telegraph/.
“Universal Declaration of Human Rights.” United Nations, United Nations, www.un.org/en/universal-declaration-human-rights/.
