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Ivan Kulibin
Ivan Petrovich Kulibin (April 21, 1735 – August 11, 1818) was a Russian mechanic and inventor. He was born in Nizhny Novgorod in the family of a trader. From childhood, Kulibin displayed an interest in constructing mechanics, mechanical tools. Soon, clock mechanisms became a special interest of his. His realizations as well as his prolific imagination inspired the work of many. Saint Petersburg years During 1764–1767 he built an egg (biology), egg-shaped clock, containing a complex automatic mechanism. In 1769 Kulibin gave this clock to Catherine the Great, Catherine II, who assigned Kulibin to be in charge of the mechanical workshop in the Russian Academy of Sciences, Academy of Sciences of Saint Petersburg (established in 1724). There, Kulibin built a “planetary” pocket-clock, which showed not only the current time, but also the month, day of the week, the season and the current moon phase. Kulibin also designed projects for tower clocks, miniature "clock-in-a-ring" t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flywheel
A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, assuming the flywheel's moment of inertia is constant (i.e., a flywheel with fixed mass and second moment of area revolving about some fixed axis) then the stored (rotational) energy is directly associated with the square of its rotational speed. Since a flywheel serves to store mechanical energy for later use, it is natural to consider it as a kinetic energy analogue of an electrical inductor. Once suitably abstracted, this shared principle of energy storage is described in the generalized concept of an accumulator. As with other types of accumulators, a flywheel inherently smooths sufficiently small deviations in the power output of a system, thereby effectively playing the role of a low-pass filter with respect to the mechanical velocity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piano
The piano is a stringed keyboard instrument in which the strings are struck by wooden hammers that are coated with a softer material (modern hammers are covered with dense wool felt; some early pianos used leather). It is played using a keyboard, which is a row of keys (small levers) that the performer presses down or strikes with the fingers and thumbs of both hands to cause the hammers to strike the strings. It was invented in Italy by Bartolomeo Cristofori around the year 1700. Description The word "piano" is a shortened form of ''pianoforte'', the Italian term for the early 1700s versions of the instrument, which in turn derives from ''clavicembalo col piano e forte'' (key cimbalom with quiet and loud)Pollens (1995, 238) and ''fortepiano''. The Italian musical terms ''piano'' and ''forte'' indicate "soft" and "loud" respectively, in this context referring to the variations in volume (i.e., loudness) produced in response to a pianist's touch or pressure on the keys: the grea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mill (grinding)
A mill is a device, often a structure, machine or kitchen appliance, that breaks solid materials into smaller pieces by grinding, crushing, or cutting. Such comminution is an important unit operation in many processes. There are many different types of mills and many types of materials processed in them. Historically mills were powered by hand or by animals (e.g., via a hand crank), working animal (e.g., horse mill), wind (windmill) or water (watermill). In modern era, they are usually powered by electricity. The grinding of solid materials occurs through mechanical forces that break up the structure by overcoming the interior bonding forces. After the grinding the state of the solid is changed: the grain size, the grain size disposition and the grain shape. Milling also refers to the process of breaking down, separating, sizing, or classifying aggregate material (e.g. mining ore). For instance rock crushing or grinding to produce uniform aggregate size for construction purp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic viability of investing in the equipment, labor, and energy required to extract, refine and transport the materials found at the mine to manufacturers who can use the material. Ores recovered by mining include metals, coal, oil shale, gemstones, limestone, chalk, dimension stone, rock salt, potash, gravel, and clay. