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Ctesibius
Ctesibius or Ktesibios or Tesibius (; BCE) was a Greek inventor and mathematician in Alexandria, Ptolemaic Egypt. Very little is known of Ctesibius' life, but his inventions were well known in his lifetime. He was likely the first head of the Museum of Alexandria. He wrote the first treatises on the science of compressed air and its uses in pumps (and even in a kind of cannon). This, in combination with his work ''On pneumatics'' on the elasticity of air, earned him the title of "father of pneumatics." None of his written work has survived, including his ''Memorabilia,'' a compilation of his research that was cited by Athenaeus. Ctesibius' most commonly known invention today is a pipe organ (hydraulis), a predecessor of the modern church organ. Inventions Ctesibius was the son of a barber, born BCE, probablybut not certainlyin Alexandria. He began his career as a barber, following his father. During this first career, he invented a counterweight-adjustable mirror. Another ...
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Water Clock
A water clock, or clepsydra (; ; ), is a timepiece by which time is measured by the regulated flow of liquid into (inflow type) or out from (outflow type) a vessel, and where the amount of liquid can then be measured. Water clocks are some of the oldest time-measuring instruments. The simplest form of water clock, with a bowl-shaped outflow, existed in Babylon, Egypt, and Persia around the 16th century BC. Other regions of the world, including India and China, also provide early evidence of water clocks, but the earliest dates are less certain. Water clocks were used in ancient Greece and in ancient Rome, as described by technical writers such as Ctesibius (died 222 BC) and Vitruvius (died after 15 BC). Designs A water clock uses the flow of water to measure time. If viscosity is neglected, the physical principle required to study such clocks is Torricelli's law. Two types of water clock exist: inflow and outflow. In an outflow water clock, a container is filled with wate ...
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Hydraulis Organ Of Ctesibius
The water organ or hydraulic organ () (early types are sometimes called hydraulos, hydraulus or hydraula) is a type of pipe organ blown by air, where the power source pushing the air is derived by water from a natural source (e.g. by a waterfall) or by a manual pump. Consequently, the water organ lacks a bellows, blower, or compressor. The hydraulic organ is often confused with the hydraulis. The hydraulis is the name of a Greek instrument created by Ctesibius of Alexandria. The hydraulis has a reservoir of air which is inserted into a cistern of water. The air is pushed into the reservoir with hand pumps, and exits the reservoir as pressurized air to blow through the pipes. The reservoir is open on the bottom, allowing water to maintain the pressure on the air as the air supply fluctuates from either the pumps pushing more air in, or the pipes letting air out. On the water organ, since the 15th century, the water is also used as a source of power to drive a mechanism similar t ...
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De Architectura
(''On architecture'', published as ''Ten Books on Architecture'') is a treatise on architecture written by the Ancient Rome, Roman architect and military engineer Vitruvius, Marcus Vitruvius Pollio and dedicated to his patron, the emperor Caesar Augustus, as a guide for Caesar Augustus#Building projects, building projects. As the only treatise on architecture to survive from antiquity, it has been regarded since the Renaissance as the first known book on architectural theory, as well as a major source on the canon of classical architecture. It contains a variety of information on Greek and Roman buildings, as well as prescriptions for the planning and design of military camps, cities, and structures both large (aqueducts, buildings, baths, harbours) and small (machines, measuring devices, instruments). Since Vitruvius wrote early in the Roman architectural revolution that saw the full development of cross vaulting, domes, Roman concrete, concrete, and other innovations associa ...
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Pneumatics
Pneumatics (from Greek 'wind, breath') is the use of gas or pressurized air in mechanical systems. Pneumatic systems used in industry are commonly powered by compressed air or compressed inert gases. A centrally located and electrically-powered compressor powers cylinders, air motors, pneumatic actuators, and other pneumatic devices. A pneumatic system controlled through manual or automatic solenoid valves is selected when it provides a lower cost, more flexible, or safer alternative to electric motors, and hydraulic actuators. Pneumatics also has applications in dentistry, construction, mining, and other areas. History Although the early history of pneumatics is somewhat unclear, blowguns are often considered the earliest pneumatic device, being created independently by various indigenous groups around the world. Bellows are an early form of air compressor used primarily for smelting and forging. Ctesibius of Alexandria is often considered the father of pneum ...
