The GN was a British cyclecar made in London, between 1910 and 1925, The name derived from its founders, H. R. Godfrey and Archibald Frazer-Nash. Production ceased in 1923 but the company kept trading until 1925; the GN cyclecar was made in Hendon, North London, between 1910 and 1925 moving to Wandsworth, London. The name derives from its founders, H. R. Godfrey and Archibald Frazer-Nash. Production ceased in 1923 but the company kept trading until 1925. After making several cars for their own use, the two founders launched the GN car in 1909, building them in the stables at the Frazer Nash family home; the car was powered by a V twin engine by Peugeot with belt drive to the rear wheels. By 1911, production had moved to Hendon and GN's own 1100 cc engine, using some Peugeot parts being fitted; the engine was mounted in the chassis with the crankshaft parallel to the front axle, driving through a two-speed transmission by chain and dog clutch by belt to the rear wheels. The two-seat car was light, weighing only about 180 kg.
Therefore, in spite of the low power available, 60 mph was achievable, respectable performance for the time. The engine was turned 90 degrees in 1913, with its cylinder heads protruding through the bonnet sides, a team was entered into the French Cyclecar Grand Prix resulting, in sports models being added to the range; some 200 cars had been made when production stopped with the outbreak of World War I. Production restarted in 1919, shortly afterward the company was bought by British Grégoire Ltd and moved to East Hill, Wandsworth in south west London; the chassis changed from wood to steel, with the chain type transmission now with three speeds and reverse. At the peak, 500 staff were employed. A licence to make the cars was agreed with the French maker Salmson. By 1921, the cyclecar boom was on the wane and the company went into receivership, but was soon sold; the new owner, a Mr Black, wanted to move to much higher production levels and away from sports cars. A four-cylinder water-cooled model with 1098 cc DFP engine and shaft drive to a differential on the solid rear axle was introduced in 1922 as part of the new policy, Godfrey and Frazer Nash left the company that year.
In 1923 a Chapuis-Dornier engine replaced the DFP, but production of the new car and the old V twin model stopped in May. About 4000 cars of all types were made by GN in the post war period. A new company was founded by some ex-employees and a few more cars were made from parts in 1924 and 1925, but the main business was spares and service. In 1925 the company became General Motors dealers. H. R. Godfrey went on to found a new car company, Godfrey-Proctor, HRG. Frazer Nash formed the car maker that took his name where he re-introduced his chain and clutch transmission system; the most notable racing GNs were Archie Fraser-Nash's "Mowgli", "Kim" and Basil Davenport's "Spider", "BHD" and his "Big Spider". Other famous pre war "GN Specials" were "Wasp", "Wilkes-GN", "GNat", "Martyr", "The Becke Powerplus", "The Wilkes GN" "The Chawner GN", "Grasshopper" & "COGNAC", all of them successful hill climb cars of the 1920s and 1930s. Many still compete today, alongside a number of machines constructed from period parts.
Spider was an successful sprint car and held the outright record at Shelsley Walsh Speed Hill Climb several times in the 1920s. A doggerel rhyme of the time went: Godfrey hated cogs, Built a car with chains and dogs, and it worked, but would it if They had built it with a diff Beaulieu Encyclopedia of the Automobile. Editor G. N. Georgano; the Stationery Office, 2000. ISBN 1-57958-293-1 A-Z of Cars of the 1920s. Nick Baldwin. Bay View Books 1989. ISBN 1-870979-53-2 Official website of the Frazer Nash Car Club
Differential (mechanical device)
A differential is a gear train with three shafts that has the property that the rotational speed of one shaft is the average of the speeds of the others, or a fixed multiple of that average. In automobiles and other wheeled vehicles, the differential allows the outer drive wheel to rotate faster than the inner drive wheel during a turn; this is necessary when the vehicle turns, making the wheel, travelling around the outside of the turning curve roll farther and faster than the other. The average of the rotational speed of the two driving wheels equals the input rotational speed of the drive shaft. An increase in the speed of one wheel is balanced by a decrease in the speed of the other; when used in this way, a differential couples the longitudinal input propellor shaft to the pinion, which in turn drives the transverse ring gear of the differential. This usually works as reduction gearing. On rear wheel drive vehicles the differential may connect to half-shafts inside an axle housing, or drive shafts that connect to the rear driving wheels.
