Table Bay
Table Bay is a natural bay on the Atlantic Ocean overlooked by Cape Town and is at the northern end of the Cape Peninsula, which stretches south to the Cape of Good Hope. It was named. Bartolomeu Dias was the first European to explore this region in 1486; the bay, although famous for centuries as a haven for ships, is a rather poor natural harbour and is badly exposed to gales from both the SE and NW. Many sailing ships seeking refuge in the bay during the 17th and 18th centuries were driven ashore by storms; the Dutch colonists persisted with their efforts on the shores of Table Bay, because good natural harbours along this coastline are non-existent. The best of them- Saldanha Bay- lacked fresh water and the only realistic alternatives- Simon's Bay and Houtbaai- were rightly inaccessible at the time and only marginally less exposed to the weather, notoriously bad enough in the Cape Peninisula. A harbour was built in Table Bay by a process of land reclamation and was defended by breakwaters to protect shipping.
The older part of this structure is called the Victoria Dock. The newer part is called the Duncan Dock. Robben Island, where Nelson Mandela was imprisoned for decades, is in this bay. False Bay Eduard Bohlen
Aboriginal Australians
Aboriginal Australian is a collective term for all the indigenous peoples from the Australian mainland and Tasmania. This group contains many separate cultures that have developed in the various environments of Australia for more than 50,000 years; these peoples have a broadly shared, though complex, genetic history, but it is only in the last two hundred years that they have been defined and started to self identify as a single group. The exact definition of the term Aboriginal Australian has changed over time and place, with the importance of family lineage, self identification and community acceptance all being of varying importance. In the past Aboriginal Australians lived over large sections of the continental shelf and were isolated on many of the smaller offshore islands, once the land was inundated at the start of the inter-glacial. However, they are distinct from the Torres Strait Islander people, despite extensive cultural exchange. Today Aboriginal Australians comprise 3.1% of Australia's population.
They live throughout the world as part of the Australia diaspora. Before extensive European settlement, there were over 200 Aboriginal languages. However, today most Aboriginal people speak English, with Aboriginal phrases and words being added to create Australian Aboriginal English, they have a number of health and economic deprivations in comparison with the wider Australian community. A new definition was proposed in the Constitutional Section of the Department of Aboriginal Affairs' Report on a Review of the Administration of the Working Definition of Aboriginal and Torres Strait Islanders: An Aboriginal or Torres Strait Islander is a person of Aboriginal or Torres Strait Islander descent who identifies as an Aboriginal or Torres Strait Islander and is accepted as such by the community in which he lives. Justice Gerard Brennan in his leading judgment in Mabo v Queensland stated: Membership of the Indigenous people depends on biological descent from the Indigenous people and on mutual recognition of a particular person's membership by that person and by the elders or other persons enjoying traditional authority among those people.
The category "Aboriginal Australia" was coined by the British after they began colonising Australia in 1788, to refer collectively to all people they found inhabiting the continent, to the descendants of any of those people. Until the 1980s, the sole legal and administrative criterion for inclusion in this category was race, classified according to visible physical characteristics or known ancestors; as in the British slave colonies of North America and the Caribbean, where the principle of partus sequitur ventrem was adopted from 1662, children's status was determined by that of their mothers: if born to Aboriginal mothers, children were considered Aboriginal, regardless of their paternity. In the era of colonial and post-colonial government, access to basic human rights depended upon your race. If you were a "full-blooded Aboriginal native... any person having an admixture of Aboriginal blood", a half-caste being the "offspring of an Aboriginal mother and other than Aboriginal father", a "quadroon", or had a "strain" of Aboriginal blood you were forced to live on Reserves or Missions, work for rations, given minimal education, needed governmental approval to marry, visit relatives or use electrical appliances.
