Clockworkrefers to the inner workings of either mechanical devices calledclocksandwatches(where it is also called themovement) or other mechanisms that work similarly, using a series ofgearsdriven by a spring or weight.[1][2][3]
A clockwork mechanism is often powered by a clockwork motor[4]consisting of amainspring,a spiraltorsion springof metal ribbon. Energy is stored in the mainspring manually bywinding it up,turning a key attached to aratchetwhich twists the mainspring tighter. Then the force of the mainspring turns the clockwork gears, until the stored energy is used up. The adjectiveswind-upandspring-poweredrefer to mainspring-powered clockwork devices, which include clocks and watches, kitchentimers,music boxes,andwind-up toys.
History
editThe earliest known example of a clockwork set-up is theAntikythera mechanism.This device functioned as a gearedanalogue computerafter its creation during the first-century BCE timeframe, being somewhatastrolabe-like, and had gotten designed for calculatingastronomical positionsand particularly listingeclipses.Recovered from aGreekshipwrecka long while after its creation, its nature was a mystery after its initial rediscovery due to various points of damage. There are many other accounts of clockwork devices inAncient Greece,even in itsmythology,and said mechanism itself is sophisticated enough to indicate a significant history of lesser devices leading up to its creation.[5]
At some point, this level of sophistication in clockwork technology was lost or forgotten in Europe, and only returned when brought from theIslamicworld after theCrusades,along with other knowledge leading to theRenaissance.Clockwork finally recovered the equivalent of pre-Roman technological levels in the 14th century.[6]
As in Greek mythology, there are ambitious automation claims in the legends of other cultures. For example, inJewish legend,Solomonused his wisdom to design athronewith mechanical animals which hailed him as king when he ascended it; upon sitting down an eagle would place a crown upon his head, and a dove would bring him aTorahscroll. It's also said that whenKing Solomonstepped upon the throne, a mechanism was set in motion. As soon as he stepped upon the first step, a golden ox and a golden lion each stretched out one foot to support him and help him rise to the next step. On each side, the animals helped the King up until he was comfortably seated upon his throne.[7]
Inancient China,a curious account of automation is found in theLie Zitext, written in the 3rd century BC. Within it, there is a description of a much earlier encounter betweenKing Mu of Zhou(1023-957 BC) and a mechanical engineer known as Yan Shi, an 'artificer'. The latter proudly presented the king with a life-size, human-shaped figure of his mechanical handiwork (Wade-Gilesspelling):
The king stared at the figure in astonishment. It walked with rapid strides, moving its head up and down, so that anyone would have taken it for a live human being. The artificer touched its chin, and it began singing, perfectly in tune. He touched its hand, and it began posturing, keeping perfect time...As the performance was drawing to an end, the robot winked its eye and made advances to the ladies in attendance, whereupon the king became incensed and would have had Yen Shih [Yan Shi] executed on the spot had not the latter, in mortal fear, instantly taken the robot to pieces to let him see what it really was. And, indeed, it turned out to be only a construction of leather, wood, glue and lacquer, variously coloured white, black, red and blue. Examining it closely, the king found all the internal organs complete—liver, gall, heart, lungs, spleen, kidneys, stomach and intestines; and over these again, muscles, bones and limbs with their joints, skin, teeth and hair, all of them artificial...The king tried the effect of taking away the heart, and found that the mouth could no longer speak; he took away the liver and the eyes could no longer see; he took away the kidneys and the legs lost their power of locomotion. The king was delighted.[8]
Other notable examples includeArchytas's dove, mentioned byAulus Gellius.[9]Similar Chinese accounts of flying automata are written of the 5th century BCMohistphilosopherMoziand his contemporaryLu Ban,who made artificial wooden birds (ma yuan) that could successfully fly, according to theHan Fei Ziand other texts.[10]
By the 11th century, clockwork was used for both timepieces and to track astronomical events, in Europe. The clocks did not keep time very accurately by modern standards, but the astronomical devices were carefully used to predict the positions of planets and other movement. The same timeline seems to apply in Europe, where mechanical escapements were used in clocks by that time.
Up to the 15th century, clockwork was driven by water, weights, or other roundabout, relatively primitive means, but in 1430 a clock was presented toPhilip the Good,Duke ofBurgundy,that was driven by a spring. This became a standard technology along with weight-driven movements. In the mid-16th century,Christiaan Huygenstook an idea fromGalileo Galileiand developed it into the first modernpendulummechanism. However, whereas the spring or the weight provided the motive power, the pendulum merely controlled the rate of release of that power via some escape mechanism (an escapement) at a regulated rate.