Front wheel drive vehicles tend to have the engine crankshaft and the gearbox shafts transverse, with the pinion on the end of the main-shaft of the gearbox and the differential enclosed in the same housing as the gearbox. There are individual drive-shafts to each wheel. A differential consists of one input, the drive shaft, two outputs which are the two drive wheels, however the rotation of the drive wheels are coupled to each other by their connection to the roadway. Under normal conditions, with small tyre slip, the ratio of the speeds of the two driving wheels is defined by the ratio of the radii of the paths around which the two wheels are rolling, which in turn is determined by the track-width of the vehicle and the radius of the turn. Non-automotive uses of differentials include performing analog arithmetic. Two of the differential's three shafts are made to rotate through angles that represent two numbers, the angle of the third shaft's rotation represents the sum or difference of the two input numbers.
The earliest known use of a differential gear is in the Antikythera mechanism, circa 80 BCE, which used a differential gear to control a small sphere representing the moon from the difference between the sun and moon position pointers. The ball was painted black and white in hemispheres, graphically showed the phase of the moon at a particular point in time. An equation clock that used a differential for addition was made in 1720. In the 20th Century, large assemblies of many differentials were used as analog computers, for example, the direction in which a gun should be aimed. However, the development of electronic digital computers has made these uses of differentials obsolete. Military uses may still exist, for example, for a hypothetical computer designed to survive an electromagnetic pulse. All the differentials that are now made are used in automobiles and similar vehicles including offroad vehicles such as ATVs. There are many claims to the invention of the differential gear, but it is possible that it was known, at least in some places, in ancient times.
Some historical milestones of the differential include: 100 BC–70 BC: The Antikythera mechanism has been dated to this period. It was discovered in 1902 on a shipwreck by sponge divers, modern research suggests that it used a differential gear to determine the angle between the ecliptic positions of the Sun and Moon, thus the phase of the Moon. 227–239 AD: Ma Jun from the Kingdom of Wei in China invents the first verifiable south-pointing chariot, which provided cardinal direction as a non-magnetic, mechanized compass. Some such chariots may have used differential gears. 658, 666 AD: two Chinese Buddhist monks and engineers create south-pointing chariots for Emperor Tenji of Japan. 1027, 1107 AD: Documented Chinese reproductions of the south-pointing chariot by Yan Su and Wu Deren, which described in detail the mechanical functions and gear ratios of the device much more so than earlier Chinese records. 1720: Joseph Williamson uses a differential gear in a clock. 1810: Rudolph Ackermann of Germany invents a four-wheel steering system for carriages, which some writers mistakenly report as a differential.
1827: modern automotive differential patented by watchmaker Onésiphore Pecqueur of the Conservatoire National des Arts et Métiers in France for use on a steam wagon. 1832: Richard Roberts of England patents "gear of compensation", a differential for road locomotives. 1874: Aveling and Porter of Rochester, Kent list a crane locomotive in their catalogue fitted with their patent differential gear on the rear axle. 1876: James Starley of Coventry invents chain-drive differential for use on bicycles. 1897: first use of differential on an Australian steam car by David Shearer. 1958: Vernon Gleasman patents the Torsen dual-drive differential, a type of limited-slip differential that relies on the action of gearing, instead of a combination of clutches and gears. An epicyclic differential can use epicyclic gearing to split and apportion torque asymmetrically between the front and rear axles. An epicyclic differential is at the heart of the Toyota Prius automotive drive train, where it interconnects the engine, motor-generators, the drive wheels.
It has the advantage of being compact along the length of its axis. Epicyclic gears are called planetary gears because the axes of the planet gears revolve around the common axis of the sun and ring gears that they mesh with and roll between. In the image, the yellow shaft carries the sun gear, hidden. T
An armillary sphere is a model of objects in the sky, consisting of a spherical framework of rings, centred on Earth or the Sun, that represent lines of celestial longitude and latitude and other astronomically important features, such as the ecliptic. As such, it differs from a celestial globe, a smooth sphere whose principal purpose is to map the constellations, it was invented separately in ancient Greece and ancient China, with use in the Islamic world and Medieval Europe. With the Earth as center, an armillary sphere is known as Ptolemaic. With the Sun as center, it is known as Copernican; the flag of Portugal features an armillary sphere. The armillary sphere is featured in Portuguese heraldry, associated with the Portuguese discoveries during the Age of Exploration. In the flag of the Empire of Brazil, the armillary sphere is featured; this section refers to labels in the diagram below. The exterior parts of this machine are a compages of brass rings, which represent the principal circles of the heavens.