The Constitution of Australia, in its original form as of 1901, referred to Aboriginals twice, but without definition. Section 51 gave the Commonwealth parliament a power to legislate with respect to "the people of any race" throughout the Commonwealth, except for people of "the aboriginal race"; the purpose of this provision was to give the Commonwealth power to regulate non-white immigrant workers, who would follow work opportunities interstate. The only other reference, Section 127, provided that "aboriginal natives shall not be counted" in reckoning the size of the population of the Commonwealth or any part of it; the purpose of Section 127 was to prevent the inclusion of Aboriginal people in Section 24 determinations of the distribution of House of Representatives seats amongst the states and territories. After these references were removed by the 1967 referendum, the Australian Constitution had no references to Aboriginals. Since that time, there have been a number of proposals to amend the constitution to mention Indigenous Australians.
The change to Section 51 enabled the Commonwealth parliament to enact laws with respect to Aboriginal peoples as a "race". In the Tasmanian Dam Case of 1983, the High Court of Australia was asked to determine whether Commonwealth legislation, whose application could relate to Aboriginal people—parts of the World Heritage Properties Conservation Act 1983 as well as related legislation—was supported by Section 51 in its new form; the case concerned an application of legislation that would preserve the cultural heritage of Aboriginal Tasmanians. It was held that Aboriginal Australians and Torres Strait Islanders, together or separately, any part of either, could be regarded as a "race" for this purpose; as to the criteria for identifying a person as a member of such a "race", the definition by Justice Deane has become accepted as current law. Deane said: It is unnecessary, for the purposes of the present case, to consider the meaning to be given to the phrase "people of any race" in s. 51. Plainly, the words have a wide and non-technical meaning....
The phrase is, in my view, apposite to refer to all Australian Aboriginals collectively. Any doubt, which might otherwise exist in that regard, is removed
History of radio
The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed. Radio development began as "wireless telegraphy". Radio history involves matters of broadcasting; the idea of wireless communication predates the discovery of "radio" with experiments in "wireless telegraphy" via inductive and capacitive induction and transmission through the ground and train tracks from the 1830s on. James Clerk Maxwell showed in theoretical and mathematical form in 1864 that electromagnetic waves could propagate through free space, it is that the first intentional transmission of a signal by means of electromagnetic waves was performed in an experiment by David Edward Hughes around 1880, although this was considered to be induction at the time. In 1888 Heinrich Rudolf Hertz was able to conclusively prove transmitted airborne electromagnetic waves in an experiment confirming Maxwell's theory of electromagnetism.
After the discovery of these "Hertzian waves" many scientists and inventors experimented with wireless transmission, some trying to develop a system of communication, some intentionally using these new Hertzian waves, some not. Maxwell's theory showing that light and Hertzian electromagnetic waves were the same phenomenon at different wavelengths led "Maxwellian" scientist such as John Perry, Frederick Thomas Trouton and Alexander Trotter to assume they would be analogous to optical signaling and the Serbian American engineer Nikola Tesla to consider them useless for communication since "light" could not transmit further than line of sight. In 1892 the physicist William Crookes wrote on the possibilities of wireless telegraphy based on Hertzian waves and in 1893 Tesla proposed a system for transmitting intelligence and wireless power using the earth as the medium. Others, such as Amos Dolbear, Sir Oliver Lodge, Reginald Fessenden, Alexander Popov were involved in the development of components and theory involved with the transmission and reception of airborne electromagnetic waves for their own theoretical work or as a potential means of communication.
Over several years starting in 1894 the Italian inventor Guglielmo Marconi built the first complete, commercially successful wireless telegraphy system based on airborne Hertzian waves. Marconi demonstrated the application of radio in military and marine communications and started a company for the development and propagation of radio communication services and equipment; the meaning and usage of the word "radio" has developed in parallel with developments within the field of communications and can be seen to have three distinct phases: electromagnetic waves and experimentation. In an 1864 presentation, published in 1865, James Clerk Maxwell proposed theories of electromagnetism, with mathematical proofs, that showed that light and predicted that radio and x-rays were all types of electromagnetic waves propagating through free space. In 1886–88 Heinrich Rudolf Hertz conducted a series of experiments that proved the existence of Maxwell's electromagnetic waves, using a frequency in what would be called the radio spectrum.
