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Comtoise Clock
A grandfather clock (also a longcase clock, tall-case clock, grandfather's clock, hall clock or floor clock) is a tall, freestanding, weight-driven pendulum clock, with the pendulum held inside the tower or waist of the case. Clocks of this style are commonly 1.8–2.4 metres (6–8 feet) tall with an enclosed pendulum and weights, suspended by either cables or chains, which have to be occasionally calibrated to keep the proper time. The case often features elaborately carved ornamentation on the hood (or bonnet), which surrounds and frames the dial, or clock face. The English clockmaker William Clement is credited with developing the form in 1670. Pendulum clocks were the world's most accurate timekeeping technology until the early 20th century. Further, longcase clocks, due to their superior accuracy, served as time standards for households and businesses. Today, they are kept mainly for their decorative and antique value, having been superseded by analog clock, analog and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grandfather Clock Ticking
Grandparents, individually known as grandmother and grandfather, or Grandma and Grandpa, are the parents of a person's father or mother – paternal or maternal. Every sexually reproducing living organism who is not a genetic chimera has a maximum of four genetic grandparents, eight genetic great-grandparents, sixteen genetic great-great-grandparents, thirty-two genetic great-great-great-grandparents, sixty-four genetic great-great-great-great-grandparents, etc. In the history of modern humanity, around 30,000 years ago, the number of modern humans who lived to be a grandparent increased. It is not known for certain what spurred this increase in longevity, but it is generally believed that a key consequence of three generations being alive together was the preservation of information which could otherwise have been lost; an example of this important information might have been where to find water in times of drought. In cases where parents are unwilling or unable to provide ade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Bicentennial
The United States Bicentennial was a series of celebrations and observances during the mid-1970s that paid tribute to historical events leading up to the creation of the United States as an independent republic. It was a central event in the memory of the American Revolution#Commemorations, American Revolution. The Bicentennial culminated on Sunday, July 4, 1976, with the 200th anniversary of the adoption of the United States Declaration of Independence, Declaration of Independence by the Founding Fathers of the United States, Founding Fathers in the Second Continental Congress. Background The nation had always commemorated the founding as a gesture of patriotism and sometimes as an argument in political battles. Historian Jonathan Crider points out that in the 1850s, editors and orators both North and South claimed their region was the true custodian of the legacy of 1776, as they used the Revolution symbolically in their rhetoric. The plans for the Bicentennial began when 89th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tallest Grandfather Clock
The World's Tallest Grandfather Clock is a roadside attraction in downtown Kewaunee, Wisconsin. It is a 36-foot-tall Colonial-style redwood grandfather clock A grandfather clock (also a longcase clock, tall-case clock, grandfather's clock, hall clock or floor clock) is a tall, freestanding, weight-driven pendulum clock, with the pendulum held inside the tower or waist of the case. Clocks of this styl ... built in 1976. It is located at the Ahnapee State Trail trailhead. References Tourist attractions in Kewaunee County, Wisconsin Clock towers in Wisconsin 1976 establishments in Wisconsin Towers completed in 1976 {{Wisconsin-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pullchain
A pullstring (pull string, pull-string), pullcord (pull cord, pull-cord), or pullchain (pull-chain, pull chain) is a string, cord, or chain wound on a spring-loaded spindle that engages a mechanism when it is pulled. It is most commonly used in toys and motorized equipment. More generally and commonly, a pullstring can be any type of string, cord, rope, or chain, attached to an object in some way used to pull or mechanically manipulate part of it. Toys Perhaps the simplest pullstring toy is the yo-yo (c. 460 BCE). The jumping jack is a more complicated animated puppet paper doll that uses a pullstring to move its arms and legs up and down. Trompos and some spinning tops use a string that is wound around the top and then pulled to make it spin. More recent toys include dolls, such as Chatty Cathy (1959), Charmin' Chatty (1963), Talking Tamu (1970), Look Around Crissy (1972), Sky Dancers (1994), and Sheriff Woody (from the ''Toy Story'' franchise), that have a pullstring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for this is the ''law of the lever.'' Machine components designed to manage forces and movement in this way are called mechanisms. An ideal mechanism transmits power without adding to or subtracting from it. This means the ideal machine does not include a power source, is frictionless, and is constructed from rigid bodies that do not deflect or wear. The performance of a real system relative to this ideal is expressed in terms of efficiency factors that take into account departures from the ideal. Levers The lever is a movable bar that pivots on a fulcrum attached to or positioned on or across a fixed point. The lever operates by applying forces at different distances from the fulcrum, or pivot. The location of the fulcrum deter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulley
Sheave without a rope A pulley is a wheel on an axle or shaft enabling a taut cable or belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. A pulley may have a groove or grooves between flanges around its circumference to locate the cable or belt. The drive element of a pulley system can be a rope, cable, belt, or chain. History The earliest evidence of pulleys dates back to Ancient Egypt in the Twelfth Dynasty (1991–1802 BC) and Mesopotamia in the early 2nd millennium BC. In Roman Egypt, Hero of Alexandria (c. 10–70 AD) identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt and chain drives in order to transmit power from one rotating shaft to another. Plutarch's ''Parallel Lives'' recounts a scene where Archimedes proved the effectiveness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Striking Clock
A striking clock is a clock that sounds the hours audibly on a bell, gong, or other audible device. In 12-hour striking, used most commonly in striking clocks today, the clock strikes once at 1:00 am, twice at 2:00 am, continuing in this way up to twelve times at 12:00 mid-day, then starts again, striking once at 1:00 pm, twice at 2:00 pm, and the pattern continues up to twelve times at 12:00 midnight. The striking feature of clocks was originally more important than their clock faces; the earliest clocks struck the hours, but had no dials to enable the time to be read. The development of mechanical clocks in 12th century Europe was motivated by the need to ring bells upon the canonical hours to call the community to prayer. The earliest known mechanical clocks were large striking clocks installed in towers in monasteries or public squares, so that their bells could be heard far away. Though an early striking clock in Syria was a 12-hour clock, many early clocks struck up to 24 st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Movement (clockwork)
In horology, a movement, also known as a caliber or calibre (British English), is the mechanism of a watch or Clock, timepiece, as opposed to the ''case'', which encloses and protects the movement, and the ''clock face, face'', which displays the time. The term originated with mechanical timepieces, whose clockwork movements are made of many moving parts. The movement of a digital watch is more commonly known as a module. In modern mass-produced clocks and watches, the same movement is often inserted into many different styles of case. When buying a quality pocketwatch from the mid-19th to the mid-20th century, for example, the customer would select a movement and case individually. Mechanical movements get dirty and the lubricants dry up, so they must periodically be disassembled, cleaned, and lubricated. One source recommends servicing intervals of: 3–5 years for watches, 15–20 years for grandfather clocks, 10–15 years for wall or mantel clocks, 15–20 years for anniv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grandfather Clock Q
Grandparents, individually known as grandmother and grandfather, or Grandma and Grandpa, are the parents of a person's father or mother – paternal or maternal. Every sexually reproducing living organism who is not a genetic chimera has a maximum of four genetic grandparents, eight genetic great-grandparents, sixteen genetic great-great-grandparents, thirty-two genetic great-great-great-grandparents, sixty-four genetic great-great-great-great-grandparents, etc. In the history of modern humanity, around 30,000 years ago, the number of modern humans who lived to be a grandparent increased. It is not known for certain what spurred this increase in longevity, but it is generally believed that a key consequence of three generations being alive together was the preservation of information which could otherwise have been lost; an example of this important information might have been where to find water in times of drought. In cases where parents are unwilling or unable to provide ade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deadbeat Escapement
In horology, the anchor escapement is a type of escapement used in pendulum clocks. The escapement is a mechanism in a mechanical clock that maintains the swing of the pendulum by giving it a small push each swing, and allows the clock's wheels to advance a fixed amount with each swing, moving the clock's hands forward. The anchor escapement was so named because one of its principal parts is shaped vaguely like a ship's anchor. The anchor escapement was invented by clockmaker William Clement, who popularized the anchor in his invention of the longcase or grandfather clock around 1680. Clement's invention was a substantial improvement on Robert Hooke's constant force escapement of 1671. The oldest known anchor clock is Wadham College Clock, a tower clock built at Wadham College, Oxford, in 1670, probably by clockmaker Joseph Knibb. The anchor became the standard escapement used in almost all pendulum clocks. A more accurate variation without recoil called the deadbeat escap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minute Hand
A clock face is the part of an analog clock (or watch) that displays time through the use of a flat dial with reference marks, and revolving pointers turning on concentric shafts at the center, called hands. In its most basic, globally recognized form, the periphery of the dial is numbered 1 through 12 indicating the hours in a 12-hour cycle, and a short hour hand makes two revolutions in a day. A long minute hand makes one revolution every hour. The face may also include a ''second hand'', which makes one revolution per minute. The term is less commonly used for the time display on digital clocks and watches. A second type of clock face is the 24-hour analog dial, widely used in military and other organizations that use 24-hour time. This is similar to the 12-hour dial above, except it has hours numbered 1–24 (or 0–23) around the outside, and the hour hand makes only one revolution per day. Some special-purpose clocks, such as timers and sporting event clocks, are des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
