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Beverly Clock
The Beverly Clock is a clock in the 3rd-floor lift foyer of the Department of Physics at the University of Otago, Dunedin, New Zealand. The clock is still running despite never having been manually wound since its construction in 1864 by Arthur Beverly. Operation The clock's mechanism is driven by variations in daily temperature and, to a lesser extent, in atmospheric pressure. Either causes the air in a airtight box to expand or contract, which pushes on a diaphragm. A temperature variation of over the course of each day creates approximately enough pressure to raise a one-pound weight by one inch (equivalent to ), which drives the clock mechanism. A similar mechanism in a commercially available clock that operates on the same principle is the Atmos clock, manufactured by the Swiss watchmaker Jaeger-LeCoultre. While the clock has not been wound since it was made, it has stopped on a number of occasions, such as when its mechanism needed cleaning or there was a mechanical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmos Clock
Atmos is the brand name of a mechanical torsion pendulum clock manufactured by Jaeger-LeCoultre in Switzerland. The clock gets the energy it needs to run from temperature changes in the environment and does not need to be wound manually. It can run for years without human intervention. The mechanism is driven by a mainspring, which is wound by the expansion and contraction of liquid and gaseous ethyl chloride in an internal hermetically sealed metal bellows. The ethyl chloride vaporises into an expansion chamber as the temperature rises, compressing a spiral spring; with a fall in temperature the gas condenses and the spiral spring expands, winding the mainspring. This motion constantly winds the mainspring. A temperature variation of only one degree in the range between and , or a pressure variation of 3 mmHg, was calculated to provide energy for two days' operation for an early prototype, while for a more recent Atmos 540 model the corresponding value has been computed as 4.3 d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Physics
Physics is a branch of science in which the primary objects of study are matter and energy. These topics were discussed across many cultures in ancient times by philosophers, but they had no means to distinguish causes of natural phenomena from superstitions. The Scientific Revolution of the 17th century, especially the discovery of the law of gravity, began a process of knowledge accumulation and specialization that gave rise to the field of physics. Mathematical advances of the 18th century gave rise to classical mechanics, and the increased used of the experimental method led to new understanding of thermodynamics. In the 19th century, the basic laws of electromagnetism and statistical mechanics were discovered. At the beginning of the 20th century, physics was transformed by the discoveries of quantum mechanics, relativity, and atomic theory. Physics today may be divided loosely into classical physics and modern physics. Ancient history Elements of what became phys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annals Of Improbable Research
The ''Annals of Improbable Research'' (''AIR'') is a bimonthly magazine devoted to scientific humor, in the form of a satirical take on the standard academic journal. ''AIR'', published six times a year since 1995, usually showcases at least one piece of scientific research being done on a strange or unexpected topic, but most of their articles concern real or fictional absurd experiments, such as a comparison of apples and oranges using infrared spectroscopy. Other features include such things as ratings of the cafeterias at scientific institutes, fake classifieds and advertisements for a medical plan called HMO-NO, and a very odd letters page. The magazine is headquartered in Cambridge, Massachusetts. ''AIR'' awards the annual science Ig Nobel Prizes, for ten achievements that "first make people laugh, and then make them think". ''AIR'' also runs the Luxuriant Flowing Hair Club for Scientists. History ''AIR'' is not the first science parody magazine. The '' Journal of Irrep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Glider
An underwater glider is a type of autonomous underwater vehicle (AUV) that employs variable-buoyancy propulsion instead of traditional propellers or Underwater thruster, thrusters. It employs variable buoyancy in a similar way to a profiling float, but unlike a float, which can move only up and down, an underwater glider is fitted with hydrofoils (underwater wings) that allow it to Gliding flight, glide forward while descending through the water. At a certain depth, the glider switches to positive buoyancy to climb back up and forward, and the cycle is then repeated. While not as fast as conventional AUVs, gliders offer significantly greater range and endurance compared to traditional AUVs, extending ocean sampling missions from hours to weeks or months, and to thousands of kilometers of range. The typical up-and-down, Sawtooth wave, sawtooth-like profile followed by a glider can provide data on temporal and spatial scales unattainable by powered AUVs and much more costly to sampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clock Of The Long Now