Many individuals—inventors, engineers and businessmen—constructed systems based on their own understanding of these and other phenomena, some predating Maxwell and Hertz's discoveries. Thus "wireless telegraphy" and radio wave-based systems can be attributed to multiple "inventors". Development from a laboratory demonstration to a commercial entity spanned several decades and required the efforts of many practitioners. In 1878, David E. Hughes noticed that sparks could be heard in a telephone receiver when experimenting with his carbon microphone, he developed this carbon-based detector further and could detect signals over a few hundred yards. He demonstrated his discovery to the Royal Society in 1880, but was told it was induction, therefore abandoned further research. Thomas Edison came across the electromagnetic phenomenon while experimenting with a telegraph at Menlo Park, he noted an unexplained transmission effect while experimenting with a telegraph. He referred to this as etheric force in an announcement on November 28, 1875.
Elihu Thomson published his findings on Edison's new "force", again attributing it to induction, an explanation that Edison accepted. Edison would go on the next year to take out U. S. Patent 465,971 on a system of electrical wireless communication between ships based on electrostatic coupling using the water and elevated terminals. Although this was not a radio system, Edison would sell his patent rights to his friend Guglielmo Marconi at the Marconi Company in 1903, rather than another interested party who might end up working against Marconi's interests. Between 1886 and 1888 Heinrich Rudolf Hertz published the results of his experiments wherein he was able to transmit electromagnetic waves through the air, proving Maxwell's electromagnetic theory. Thus, given Hertz comprehensive discoveries, radio waves were referred to as "Hertzian waves". Between 1890 and 1892 physicists such as John Perry, Frederick Thomas Trouton and William Crookes proposed electromagnetic or Hertzian waves as a navigation aid or means of communication, with Crookes writing on the possibilities of wireless telegraphy based on Hertzian waves in 1892.
After learning of Hertz' demonstrations of wireless transmission, inventor Nikola Tesla began developing his own systems based on Hertz' and Maxwell's ideas working toward a means o
Indigenous peoples of the Americas
The indigenous peoples of the Americas are the Pre-Columbian peoples of North and South America and their descendants. Although some indigenous peoples of the Americas were traditionally hunter-gatherers—and many in the Amazon basin, still are—many groups practiced aquaculture and agriculture; the impact of their agricultural endowment to the world is a testament to their time and work in reshaping and cultivating the flora indigenous to the Americas. Although some societies depended on agriculture, others practiced a mix of farming and gathering. In some regions the indigenous peoples created monumental architecture, large-scale organized cities, city-states, states and empires. Among these are the Aztec and Maya states that until the 16th century were among the most politically and advanced nations in the world, they had a vast knowledge of engineering, mathematics, writing, medicine and irrigation, mining and goldsmithing. Many parts of the Americas are still populated by indigenous peoples.
At least a thousand different indigenous languages are spoken in the Americas. Some, such as the Quechuan languages, Guaraní, Mayan languages and Nahuatl, count their speakers in millions. Many maintain aspects of indigenous cultural practices to varying degrees, including religion, social organization and subsistence practices. Like most cultures, over time, cultures specific to many indigenous peoples have evolved to incorporate traditional aspects but cater to modern needs; some indigenous peoples still live in relative isolation from Western culture and a few are still counted as uncontacted peoples. Indigenous peoples of the United States are known as Native Americans or American Indians and Alaska Natives. Application of the term "Indian" originated with Christopher Columbus, who, in his search for India, thought that he had arrived in the East Indies; those islands came to be known as the "West Indies", a name still used. This led to the blanket term "Indies" and "Indians" for the indigenous inhabitants, which implied some kind of racial or cultural unity among the indigenous peoples of the Americas.