The equinoctial A, divided into 360 degrees for showing the sun's right ascension in degrees. The ecliptic B, divided into 12 signs, each sign into 30 degrees, into the months and days of the year; the tropic of Cancer C, touching the ecliptic at the beginning of Cancer in e, the tropic of Capricorn D, touching the ecliptic at the beginning of Capricorn in f. The Arctic Circle E, the Antarctic Circle F, each 23½ degrees from its respective pole at N and S; the equinoctial colure G, passing through the north and south poles of the heaven at N and S, through the equinoctial points Aries and Libra, in the ecliptic. The solstitial colure H, passing through the poles of the heaven, through the solstitial points Cancer and Capricorn, in the ecliptic; each quarter of the former of these colures is divided into 90 degrees, from the equinoctial to the poles of the world, for showing the declination of the sun and stars. In the north pole of the ecliptic is a nut b, to, fixed one end of the quadrantal wire, to the other end a small sun Y, carried round the ecliptic B—B, by turning the nut: and in the south pole of the ecliptic is a pin d, on, another quadrantal wire, with a small moon Ζ upon it, which may be moved round by hand: but there is a particular contrivance for causing the moon to move in an orbit which crosses the ecliptic at an angle of 5⅓ degrees, to opposite points called the moon's nodes.
Within these circular rings is a small terrestrial globe I, fixed on an axis K, which extends from the north and south poles of the globe at n and s, to those of the celestial sphere at N and S. On this axis is fixed the flat celestial meridian L L, which may be set directly over the meridian of any place on the globe, so as to keep over the same meridian upon it; this flat meridian is graduated the same way as the brass meridian of the common globe, its use is much the same. To this globe is fitted the movable horizon M, so as to turn upon the two strong wires proceeding from its east and west points to the globe, entering the globe at the opposite points off its equator, a movable brass ring set into the globe in a groove all around its equator; the globe may be turned by hand within this ring, so as to place any given meridian upon it, directly under the celestial meridian L. The horizon is divided into 360 degrees all around its outermost edge, within which are the points of the compass, for showing the amplitude of the sun and the moon, both in degrees and points.
The celestial meridian L passes through two notches in the north and south points of the horizon, as in a common globe: both here, if the globe be turned round, the horizon and meridian turn with it. At the south pole of the sphere is a circle of 25 hours, fixed to the rings, on the axis is an index which goes round that circle, if the globe be turned round its axis; the whole fabric is supported on a pedestal N, may be elevated or depressed upon the joint O, to any number of degrees from 0 to 90, by means of the arc P, fixed in the strong brass arm Q, slides in the upright piece R, in, a screw at r, to fix it at any proper elevation. In the box T are two wheels and two pinions, whose axes come out at V and U; when the winch is put upon the axis V, turn backward, the terrestrial globe, with its horizon and celestial meridian, keep at rest. But when the winch is put upon the axis U, turned forward, the sphere with the sun and moon keep at rest. If the earthly globe be turned, the hour-index goes round its hour-circle.
Mack Trucks, Inc. is an American truck–manufacturing company and a former manufacturer of buses and trolley buses. Founded in 1900 as the Mack Brothers Company, it manufactured its first truck in 1907 and adopted its present name in 1922. Mack Trucks is a subsidiary of AB Volvo which purchased Mack along with Renault Trucks in 2000. After being founded in Brooklyn, New York, the company's headquarters were in Allentown, Pennsylvania from 1905 to 2009 when they moved to Greensboro, North Carolina; the entire line of Mack products is still produced in Lower Macungie, with additional assembly plants in Pennsylvania, Maryland and Venezuela. There was a Mack plant in Hayward, California; the company's manufacturing facilities are located at Lehigh Valley Operations formally known as the Macungie Assembly Operations Plant in Lower Macungie Township, Pennsylvania. Mack Trucks is one of the top producers in the vocational and on-road vehicle market, class 8 through class 13. Mack trucks have been sold in 45 countries.
