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Hydraulic Telegraph
A hydraulic telegraph ( el, υδραυλικός τηλέγραφος) refers to two different semaphore systems involving the use of water-based mechanisms as a telegraph. The earliest one was developed in 4th-century BC Greece, while the other was developed in 19th-century AD Britain. The Greek system was deployed in combination with semaphoric fires, while the latter British system was operated purely by hydraulic fluid pressure. Although both systems employed water in their sending and receiver devices, their transmission media were completely different. The ancient Greek system transmitted its semaphoric information to the receiver visually, which limited its use to line-of-sight distances in good visibility weather conditions only. The 19th-century British system used water-filled pipes to effect changes to the water level in the receiver unit (similar to a transparent water-filled flexible tube used as a level indicator), thus limiting its range to the hydraulic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Hydraulic Telegraph Of Aeneas Relief
Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor of all known varieties of Greek. **Mycenaean Greek, most ancient attested form of the language (16th to 11th centuries BC). **Ancient Greek, forms of the language used c. 1000–330 BC. **Koine Greek, common form of Greek spoken and written during Classical antiquity. **Medieval Greek or Byzantine Language, language used between the Middle Ages and the Ottoman conquest of Constantinople. **Modern Greek, varieties spoken in the modern era (from 1453 AD). *Greek alphabet, script used to write the Greek language. *Greek Orthodox Church, several Churches of the Eastern Orthodox Church. *Ancient Greece, the ancient civilization before the end of Antiquity. *Old Greek, the language as spoken from Late Antiquity to around 1500 AD. Other uses * '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Histories (Polybius)
Polybius’ ''Histories'' ( grc-gre, Ἱστορίαι ''Historíai'') were originally written in 40 volumes, only the first five of which are extant in their entirety. The bulk of the work was passed down through collections of excerpts kept in libraries in the Byzantine Empire. Polybius, a historian from the Greek city of Megalopolis in Arcadia, was taken as a hostage to Rome after the Roman victory in the Third Macedonian War (171–168 BC), and there he began to write an account of the rise of Rome to a great power. Content Polybius' ''Histories'' begin in the year 264 BC and end in 146 BC (Polybius was born around 200 BC and died around 117 BC). He is primarily concerned with the 53 years in which Ancient Rome became a dominant world power. This period, from 220–167 BC, saw Rome subjugate Carthage and gain control over Hellenistic Greece. Books I through V cover the affairs of important states at the time (Ptolemaic Egypt, Hellenistic Greece, Macedon) and deal extensiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek Military Equipment
Ancient history is a time period from the beginning of writing and recorded human history to as far as late antiquity. The span of recorded history is roughly 5,000 years, beginning with the Sumerian cuneiform script. Ancient history covers all continents inhabited by humans in the period 3000 BCAD 500. The three-age system periodizes ancient history into the Stone Age, the Bronze Age, and the Iron Age, with recorded history generally considered to begin with the Bronze Age. The start and end of the three ages varies between world regions. In many regions the Bronze Age is generally considered to begin a few centuries prior to 3000 BC, while the end of the Iron Age varies from the early first millennium BC in some regions to the late first millennium AD in others. During the time period of ancient history, the world population was already exponentially increasing due to the Neolithic Revolution, which was in full progress. While in 10,000 BC, the world population stood at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek Military Terminology
Ancient history is a time period from the beginning of writing and recorded human history to as far as late antiquity. The span of recorded history is roughly 5,000 years, beginning with the Sumerian cuneiform script. Ancient history covers all continents inhabited by humans in the period 3000 BCAD 500. The three-age system periodizes ancient history into the Stone Age, the Bronze Age, and the Iron Age, with recorded history generally considered to begin with the Bronze Age. The start and end of the three ages varies between world regions. In many regions the Bronze Age is generally considered to begin a few centuries prior to 3000 BC, while the end of the Iron Age varies from the early first millennium BC in some regions to the late first millennium AD in others. During the time period of ancient history, the world population was already exponentially increasing due to the Neolithic Revolution, which was in full progress. While in 10,000 BC, the world population stood at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek Technology
Ancient Greek technology developed during the 5th century BC, continuing up to and including the Roman period, and beyond. Inventions that are credited to the ancient Greeks include the gear, screw, rotary mills, bronze casting techniques, water clock, water organ, the torsion catapult, the use of steam to operate some experimental machines and toys, and a chart to find prime numbers. Many of these inventions occurred late in the Greek period, often inspired by the need to improve weapons and tactics in war. However, peaceful uses are shown by their early development of the watermill, a device which pointed to further exploitation on a large scale under the Romans. They developed surveying and mathematics to an advanced state, and many of their technical advances were published by philosophers, like Archimedes and Heron. Water technology Some fields that were encompassed in the area of water resources (mainly for urban use) included groundwater exploitation, construction of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Communications