This unifying concept, codified in law and politics, was not accepted by the myriad groups of indigenous peoples themselves, but has since been embraced or tolerated, by many over the last two centuries. Though the term "Indian" does not include the culturally and linguistically distinct indigenous peoples of the Arctic regions of the Americas—such as the Aleuts, Inuit or Yupik peoples, who entered the continent as a second more recent wave of migration several thousand years before and have much more recent genetic and cultural commonalities with the aboriginal peoples of the Asiatic Arctic Russian Far East—these groups are nonetheless considered "indigenous peoples of the Americas". Indigenous peoples are known in Canada as Aboriginal peoples, which includes not only First Nations and Arctic Inuit, but the minority population of First Nations-European mixed race Métis people who identify culturally and ethnically with indigenous peoplehood; this is contrasted, for instance, to the American Indian-European mixed race mestizos of Hispanic America who, with their larger population, identify as a new ethnic group distinct from both Europeans and Indigenous Americans, but still considering themselves a subset of the European-derived Hispanic or Brazilian peoplehood in culture and ethnicity.
The term Amerindian and its cognates find preferred use in scientific contexts and in Quebec, the Guianas and the English-speaking Caribbean. Indígenas or pueblos indígenas is a common term in Spanish-speaking countries and pueblos nativos or nativos may be heard, while aborigen is used in Argentina and pueblos originarios is common in Chile. In Brazil, indígenas or povos indígenas are common if formal-sounding designations, while índio is still the more often-heard term and aborígene and nativo being used in Amerindian-specific contexts; the Spanish and Portuguese equivalents to Indian could be used to mean any hunter-gatherer or full-blooded Indigenous person to continents other than Europe or Africa—for example, indios filipinos. The specifics of Paleo-Indian migration to and throughout the Americas, including the exact dates and routes traveled, are the subject of ongoing research and discussion. According to archaeological and genetic evidence and South America were the last continents in the world to gain human habitation.
During the Wisconsin glaciation, 50–17,000 years ago, falling sea levels allowed people to move across the land bridge of Beringia that joined Siberia to northwest North America. Alaska was a glacial refugium; the Laurentide Ice Sheet covered most of North America, blocking nomadic inhabitants and confining them to Alaska for thousands of years. Indigenous genetic studies suggest that the first inhabitants of the Americas share a single ancestral population, one that developed in isolation, conjectured to be Beringia; the isolat
History of China
The earliest known written records of the history of China date from as early as 1250 BC, from the Shang dynasty, during the king Wu Ding's reign, recorded as the twenty-first Shang king by the written records of Shang dynasty unearthed. Ancient historical texts such as the Records of the Grand Historian and the Bamboo Annals describe a Xia dynasty before the Shang, but no writing is known from the period, Shang writings do not indicate the existence of the Xia; the Shang ruled in the Yellow River valley, held to be the cradle of Chinese civilization. However, Neolithic civilizations originated at various cultural centers along both the Yellow River and Yangtze River; these Yellow River and Yangtze civilizations arose millennia before the Shang. With thousands of years of continuous history, China is one of the world's oldest civilizations, is regarded as one of the cradles of civilization; the Zhou dynasty supplanted the Shang, introduced the concept of the Mandate of Heaven to justify their rule.
The central Zhou government began to weaken due to external and internal pressures in the 8th century BC, the country splintered into smaller states during the Spring and Autumn period. These states became warred with one another in the following Warring States period. Much of traditional Chinese culture and philosophy first developed during those troubled times. In 221 BC, Qin Shi Huang conquered the various warring states and created for himself the title of Huangdi or "emperor" of the Qin, marking the beginning of imperial China. However, the oppressive government fell soon after his death, was supplanted by the longer-lived Han dynasty. Successive dynasties developed bureaucratic systems that enabled the emperor to control vast territories directly. In the 21 centuries from 206 BC until AD 1912, routine administrative tasks were handled by a special elite of scholar-officials. Young men, well-versed in calligraphy, history and philosophy, were selected through difficult government examinations.