Located near its former Allentown corporate headquarters, The Macungie, Pennsylvania manufacturing plant produces all Mack products including Mack MP-series engines. According to local historians, Mack transmissions, TC-15 transfer cases, rear engine power take-offs are designed and manufactured in Hagerstown, the original factory location. Parts for Mack's right-hand-drive vehicles are produced in Brisbane, Australia for worldwide distribution. Assembly for South America is done at Mack de Venezuela C. A. in Caracas, Venezuela. The Venezuela operation is a complete knock down facility. Components are shipped from the United States to Caracas for final assembly. In addition to its Macungie manufacturing facility, Mack has a remanufacturing center in Middletown, Pennsylvania. On August 14, 2008, Mack Trucks announced a major restructuring plan that included: Relocation of Mack's head office, product development, most support functions, purchasing functions to Greensboro, North Carolina, in 2009.
Mack's parent, Volvo Trucks has its North American base in Greensboro. Assembly of all produced Mack highway vehicles in Macungie, Pennsylvania from 2008 Mack's testing facility in Allentown, being converted into a "customer demonstration/reception center" in 2010 Restructuring the parts distribution network by 2010 ° This is a timeline of Mack Trucks history. Most of the information is taken from the Mack history page at MackTrucks.com, unless otherwise noted. 1890: John M. Mack gets a job at Fallesen & Berry, a carriage and wagon company in Brooklyn, New York. 1893: John Mack and his brother Augustus F. Mack buy Fallesen & Berry. 1894: A third Mack brother, William C. Mack joins his brothers in the company's operations; the Macks explore working with steam powered and electric motor cars. 1900: The Macks open their first bus manufacturing plant. Ordered by a sightseeing company, the first "Mack bus" is delivered. 1902: The Mack Brothers Company is established in New York. 1904: Mack Brothers introduces the brand name "Manhattan" on its products.
1905: Allentown is selected as the home of main manufacturing operations, headquarters. A fourth Mack brother, Joseph Mack becomes a stockholder. Mack begins making rail cars and locomotives. 1910: The "Manhattan" brand trucks are redesignated "Mack" trucks. A fifth Mack brother Charles Mack joins the company. 1911: Headed by C. P. Coleman, The Saurer Motor Truck Company acquires rights to manufacture and sell heavy trucks under the Saurer brand name at its plant in Plainfield, New Jersey. On September 23, 1911, the Saurer Motor Truck Company merges with the Mack Brothers Motor Car Company of Allentown headed by J. M. Mack, forming the International Motor Truck Company. IMTC continues to make and sell trucks using the Saurer name until 1918. In 1911, IMTC is capitalized at $2.6 million total. 1912: Brothers John and Joseph Mack leave the company. 1919: The United States Army conducts a transcontinental project using Mack Trucks to study the need for and feasibility of a new interstate highway system.
1922: The company name is changed to Mack Trucks, Inc. The bulldog is established as the company's corporate symbol. 1924: John Mack dies in a car crash in Weatherly, Pennsylvania. 1932: While recuperating from an operation, Mack's chief engineer Alfred Fellows Masury carves Mack's first bulldog hood ornament. Masury applies for and receives a U. S. patent for his design. 1933: Mack Trucks are used in building of many ambitious construction projects for the Work Projects Administration including the Hoover Dam. 1941: Fire Apparatus manufacturing is moved from Allentown, Pennsylvania, to Long Island City, in Queens, New York. 1951: Fire Apparatus manufacturing is moved from Long Island City back to Allentown 1956: Mack Trucks, Inc. buys Brockway Motor Company.. 1966: Mack begins production at its new assembly plant in Oakville, Canada. The facility is closed in 1993. 1967: Mack Trucks becomes a part of the Signal Oil and Gas Company in a one-for-one exchange for cumulative convertible preferred stock.
That year Signal changes its name to Signal Companies. 1970: Mack moves into its new Allentown world headquarters. 1979: Renault buys a 10% shareholding 1982: Renault increases its shareholding to 20%, Signal reduces its stake to 10%. 1983: Mack Trucks conducts an IPO, issuing 15.7 million shares of common stock. Renault increases its holdings to 40% and Signal reduces its stake to 10.3% ownership. 1987: Renault reorganizes.