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantities in seawater. The open ocean has about of solids per liter of sea water, a salinity of 3.5%. Salt is essential for life in general, and saltiness is one of the basic human tastes. Salt is one of the oldest and most ubiquitous food seasonings, and is known to uniformly improve the taste perception of food, including otherwise unpalatable food. Salting, brining, and pickling are also ancient and important methods of food preservation. Some of the earliest evidence of salt processing dates to around 6,000 BC, when people living in the area of present-day Romania boiled spring water to extract salts; a salt-works in China dates to approximately the same period. Salt was also prized by the ancient Hebrews, Greeks, Romans, Byzantines, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steam Engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be transformed, by a connecting rod and crank, into rotational force for work. The term "steam engine" is generally applied only to reciprocating engines as just described, not to the steam turbine. Steam engines are external combustion engines, where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In general usage, the term ''steam engine'' can refer to either complete steam plants (including boilers etc.), such as railway steam locomotives and portable engines, or may refer to the piston or turbine machinery alone, as in the beam engine and stationary steam engine. Although steam-driven devices were known as early as the aeolipile in the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamp Of USSR 1885
Stamp or Stamps or Stamping may refer to: Official documents and related impressions * Postage stamp, used to indicate prepayment of fees for public mail * Ration stamp, indicating the right to rationed goods * Revenue stamp, used on documents to indicate payment of tax * Rubber stamp, device used to apply inked markings to objects ** Passport stamp, a rubber stamp inked impression received in one's passport upon entering or exiting a country ** National Park Passport Stamps * Food stamps, tickets used in the United States that indicate the right to benefits in the Supplemental Nutrition Assistance Program Collectibles * Trading stamp, a small paper stamp given to customers by merchants in loyalty programs that predate the modern loyalty card * Eki stamp, a free collectible rubber ink stamp found at many train stations in Japan Places * Stamp Creek, a stream in Georgia * Stamps, Arkansas People * Stamp or Apiwat Ueathavornsuk (born 1982), Thai singer-songwriter * Stamp (surna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Cox (inventor)
James Cox (c. 1723–1800) was a British jeweller, goldsmith and entrepreneurJames Cox (ca. 1723–1800): Goldsmith and Entrepreneur Heilbrunn Timeline of Art History; Roger Smit "James Cox (c. 1723-1800): A Revised Biography" ''The Burlington Magazine'', Vol. 142, No. 1167 (Jun., 2000), pp. 353-361 and the proprietor of Cox's Museum. He is now best known for creating ingenious and mechanical clocks, including |
Peacock Clock
The Peacock Clock is a large automaton featuring three life-sized mechanical birds. It was manufactured by the entrepreneur James Cox in the 2nd half of the 18th century and through the influence of Grigory Potemkin it was acquired by Catherine the Great in 1781. Today it is a prominent exhibit in the collections of the Hermitage Museum in Saint Petersburg. The clock is also shown daily on the Russian TV channel Russia-K. References *Yuna Zek, Antonina Balina, Mikhail Guryev, Yuri Semionov''The Peacock Clock''– photos, history and description of the Peacock Clock at hermitagemuseum.org (website of the Hermitage Museum The State Hermitage Museum ( rus, Государственный Эрмитаж, r=Gosudarstvennyj Ermitaž, p=ɡəsʊˈdarstvʲɪn(ː)ɨj ɪrmʲɪˈtaʂ, links=no) is a museum of art and culture in Saint Petersburg, Russia. It is the list of ..., archived version) {{commonscat, Hermitage Peacock clock Peacock Clock 18th-century robots Collection of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telegraph
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] |
Elevator
An elevator or lift is a wire rope, cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or deck (building), decks of a building, watercraft, vessel, or other structure. They are typically powered by electric motors that drive traction cables and counterweight systems such as a hoist (device), hoist, although some pump hydraulic fluid to raise a cylindrical piston like a hydraulic jack, jack. In agriculture and manufacturing, an elevator is any type of conveyor device used to lift materials in a continuous stream into bins or silos. Several types exist, such as the chain and bucket elevator, grain auger screw conveyor using the principle of Archimedes' screw, or the chain and paddles or forks of hay elevators. Languages other than English, such as Japanese, may refer to elevators by loanwords based on either ''elevator'' or ''lift''. Due to wheelchair access laws, elevators are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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