China's last dynasty was the Qing, replaced by the Republic of China in 1912, in the mainland by the People's Republic of China in 1949, resulting in two de facto states claiming to be the legitimate government of all China. Chinese history has alternated between periods of political unity and peace, periods of war and failed statehood – the most recent being the Chinese Civil War. China was dominated by steppe peoples, most of whom were assimilated into the Han Chinese culture and population. Between eras of multiple kingdoms and warlordism, Chinese dynasties have ruled parts or all of China. Traditional culture, influences from other parts of Asia and the Western world, form the basis of the modern culture of China. What is now China was inhabited by Homo erectus more than a million years ago. Recent study shows that the stone tools found at Xiaochangliang site are magnetostratigraphically dated to 1.36 million years ago. The archaeological site of Xihoudu in Shanxi Province has evidence of use of fire by Homo erectus, dated 1.27 million years ago, Homo erectus fossils in China include the Yuanmou Man, the Lantian Man and the Peking Man.
Fossilised teeth of Homo sapiens dating to 125,000–80,000 BC have been discovered in Fuyan Cave in Dao County in Hunan. Evidence of Middle Palaeolithic Levallois technology has been found in the lithic assemblage of Guanyindong Cave site in southwest China, dated to 170,000–80,000 years ago; the Neolithic age in China can be traced back to about 10,000 BC. The earliest evidence of cultivated rice, found by the Yangtze River, is carbon-dated to 8,000 years ago. Early evidence for proto-Chinese millet agriculture is radiocarbon-dated to about 7000 BC. Farming gave rise to the Jiahu culture. At Damaidi in Ningxia, 3,172 cliff carvings dating to 6000–5000 BC have been discovered, "featuring 8,453 individual characters such as the sun, stars and scenes of hunting or grazing"; these pictographs are reputed to be similar to the earliest characters confirmed to be written Chinese. Chinese proto-writing existed in Jiahu around 7000 BC, Dadiwan from 5800 BC to 5400 BC, Damaidi around 6000 BC and Banpo dating from the 5th millennium BC.
Some scholars have suggested. Excavation of a Peiligang culture site in Xinzheng county, found a community that flourished in 5,500 to 4,900 BC, with evidence of agriculture, constructed buildings and burial of the dead. With agriculture came increased population, the ability to store and redistribute crops, the potential to support specialist craftsmen and administrators. In late Neolithic times, the Yellow River valley began to establish itself as a center of Yangshao culture, the first villages were founded. Yangshao culture was superseded by the Longshan culture, centered on the Yellow River from about 3000 BC to 2000 BC. Bronze artifacts have been found at the Majiayao culture site, The Bronze Age is represented at the Lower Xiajiadian culture site in northeast China. Sanxingdui located in what is now Sichuan province is believed to be the site of a major ancient city, of a unknown Bronze Age culture; the site was first discovered in 1929 and re-dis
Heliograph
A heliograph is a wireless telegraph that signals by flashes of sunlight reflected by a mirror. The flashes are produced by momentarily pivoting the mirror, or by interrupting the beam with a shutter; the heliograph was a simple but effective instrument for instantaneous optical communication over long distances during the late 19th and early 20th century. Its main uses were military and forest protection work. Heliographs were standard issue in the British and Australian armies until the 1960s, were used by the Pakistani army as late as 1975. There were many heliograph types. Most heliographs were variants of the British Army Mance Mark V version, it used a mirror with a small unsilvered spot in the centre. The sender aligned the heliograph to the target by looking at the reflected target in the mirror and moving their head until the target was hidden by the unsilvered spot. Keeping their head still, they adjusted the aiming rod so its cross wires bisected the target, they turned up the sighting vane, which covered the cross wires with a diagram of a cross, aligned the mirror with the tangent and elevation screws so the small shadow, the reflection of the unsilvered spot hole was on the cross target.