The Clock of the Long Now, also called the 10,000-year clock, is a mechanical clock under construction that is designed to keep time for 10,000 years. It is being built by the Long Now Foundation. A two-meter prototype is on display at the Science Museum in London. , two more prototypes are on display at The Long Now Museum & Store at Fort Mason Center in San Francisco. The project was conceived by Danny Hillis in 1989. The first prototype of the clock began working on December 31, 1999, just in time to display the transition to the year 2000. At midnight on New Year's Eve, the date indicator changed from 01999 to 02000, and the chime struck twice. The manufacture and site construction of the first full-scale prototype clock is being funded by Jeff Bezos's investment firm Bezos Expeditions, with $42 million, and is on land which Bezos owns in the Sierra Diablo mountains in Texas. Purpose In the words of Stewart Brand, a founding board member of the foundation, "Such a cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cox's Timepiece
Cox's timepiece is a clock developed in the 1760s by James Cox (inventor), James Cox. It was developed in collaboration with John Joseph Merlin (with whom Cox also worked on developing automata). Cox claimed that his design was a true perpetual motion machine, but as the device is powered from changes in atmospheric pressure via a mercury (element), mercury barometer, this is not the case. The clock still exists, but was deactivated at the time of its relocation to the Victoria and Albert Museum in London. Design and history The clock is similar to other mechanical clocks, except that it Automatic watch, does not need winding. The change of pressure in the Earth's atmosphere acts as an external energy source and causes sufficient movement of the winding mechanism. This keeps the mainspring coiled inside the barrel. The clock is designed to enable the timepiece to run indefinitely and overwinding is prevented by a safety mechanism. The Wiktionary:prime mover, prime mover, encased ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pitch Drop Experiment
A pitch drop experiment is a long-term experiment which measures the flow of a piece of pitch over many years. "Pitch" is the name for any of a number of highly viscous liquids which appear solid, most commonly bitumen, also known as asphalt. At room temperature, tar pitch flows at a very low rate, taking several years to form a single drop. University of Queensland experiment The best-known version of the experiment was started in 1927 by Thomas Parnell of the University of Queensland in Brisbane, Australia, to demonstrate to students that some substances which appear solid are highly viscous fluids. Parnell poured a heated sample of the pitch into a sealed funnel and allowed it to settle for three years. In 1930, the seal at the neck of the funnel was cut, allowing the pitch to start flowing. A glass dome covers the funnel and it is placed on display outside a lecture theatre. Each droplet forms and falls over a period of about a decade. Between 1961 and 2013, the experi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford Electric Bell
The Oxford Electric Bell or Clarendon Dry Pile is an experimental electric bell, in particular a type of bell that uses the electrostatic clock principle that was set up in 1840 and which has run nearly continuously ever since. It was one of the first pieces purchased for a collection of apparatus by clergyman and physicist Robert Walker. It is located in a corridor adjacent to the foyer of the Clarendon Laboratory at the University of Oxford, England, and is still ringing every half second, albeit inaudibly due to being behind two layers of glass. Design The experiment consists of two brass bells, each positioned beneath a dry pile (a form of battery), the pair of piles connected in series, giving the bells opposite electric charges. The clapper is a metal sphere approximately in diameter suspended between the piles, which rings the bells alternately due to electrostatic forces. When the clapper touches one bell, it is charged by that pile. It is then repelled from that b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jaeger-LeCoultre
Manufacture Jaeger-LeCoultre SA, or simply Jaeger-LeCoultre (), is a Swiss luxury watch and clock manufacturer founded by Antoine LeCoultre in 1833 and is based in Le Sentier, Switzerland. Since 2000, the company has been a fully owned subsidiary of the Swiss luxury group Richemont. Jaeger-LeCoultre is regarded as a top-tier Richemont brand. It has hundreds of inventions, patents, and more than one thousand Movement (clockwork), movements to its name, including the world's smallest movement, one of the world's most complicated wristwatches (Grande Complication), and a timepiece of Perpetual motion, near-perpetual movement (the ''Atmos clock''). Watch enthusiasts refer to the brand as the watchmaker's watchmaker. History Early history The earliest records of the LeCoultre family in Switzerland date from the 16th century, when Pierre LeCoultre (circa 1530 – circa 1600), a French Huguenot, fled to Geneva from Lizy-sur-Ourcq, France to escape religious persecution. In 1558, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pound (mass)
The pound or pound-mass is a unit of mass used in both the British imperial and United States customary systems of measurement. Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly , and which is divided into 16 avoirdupois ounces. The international standard symbol for the avoirdupois pound is lb; an alternative symbol (when there might otherwise be a risk of confusion with the pound-force) is lbm (for most pound definitions), # ( chiefly in the U.S.), and or ̶ (specifically for the apothecaries' pound). The unit is descended from the Roman (hence the symbol ''lb'', descended from the scribal abbreviation, '). The English word ''pound'' comes from the Roman ('the weight measured in '), and is cognate with, among others, German , Dutch , and Swedish . These units are now designated as historical and are no longer in common usage, being replaced by the metric system. Usage of the un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