History of Greece
The history of Greece encompasses the history of the territory of the modern nation state of Greece as well as that of the Greek people and the areas they inhabited and ruled historically. The scope of Greek habitation and rule has varied throughout the ages and as a result the history of Greece is elastic in what it includes; the history of Greece is divided into the following periods: Neolithic Greece covering a period beginning with the establishment of agricultural societies in 7000 BC and ending in 3200/3100 BC, Helladic chronology covering a period beginning with the transition to a metal-based economy in 3200/3100 BC to the rise and fall of the Mycenaean Greek palaces spanning five centuries, Ancient Greece covering a period from the fall of the Mycenaean civilization in 1100 BC to 146 BC spanning multiple sub-periods including the Greek Dark Ages, Archaic period, the Classical period and the Hellenistic period, Roman Greece covering a period from the Roman conquest of Greece in 146 BC to 324 AD, Byzantine Greece covering a period from the establishment of the capital city of Byzantium, Constantinople, in 324 AD until the fall of Constantinople in 1453 AD, Ottoman Greece covering a period from 1453 up until the Greek Revolution of 1821, Modern Greece covering a period from 1821 to the present.
At its cultural and geographical peak, Greek civilization spread from Greece to Egypt and to the Hindu Kush mountains in Afghanistan. Since Greek minorities have remained in former Greek territories and Greek emigrants have assimilated into differing societies across the globe. Nowadays most Greeks live in the modern states of Cyprus; the Neolithic Revolution reached Europe beginning in 7000–6500 BC when agriculturalists from the Near East entered the Greek peninsula from Anatolia by island-hopping through the Aegean Sea. The earliest Neolithic sites with developed agricultural economies in Europe dated 8500–9000 BPE are found in Greece; the first Greek-speaking tribes, speaking the predecessor of the Mycenaean language, arrived in the Greek mainland sometime in the Neolithic period or the Early Bronze Age. The transition from the Greek Neolithic to the Early Bronze Age occurred when Greece's agricultural population began to import bronze and copper and used basic bronze-working techniques. During the end of the 3rd millennium BC, the indigenous inhabitants of mainland Greece underwent a cultural transformation attributed to climate change, local events and developments, as well as to continuous contacts with various areas such as western Asia Minor, the Cyclades and Dalmatia.
The Cycladic culture is a significant Late Neolithic and Early Bronze Age culture, is best known for its schematic flat female idols carved out of the islands' pure white marble centuries before the great Middle Bronze Age culture arose in Crete, to the south. The Minoan civilization in Crete, which lasted from about c. 3000 BC to c. 1400 BC, the Helladic culture on the Greek mainland from circa 3200/3100 BC to 2000/1900 BC. Little specific information is known about the Minoans, including their written system, recorded on the undeciphered Linear A script and Cretan hieroglyphs, they were a mercantile people engaged in extensive overseas trade throughout the Mediterranean region. Minoan civilization was affected by a number of natural cataclysms such as the volcanic eruption at Thera and earthquakes. In 1425 BC, the Minoan palaces were devastated by fire, which allowed the Mycenaean Greeks, influenced by the Minoans' culture, to expand into Crete; the Minoan civilization which preceded the Mycenaean civilization on Crete was revealed to the modern world by Sir Arthur Evans in 1900, when he purchased and began excavating a site at Knossos.
Mycenaean civilization originated and evolved from the society and culture of the Early and Middle Helladic periods in mainland Greece. It emerged in circa 1600 BC, when Helladic culture in mainland Greece was transformed under influences from Minoan Crete and lasted until the collapse of the Mycenaean palaces in c. 1100 BC. Mycenaean Greece is the Late Helladic Bronze Age civilization of Ancient Greece and it is the historical setting of the epics of Homer and most of Greek mythology and religion; the Mycenaean period takes its name from the archaeological site Mycenae in the northeastern Argolid, in the Peloponnesos of southern Greece. Athens, Pylos and Tiryns are important Mycenaean sites. Mycenaean civilization was dominated by a warrior aristocracy. Around 1400 BC, the Mycenaeans extended their control to Crete, center of the Minoan civilization, adopted a form of the Minoan script called Linear A to write their early form of Greek; the Mycenaean-era script is called Linear B, deciphered in 1952 by Michael Ventris.
The Mycenaeans buried their nobles in beehive tombs, large circular burial chambers with a high-vaulted roof and straight entry passage lined with stone. They buried daggers or some other form of military equipment with the deceased; the nobility were buried with gold masks, tiaras and jeweled weapons. Mycenaeans were buried in a sitting position, some of the nobility underwent mummification. Around 1100–1050 BC, the Mycenaean civilization collapsed. Numerous cities were sacked and the region entered what historians se
Clock towers are a specific type of building which houses a turret clock and has one or more clock faces on the upper exterior walls. Many clock towers are freestanding structures but they can adjoin or be located on top of another building. Clock towers are a common sight in many parts of the world with some being iconic buildings. One example is the Elizabeth Tower in London. There are many structures which may have clocks or clock faces attached to them and some structures have had clocks added to an existing structure. According to the Council on Tall Buildings and Urban Habitat a building is defined as a building if at least fifty percent of its height is made up of floor plates containing habitable floor area. Structures that do not meet this criterion, are defined as towers. A clock tower fits this definition of a tower and therefore can be defined as any tower built with one or more clock faces and that can be either freestanding or part of a church or municipal building such as a town hall.