This indicated. The flashes were produced by a keying mechanism that tilted the mirror up a few degrees at the push of a lever at the back of the instrument. If the sun was in front of the sender, its rays were reflected directly from this mirror to the receiving station. If the sun was behind the sender, the sighting rod was replaced by a second mirror, to capture the sunlight from the main mirror and reflect it to the receiving station; the U. S. Signal Corps heliograph mirror did not tilt; this type produced flashes by a shutter mounted on a second tripod. The heliograph had some great advantages, it allowed long distance communication without a fixed infrastructure, though it could be linked to make a fixed network extending for hundreds of miles, as in the fort-to-fort network used for the Geronimo campaign. It was portable, did not require any power source, was secure since it was invisible to those not near the axis of operation, the beam was narrow, spreading only 50 feet per mile of range.
However, anyone in the beam with the correct knowledge could intercept signals without being detected. In the Boer War, where both sides used heliographs, tubes were sometimes used to decrease the dispersion of the beam. In some other circumstances, though, a narrow beam made it difficult to stay aligned with a moving target, as when communicating from shore to a moving ship, so the British issued a dispersing lens to broaden the heliograph beam from its natural diameter of 0.5 degrees to 15 degrees. The distance that heliograph signals could be seen depended on the clarity of the sky and the size of the mirrors used. A clear line of sight was required, since the Earth's surface is curved, the highest convenient points were used. Under ordinary conditions, a flash could be seen 30 miles with the naked eye, much farther with a telescope; the maximum range was considered to be 10 miles for each inch of mirror diameter. Mirrors ranged from 1.5 inches to 12 inches or more. The record distance was established by a detachment of U.
S. signal sergeants by the inter-operation of stations on Mount Ellen and Mount Uncompahgre, Colorado, 183 miles apart on September 17, 1894, with Signal Corps heliographs carrying mirrors only 8 inches square. The German professor Carl Friedrich Gauss of the University of Göttingen developed and used a predecessor of the heliograph in 1821, his device directed a controlled beam of sunlight to a distant station to be used as a marker for geodetic survey work, was suggested as a means of telegraphic communications. This is the first reliably documented heliographic device, despite much speculation about possible ancient incidents of sun-flash signalling, the documented existence of other forms of ancient optical telegraphy. For example, one author in 1919 chose to "hazard the theory" that the mainland signals Roman emperor Tiberius watched for from Capri were mirror flashes, but admitted "there are no references in ancient writings to the use of signaling by mirrors", that the documented means of ancient long-range visual telecommunications was by beacon fires and beacon smoke, not mirrors.
The story that a shield was used as a heliograph at the Battle of Marathon is a modern myth, originating in the 1800s. Herodotus never mentioned any flash. What Herodotus did write was that someone was accused of having arranged to "hold up a shield as a signal". Suspicion grew in the 1900s; the conclusion after testing the theory was "Nobody flashed a shield at the Battle of Marathon". In a letter dated 3 June 1778, John Norris, High Sheriff of Buckinghamshire, notes: "Did this day heliograph intelligence from Dr Franklin in Paris to Wycombe". However, there is little evidence that "heliograph" here is other than a misspelling of "holograph"; the term "heliograph" for solar telegraphy did not enter the English language until the 1870s—even the word "telegraphy" was not coined until the 1790s. Henry Christopher Mance, of the British Government Persian Gulf Telegraph Department, developed the first accepted heliograph about 1869 while stationed at Karachi, in the Bombay Presidency in British India.
Mance was familiar with heliotropes by their use for the Great India Survey. The Mance Heliograph was operated by one man, since it weighed about seven pounds, the operator could carry the devi
Semaphore telegraph
A semaphore telegraph is an early system of conveying information by means of visual signals, using towers with pivoting shutters known as blades or paddles. Information is encoded by the position of the mechanical elements; the most used system was invented in 1792 in France by Claude Chappe, was popular in the late eighteenth to early nineteenth centuries. Lines of relay towers with a semaphore rig at the top were built within line-of-sight of each other, at separations of 5–20 miles. Operators at each tower would watch the neighboring tower through a spyglass, when the semaphore arms began to move spelling out a message, they would pass the message on to the next tower; this system was much faster than post riders for conveying a message over long distances, had cheaper long-term operating costs, once constructed. Semaphore lines were a precursor of the electrical telegraph, which would replace them half a century and would be cheaper and more private; the line-of-sight distance between relay stations was limited by geography and weather, prevented the optical telegraph from crossing wide expanses of water, unless a convenient island could be used for a relay station.