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Pipe Organ
The pipe organ is a musical instrument that produces sound by driving pressurised air (called ''wind'') through the organ pipes selected from a Musical keyboard, keyboard. Because each pipe produces a single tone and pitch, the pipes are provided in sets called ''ranks'', each of which has a common timbre, volume, and construction throughout the keyboard Compass (music), compass. Most organs have many ranks of pipes of differing pitch, timbre, and volume that the player can employ singly or in combination through the use of controls called Organ stop, stops. A pipe organ has one or more keyboards (called ''Manual (music), manuals'') played by the hands, and most have a Pedal keyboard, pedal clavier played by the feet; each keyboard controls its own division (group of stops). The keyboard(s), pedalboard, and stops are housed in the organ's Organ console, ''console''. The organ's continuous supply of wind allows it to sustain notes for as long as the corresponding keys are pressed, ...
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Vitruvius
Vitruvius ( ; ; –70 BC – after ) was a Roman architect and engineer during the 1st century BC, known for his multi-volume work titled . As the only treatise on architecture to survive from antiquity, it has been regarded since the Renaissance as the first book on architectural theory, as well as a major source on the canon of classical architecture. It is not clear to what extent his contemporaries regarded his book as original or important. He states that all buildings should have three attributes: , , and ("strength", "utility", and "beauty"), principles reflected in much Ancient Roman architecture. His discussion of perfect proportion in architecture and the human body led to the famous Renaissance drawing of the ''Vitruvian Man'' by Leonardo da Vinci. Little is known about Vitruvius' life, but by his own descriptionDe Arch. Book 1, preface. section 2. he served as an artilleryman, the third class of arms in the Roman military offices. He probably served as a senior of ...
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Greeks In Egypt
The Egyptian Greeks, also known as Egyptiotes () or simply Greeks in Egypt (), are the ethnic Greek community from Egypt that has existed from the Hellenistic period until the aftermath of the Egyptian coup d'état of 1952, when most were forced to leave. Antiquity Greeks have been present in Egypt since at least the 7th century BC. Herodotus visited ancient Egypt in the 5th century BC and claimed that the Greeks were one of the first groups of foreigners that ever lived there. Diodorus Siculus claimed that Rhodian Actis, one of the Heliadae, built the city of Heliopolis before the cataclysm; likewise the Athenians built Sais. Siculus reports that all the Greek cities were destroyed during the cataclysm, but the Egyptian cities including Heliopolis and Sais survived. First historical colonies According to Herodotus (ii. 154), King Psammetichus I (664–610 BC) established a garrison of foreign mercenaries at Daphnae, mostly Carians and Ionian Greeks. In 7th century BC, ...
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Silchester
Silchester is a village and civil parish about north of Basingstoke in Hampshire. It is adjacent to the county boundary with Berkshire and about south-west of Reading. Silchester is most notable for the archaeological site and Roman town of Calleva Atrebatum, an Iron Age and later Atrebates Celtic settlement first occupied by the Romans in about AD 45. The site includes what is considered the best-preserved Roman town wall in Great Britain and the remains of what may be one of the earliest Christian churches found in the British Isles. Today, the modern village lies just outside the ancient Roman walls and maintains a rural character, with a small population and local amenities including a village hall, a pub, and access to walking trails on its extensive commons. History Archaeology The University of Reading is leading a five-year archaeological research project to explore the later prehistoric use of the landscape around Silchester Roman Town and its underlying Late Iro ...
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Force Pump
A piston pump is a type of positive displacement pump where the high-pressure seal reciprocates with the piston. Piston pumps can be used to move liquids or compress gases. They can operate over a wide range of pressures. High pressure operation can be achieved without adversely affecting flow rate. Piston pumps can also deal with viscous media and media containing solid particles. This pump type functions through a piston cup, oscillation mechanism where down-strokes cause pressure differentials, filling of pump chambers, where up-stroke forces the pump fluid out for use. Piston pumps are often used in scenarios requiring high, consistent pressure and in water irrigation or delivery systems. Types The two main types of piston pump are the lift pump and the force pump. Both types may be operated either by hand or by an engine. Lift pump In a lift pump, the upstroke of the piston draws water, through a valve, into the lower part of the cylinder. On the downstroke, water passes th ...
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Pendulum Clock
A pendulum clock is a clock that uses a pendulum, a swinging weight, as its timekeeping element. The advantage of a pendulum for timekeeping is that it is an approximate harmonic oscillator: It swings back and forth in a precise time interval dependent on its length, and resists swinging at other rates. From its invention in 1656 by Christiaan Huygens, inspired by Galileo Galilei, until the 1930s, the pendulum clock was the world's most precise timekeeper, accounting for its widespread use. Throughout the 18th and 19th centuries, pendulum clocks in homes, factories, offices, and railroad stations served as primary time standards for scheduling daily life, work shifts, and public transportation. Their greater accuracy allowed for the faster pace of life which was necessary for the Industrial Revolution. The home pendulum clock was replaced by less-expensive synchronous electric clocks in the 1930s and 1940s. Pendulum clocks are now kept mostly for their Interior decor, decorative ...
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