Optical communication, also known as optical telecommunication, is communication at a distance using light to carry information. It can be performed visually or by using electronic devices. The earliest basic forms of optical communication date back several millennia, while the earliest electrical device created to do so was the photophone, invented in 1880. An optical communication system uses a transmitter, which encodes a message into an optical signal, a channel, which carries the signal to its destination, and a receiver, which reproduces the message from the received optical signal. When electronic equipment is not employed the 'receiver' is a person visually observing and interpreting a signal, which may be either simple (such as the presence of a beacon fire) or complex (such as lights using color codes or flashed in a Morse code sequence). Modern communication relies on optical networking systems using optical fiber, optical amplifiers, lasers, switches, routers, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telegraphy
Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas pigeon post is not. Ancient signalling systems, although sometimes quite extensive and sophisticated as in China, were generally not capable of transmitting arbitrary text messages. Possible messages were fixed and predetermined and such systems are thus not true telegraphs. The earliest true telegraph put into widespread use was the optical telegraph of Claude Chappe, invented in the late 18th century. The system was used extensively in France, and European nations occupied by France, during the Napoleonic era. The electric telegraph started to replace the optical telegraph in the mid-19th century. It was first taken up in Britain in the form of the Cooke and Wheatstone telegraph, initially used mostly as an aid to railway signalling. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Telecommunications
The history of telecommunication began with the use of smoke signals and drum (communication), drums in Africa, Asia, and the Americas. In the 1790s, the first fixed semaphore line, semaphore systems emerged in Europe. However, it was not until the 1830s that electrical telecommunication systems started to appear. This article details the history of telecommunication and the individuals who helped make telecommunication systems what they are today. The history of telecommunication is an important part of the larger history of communication. Ancient systems and optical telegraphy Early telecommunications included smoke signals and drum (communication), drums. Talking drums were used by natives in Africa, and smoke signals in North America and China. These systems were often used to do more than announce the presence of a military camp. In Azazel#Rabbinical_Judaism, Rabbinical Judaism a signal was given by means of kerchiefs or flags at intervals along the way back to the high p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal Lamp
Signal lamp training during World War II A signal lamp (sometimes called an Aldis lamp or a Morse lamp) is a semaphore system using a visual signaling device for optical communication, typically using Morse code. The idea of flashing dots and dashes from a lantern was first put into practice by Captain Philip Howard Colomb, of the Royal Navy, in 1867. Colomb's design used limelight for illumination, and his original code was not the same as Morse code. During World War I, German signalers used optical Morse transmitters called ', with a range of up to 8 km (5 miles) at night, using red filters for undetected communications. Modern signal lamps produce a focused pulse of light, either by opening and closing shutters mounted in front of the lamp, or by tilting a concave mirror. They continue to be used to the present day on naval vessels and for aviation light signals in air traffic control towers, as a backup device in case of a complete failure of an aircraft's radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Communication
Optical communication, also known as optical telecommunication, is communication at a distance using light to carry information. It can be performed visually or by using electronic devices. The earliest basic forms of optical communication date back several millennia, while the earliest electrical device created to do so was the photophone, invented in 1880. An optical communication system uses a transmitter, which encodes a message into an optical signal, a channel, which carries the signal to its destination, and a receiver, which reproduces the message from the received optical signal. When electronic equipment is not employed the 'receiver' is a person visually observing and interpreting a signal, which may be either simple (such as the presence of a beacon fire) or complex (such as lights using color codes or flashed in a Morse code sequence). Modern communication relies on optical networking systems using optical fiber, optical amplifiers, lasers, switches, routers, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliograph
A heliograph () is a semaphore system that signals by flashes of sunlight (generally using Morse code) 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, survey and forest protection work. Heliographs were standard issue in the British and Australian armies until the 1960s, and were used by the Pakistani army as late as 1975. Description There were many heliograph types. Most heliographs were variants of the British Army Mance Mark V version (Fig.1). 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 then adj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fryctoria
Phryctoria ( el, φρυκτωρία) was a semaphore system used in Ancient Greece. The ''phryctoriae'' were towers built on selected mountaintops so that one tower (''phryctoria'') would be visible to the next tower (usually 20 miles away). The towers were used for the transmission of a specific prearranged message. Flames were lit on one tower and then the next tower in succession also lit flames. In Aeschylus tragedy ''Agamemnon'', a slave watchman character learns the news of Troy's fall from Mycenae by carefully watching a fire beacon. Thucydides wrote that during the Peloponnesian War, the Peloponnesians who were in Corcyra were informed by night-time beacon signals of the approach of sixty Athenian vessels from Lefkada. Phryctoriae and Pyrseia Ιn the 2nd century BC, the Greek engineers from Alexandria, Cleoxenes ( el, Κλεόξενος) and Democletus ( el, Δημόκλειτος) invented the pyrseia ( el, πυρσεία). Πυρσεία from πυρσός which means t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