TheSmithsonian Institutionhas in its collection a clockwork monk, about 15 in (380 mm) high, possibly dating as early as 1560. The monk is driven by a key-wound spring and walks the path of a square, striking his chest with his right arm, while raising and lowering a small wooden cross and rosary in his left hand, turning and nodding his head, rolling his eyes, and mouthing silent obsequies. From time to time, he brings the cross to his lips and kisses it. It is believed that the monk was manufactured byJuanelo Turriano,mechanician to theHoly Roman EmperorCharles V.[11]
Overview
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Often power for the device is stored within it, via a winding device that applies mechanical stress to an energy-storage mechanism such as amainspring,thus involving some form ofescapement;in other cases, hand power may be utilized. The use of wheels, whether linked byfrictionorgearteeth, to redirect motion or gain speed ortorque,is typical; many clockwork mechanisms have been constructed primarily to serve as visible or implicittours de forceof mechanical ingenuity in this area. Sometimes clocks and timing mechanisms are used to set off explosives, timers, alarms and many other devices.
Examples
editThe most common examples are mechanicalclocksand watches. Other uses, most but not all obsolete, include:
- Wind-up toys– often as a simple mechanical motor, or to createautomata.These may be either key-wound, as were many 20th-centurymodel trains,or a simplerpullback motor.
- Most photographiccameraleaf shuttersuse a clockwork mechanism not unlike that of wristwatches to time the opening and closing of the shutter blades.
- Mechanisms to turn the lens oflighthousesbefore electric motors.
- Mechanical calculators,used before smallelectronic calculatorsbecame available in the 1970s. Relatively small calculators were used, for example, for companies' financial calculations.
- Mechanical computers,much more complex and larger than mechanical calculators, such asBabbage'sdifferenceandanalytical engines.
- Astronomical models, such asorrerieswhose history spans hundreds of years.
- Music boxes,which were very popular during the 19th century and at the beginning of the 20th.
- Almost all musical record-playingphonographs(gramophones) built before the 1930s.
- Hand-powered electrical equipment, such as aclockwork radio,where an energy-storing spring accounting for much of the size and weight of the device rotates a much smaller electricgenerator;such equipment is very popular wherebatteriesand mains power (house current) are scarce.
See also
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References
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- ^"Clockwork - Definition of clockwork by Merriam-Webster".merriam-webster.Archivedfrom the original on 2013-11-22.Retrieved2008-03-06.
- ^"Clockwork - Define Clockwork at Dictionary".Dictionary.Archivedfrom the original on 2013-11-25.Retrieved2008-03-06.
- ^"clockwork".Oxford English Dictionary(Online ed.).Oxford University Press.(Subscription orparticipating institution membershiprequired.)
- ^The Talking Machine Encyclopædia: A Comprehensive and Descriptive Glossary of All Terms Used in Connection with the Talking Machine.London: Phono Trader Printing and Publishing Co. 1908. pp. 45–47.Archivedfrom the original on 2023-07-03.Retrieved2021-11-09.,description of the clockwork motor in an antique phonograph
- ^Freeth, Tony (December 2009)."Decoding an Ancient Computer"(PDF).Scientific American.301(6): 78.Bibcode:2009SciAm.301f..76F.doi:10.1038/scientificamerican1209-76.PMID20058643.Archived(PDF)from the original on 2022-10-09.Retrieved26 November2014.
- ^The Role of Automata in the History of Technology
There appears to be no longer any question, on the basis of recent research, that the mechanical clock and fine instrumentation evolved in a direct line without substantial change from the mechanical water clocks of the Alexandrine civilization, transmitted through Islam and Byzantium from a tradition that may have originated in China, that reached Europe in the twelfth and thirteenth centuries.
- ^Mindel, Nissan."King Solomon's Throne".chabad.org.Archivedfrom the original on 2015-03-21.Retrieved2015-03-11.
- ^Needham, Volume 2, 53.
- ^Noct. Att. L.10
- ^Needham, Volume 2, 54.
- ^King, Elizabeth. "Clockwork Prayer: A Sixteenth-Century Mechanical MonkArchived2006-10-10 at theWayback Machine"Blackbird1.1 (2002)