Not all clocks on buildings therefore make the building into a clock tower. The mechanism inside the tower is known as a turret clock, it marks the hour by sounding large bells or chimes, sometimes playing simple musical phrases or tunes. Although clock towers are today admired for their aesthetics, they once served an important purpose. Before the middle of the twentieth century, most people did not have watches, prior to the 18th century home clocks were rare; the first clocks didn't have faces, but were striking clocks, which sounded bells to call the surrounding community to work or to prayer. They were therefore placed in towers. Clock towers were placed near the centres of towns and were the tallest structures there; as clock towers became more common, the designers realized that a dial on the outside of the tower would allow the townspeople to read the time whenever they wanted. The use of clock towers dates back to the antiquity; the earliest clock tower was the Tower of the Winds in Athens.
In its interior, there was a water clock, driven by water coming down from the Acropolis. In Song China, an astronomical clock tower was designed by Su Song and erected at Kaifeng in 1088, featuring a liquid escapement mechanism. In England, a clock was put up in a clock tower, the medieval precursor to Big Ben, at Westminster, in 1288; the oldest surviving turret clock part of a clock tower in Europe is the Salisbury cathedral clock, completed in 1306. Al-Jazari constructed an elaborate clock and described it in his Book of Knowledge of Ingenious Mechanical Devices in 1206, it was about 3.3 metres high, had multiple functions alongside timekeeping. It included a display of the zodiac and the solar and lunar paths, a pointer in the shape of the crescent moon which travelled across the top of a gateway, moved by a hidden cart and causing automatic doors to open, each revealing a mannequin, every hour, it was possible to re-program the length of day and night daily in order to account for the changing lengths of day and night throughout the year, it featured five robotic musicians who automatically play music when moved by levers operated by a hidden camshaft attached to a water wheel.
Other components of the castle clock included a main reservoir with a float, a float chamber and flow regulator and valve trough, two pulleys, crescent disc displaying the zodiac, two falcon automata dropping balls into vases. Line synchronous tower clocks were introduced in the United States in the 1920s; some clock towers have become famous landmarks. Prominent examples include Elizabeth Tower built in 1859, which houses the Great Bell in London, the tower of Philadelphia City Hall, the Rajabai Tower in Mumbai, the Spasskaya Tower of the Moscow Kremlin, the Torre dell'Orologio in the Piazza San Marco in Venice and the Zytglogge clock tower in the Old City of Bern, Switzerland; the tallest freestanding clock tower in the world is the Joseph Chamberlain Memorial Clock Tower at the University of Birmingham in Birmingham, United Kingdom. The tower stands at 100 metres tall and was completed in 1908; the clock tower of Philadelphia City Hall was part of the tallest building in the world from 1894, when the tower was topped out and the building occupied, until 1908.
Taller buildings have had clock faces added to their existing structure such as the Palace of Culture and Science in Warsaw, with a clock added in 2000. The building has a roof height of 187.68 m, an antenna height of 237 m. The NTT Docomo Yoyogi Building in Tokyo, with a clock added in 2002, has a roof height of 240 m, an antenna height of 272 m; the Abraj Al Bait, a hotel complex in Mecca constructed in 2012, has the largest and highest clock face on a building in the world, with its Makkah Royal Clock Tower having an occupied height of 494.4 m, a tip height of 601 m. The tower has four clock faces. List of clock towers Bell tower Minaret Street clock Thirteenth stroke of the clock Towerclocks.org - Tower clocks database Railway Station Clock Towers Architecture of time
Kaifeng, known by several names, is a prefecture-level city in east-central Henan province, China. It is one of the Eight Ancient Capitals of China, for being the capital seven times in history, is most famous for being the capital of China in the Northern Song dynasty. There are about 5 million people living in its metropolitan area. Located along the southern bank of the Yellow River, it borders the provincial capital of Zhengzhou to the west, Xinxiang to the northwest, Shangqiu to the east, Zhoukou to the southeast, Xuchang to the southwest, Heze of Shandong to the northeast; the postal romanization for the city is "Kaifeng". Its official one-character abbreviation in Chinese is 汴, it has been known as Dàliáng Biànliáng Biànzhōu Nánjīng Dōngjīng Biànjīng The name "Kaifeng" first appeared as the area's name after the Qin's conquest of China in the second century BC and means "expand the borders" and figuratively "hidden" and "vengeance". Its name was Qifeng, but the syllable qi was changed to the synonymous kai （/*Nə-ʰˤəj/, /*ʰˤəj/） to avoid the naming taboo of Liu Qi.