Modern derivatives of the semaphore system include the heliograph. The word semaphore was coined in 1801 by the French inventor of the semaphore line itself, Claude Chappe, he composed it from the Greek elements σῆμα. Chappe coined the word tachygraph, meaning "fast writer". However, the French Army preferred to call Chappe's semaphore system the telegraph, meaning "far writer", coined by French statesman André François Miot de Mélito; the word semaphoric was first printed in English in 1808: "The newly constructed Semaphoric telegraphs", referring to the destruction of telegraphs in France. The word semaphore was first printed in English in 1816: "The improved Semaphore has been erected on the top of the Admiralty", referring to the installation of a simpler telegraph invented by Sir Home Popham. Semaphore telegraphs are called "optical telegraphs", "shutter telegraph chains", "Chappe telegraphs" or "Napoleonic semaphore". Optical telegraphy dates from ancient times, in the form of hydraulic telegraphs and smoke signals.
Modern design of semaphores was first foreseen by the British polymath Robert Hooke, who gave a vivid and comprehensive outline of visual telegraphy to the Royal Society in a 1684 submission in which he outlined many practical details. The system was never put into practice. One of the first experiments of optical signalling was carried out by the Anglo-Irish landowner and inventor, Sir Richard Lovell Edgeworth in 1767, he placed a bet with his friend, the horse racing gambler Lord March, that he could transmit knowledge of the outcome of the race in just one hour. Using a network of signalling sections erected on high ground, the signal would be observed from one station to the next by means of a telescope; the signal itself consisted of a large pointer that could be placed into eight possible positions in 45 degree increments. A series of two such signals gave a total 64 code elements and a third signal took it up to 512, he returned to his idea after hearing of Chappe's system. Credit for the first successful optical telegraph goes to the French engineer Claude Chappe and his brothers in 1792, who succeeded in covering France with a network of 556 stations stretching a total distance of 4,800 kilometres.
Le système Chappe was used for national communications until the 1850s. During 1790–1795, at the height of the French Revolution, France needed a swift and reliable communication system to thwart the war efforts of its enemies. France was surrounded by the forces of Britain, the Netherlands, Prussia and Spain, the cities of Marseille and Lyon were in revolt, the British Fleet held Toulon; the only advantage France held was the lack of cooperation between the allied forces due to their inadequate lines of communication. In the summer of 1790, the Chappe brothers set about devising a system of communication that would allow the central government to receive intelligence and to transmit orders in the shortest possible time. On 2 March 1791 at 11am, they sent the message “si vous réussissez, vous serez bientôt couverts de gloire” between Brulon and Parce, a distance of 16 kilometres; the first means used a combination of black and white panels, clocks and codebooks to send their message. The Chappes carried out experiments during the next two years, on two occasions their apparatus at Place de l'Étoile, Paris was destroyed by mobs who thought they were communicating with royalist forces.
However, in the summer of 1792 Claude was appointed Ingénieur-Télégraphiste and charged with establishing a line of stations between Paris and Lille, a distance of 230 kilometres. It was used to carry dispatches for the war between Austria. In 1794, it brought news of a French capture of Condé-sur-l'Escaut from the Austrians less than an hour after it occurred; the first symbol of a message to Lille would pass through 15 stations in only nine minutes. The speed of the line varied with the weather, but the line to Lille transferred 36 symbols, a complete message, in about 32 minutes. Another line of 50 stations was completed in 1798, covering 488 km betwe
