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Ctesibius Crater AS16-M-0079
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandria
Alexandria ( ; ) is the List of cities and towns in Egypt#Largest cities, second largest city in Egypt and the List of coastal settlements of the Mediterranean Sea, largest city on the Mediterranean coast. It lies at the western edge of the Nile Delta, Nile River delta. Founded in 331 BC by Alexander the Great, Alexandria grew rapidly and became a major centre of Hellenic civilisation, eventually replacing Memphis, Egypt, Memphis, in present-day Greater Cairo, as Egypt's capital. Called the "Bride of the Mediterranean" and "Pearl of the Mediterranean Coast" internationally, Alexandria is a popular tourist destination and an important industrial centre due to its natural gas and petroleum, oil pipeline transport, pipelines from Suez. The city extends about along the northern coast of Egypt and is the largest city on the Mediterranean, the List of cities and towns in Egypt#Largest cities, second-largest in Egypt (after Cairo), the List of largest cities in the Arab world, fourth- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barber
A barber is a person whose occupation is mainly to cut, dress, groom, style and shave hair or beards. A barber's place of work is known as a barbershop or the barber's. Barbershops have been noted places of social interaction and public discourse since at least classical antiquity. In some instances, barbershops were also public forums. They were the locations of open debates, voicing public concerns, and engaging citizens in discussions about contemporary issues. In previous times, barbers (known as barber surgeons) also performed surgery and dentistry. With the development of safety razors and the decreasing prevalence of beards in English-speaking world, Anglophonic cultures, most barbers now specialize in cutting men's scalp hair as opposed to facial hair. Names In modern times, the term "barber" is used both as a professional title and to refer to hairdressers who specialize in men's hair. Historically, all hairdressers were considered barbers. In the 20th century, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diogenes Laërtius
Diogenes Laërtius ( ; , ; ) was a biographer of the Greek philosophers. Little is definitively known about his life, but his surviving book ''Lives and Opinions of Eminent Philosophers'' is a principal source for the history of ancient Greek philosophy. His reputation is controversial among scholars because he often repeats information from his sources without critically evaluating it. In many cases, he focuses on insignificant details of his subjects' lives while ignoring important details of their philosophical teachings and he sometimes fails to distinguish between earlier and later teachings of specific philosophical schools. However, unlike many other ancient secondary sources, Diogenes Laërtius tends to report philosophical teachings without trying to reinterpret or expand on them, and so his accounts are often closer to the primary sources. Due to the loss of so many of the primary sources on which Diogenes relied, his work has become the foremost surviving source on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siphon
A siphon (; also spelled syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in an inverted "U" shape, which causes a liquid to flow upward, above the surface of a reservoir, with no pump, but powered by the fall of the liquid as it flows down the tube under the pull of gravity, then discharging at a level lower than the surface of the reservoir from which it came. There are two leading theories about how siphons cause liquid to flow uphill, against gravity, without being pumped, and powered only by gravity. The traditional theory for centuries was that gravity pulling the liquid down on the exit side of the siphon resulted in reduced pressure at the top of the siphon. Then atmospheric pressure was able to push the liquid from the upper reservoir, up into the reduced pressure at the top of the siphon, like in a barometer or drinking straw, and then over. However, it has been demo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christiaan Huygens
Christiaan Huygens, Halen, Lord of Zeelhem, ( , ; ; also spelled Huyghens; ; 14 April 1629 – 8 July 1695) was a Dutch mathematician, physicist, engineer, astronomer, and inventor who is regarded as a key figure in the Scientific Revolution. In physics, Huygens made seminal contributions to optics and mechanics, while as an astronomer he studied the rings of Saturn and discovered its largest moon, Titan (moon), Titan. As an engineer and inventor, he improved the design of telescopes and invented the pendulum clock, the most accurate timekeeper for almost 300 years. A talented mathematician and physicist, his works contain the first idealization of a physical problem by a set of Mathematical model, mathematical parameters, and the first mathematical and mechanistic explanation of an unobservable physical phenomenon.Dijksterhuis, F.J. (2008) Stevin, Huygens and the Dutch republic. ''Nieuw archief voor wiskunde'', ''5'', pp. 100–10/ref> Huygens first identified the correct la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulis
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 Gas compressor, 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 mec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