The prefecture-level city of Kaifeng administers five districts and four counties: Gulou District Longting District Yuwangtai District Xiangfu District Shunhe Hui District Weishi County Qi County Tongxu County Lankao County Kaifeng is one of the Eight Ancient Capitals of China. As with Beijing, there have been many reconstructions during its history. In 364 BC during the Warring States period, the State of Wei founded a city called Daliang as its capital in this area. During this period, the first of many canals in the area was constructed linking a local river to the Yellow River; when the State of Wei was conquered by the State of Qin, Kaifeng was destroyed and abandoned except for a mid-sized market town, which remained in place. Early in the 7th century, Kaifeng was transformed into a major commercial hub when it was connected to the Grand Canal as well as through the construction of a canal running to western Shandong. In 781 during the Tang dynasty, a new city was named Bian. Bian was the capital of the Later Jin, Later Han, Later Zhou of the Five Dynasties and Ten Kingdoms period.
The Song dynasty made Bian its capital when it overthrew the Later Zhou in 960. Shortly afterwards, the city underwent further expansion. During the Song, when it was known as Dongjing or Bianjing, Kaifeng was the capital, with a population of over 400,000 living both inside and outside the city wall. Typhus was an acute problem in the city; the historian Jacques Gernet provides a lively picture of life in this period in his Daily Life in China on the Eve of the Mongol Invasion, 1250-1276, which draws on Dongjing Meng Hua Lu, a nostalgic memoir of the city of Kaifeng. In 1049, the Youguosi Pagoda – or Iron Pagoda as it is called today – was constructed measuring 54.7 metres in height. It has survived the vicissitudes of war and floods to become the oldest landmark in this ancient city. Another Song-dynasty pagoda, Po Tower, dating from 974, has been destroyed. Another well-known sight was the astronomical clock tower of the engineer and statesman Su Song, it was crowned with a rotating armillary sphere, hydraulically-powered, yet it incorporated an escapement mechanism two hundred years before they were found in the clockworks of Europe and featured the first known endless power-transmitting chain drive.
Kaifeng reached its peak importance in the 11th century when it was a commercial and industrial center at the intersection of four major canals. During this time, the city was surrounded by three rings of city walls and had a population of between 600,000 and 700,000, it is believed that Kaifeng was the largest city in the world from 1013 to 1127. This period ended in 1127, it subsequently came under the rule of the Jurchen Jin dynasty, which had conquered most of North China during the Jin–Song Wars. While it remained an important administrative center, only the city area inside the inner city wall of the early Song remained settled and the two outer rings were abandoned. One major problem associated with Kaifeng as the imperial capital of the Song was its location. While it was conveniently situated along the Grand Canal for logistic supply, Kaifeng was militarily vulnerable due to its position on the floodplains of the Yellow River. Kaifeng was reconstructed during this time; the Jurchen kept their main capital further north until 1214 when they were forced to move the imperial court southwards to Kaifeng in order to flee from the onslaught of the Mongols.
In 1232 they succumbed to the combined Song forces in the Mongol siege of Kaifeng. The Mongols captured the city, in 1279 they conquered all of China. At the beginning of the Ming dynasty in 1368, Kaifeng was made the capital of Henan province. In 1642, Kaifeng was flooded by the Ming army with water from the Yellow River to prevent the peasant rebel Li Zicheng from taking over. After this disaster, the city was abandoned again. In 1662, during the reign of the Kangxi Emperor in the Qing dynasty, Kaifeng was rebuilt. However, further flooding occurred in 1841 followed by another reconstruction in 1843, which produced the contemporary Kaifeng as it stands today. On 6 June 1938, the city was occupied by the invading Japanese Imperial Army. Kaifeng is also