Introduction
A clock is perhaps one of the oldest human developments in engineering. The name clock is coined from two Latin sounds- clocca and clagan, which denote a bell. In the early ages, a silent piece for alerting people on time was known as a timepiece (Itano & Norman, 1999, p.56). In the modern usage, a clock refers to any instrument that can be deployed to measure coupled with displaying time.
Watches are version of clocks, which can be carried by an individual. Since time immemorial of the evolution of clock, the main purpose, irrespective of accuracy and preciseness of a clock version, is to determine time in lesser units relative to the accepted units of time such as a “calendar day, a lunar month, and or a year” (Itano & Norman, 1999, p.56).
Over the process of evolution in the engineering of a clock, several mechanisms have been invented and deployed in the construction of an actual clock, which has often been used in cities and within people’s dwellings since the middle ages. Indeed, “devices operating on several physical processes have been used over the millennia culminating into the modern version of clocks” (Jones, 2004, p.67).
These modern versions of clocks are mainly mechanical clocks having either analogue or digital display formats. One of the earliest clocks was the sundials whose operation relied on the natural phenomena of different sizes of shadows cast on an object as times progress in a day.
New engineering discoveries led to the emergence of new versions of clocks such as water clocks, candle clocks, pendulum clocks, incense clocks, and later clocks with escapements and gears followed by the most accurate clocks – atomic clocks. The purpose of this paper is to scrutinize the historic evolution of a clock.
The theoretical approaches deployed in the paper are from engineering paradigms. In this light, the paper tracks changes in the operation mechanisms of the clock in the quest to provide theoretical records of evolution of engineering.
How the Clock developed over Early Years (1-1500 AD) in terms of Engineering
Sundial Clocks
Sundial clocks were deployed to measure times through a shadow cast on a cylindrical stone. This clock was widely used during ancient times since it would measure time with high degrees of accuracy. However, the time measured by the instruments was merely the solar time.
The sundials were deployed to scrutinize the operation of the clocks until early in the recent times. Engineering designs deserve to be reliable over a wide range of variables. This requirement posed major challenges to the development of a more reliable clock sun was required to shine since for its operation.
Consequently, the clock could not function at night or during cloudy weather conditions. Seasons change. Hence, recalibration of the clock was necessary whenever such changes occurred. These limitations made provisions for the need to develop other techniques of times measuring in a more reliable manner. Such a technique was the development of candle clock.
Candle Clocks
There exists a historic timeline gap for when the candle clocks were discovered and or used first. Nevertheless, they were first mentioned in You Jinful poem written in Chinese language in 520. With regard to the poet, a calibrated candle was deployed to help people determine the time at night. A corresponding class of “candles were later to be used in Japan until early 10th century” (Itano & Norman, 1999).
The most famous candle clock is related to King Alfred the great. From an engineering perspective, the clock was made from six candles, which were composed of 72 pennyweights derived from wax. Each candle was 12 inches long calibrated at an interval of 1 inch. Another important requirement for candles used to make the clock was that they were all required to be of uniform thickness.
The candles were consumed for close to four hours with each mark representing a 20-minute time erasure. One of the challenges of the clock was that the candles could be extinguished once they were lit hence impairing the performance of the clock. However, this issue was later to be less of a challenge since “the candles were placed in wooden framed glass, to prevent the flame from extinguishing” (Itano & Norman, 1999, 41). As time progressed, the design of the candle clocks became even more sophisticated.
In 1206, Al-Jazari’s work had one of the exceptionally complicated candle timers. With regard to Lankford and Taylor (1999), one of his candle clocks “included a dial to display the time and, for the first time, employed a bayonet fitting, a fastening mechanism still used in the modern times” (p.131).
The rate of burning of the candle used for making the clock needed to have a rate of a known burning. A wick was fitted inside a hole passing through the candles’ center. An indentation was also provided to aid in the collection of the wax melted out as a strategy to help in the prevention of likelihoods of interference with the rates of burning of the candle.
Lankford and Taylor (1999) further add that the candle clock described by Al-Jazari had “the bottom of the candle rested in a shallow dish that had a ring on its side connected through pulleys to a counterweight” (p.132). As the candle progressed to glow, it was pressed up by the load at a steady pace.
As Rossum (1996) reveals, “the automata were operated from the dish at the bottom of the candle” (p.65). In fact, in the early ages, no other candle clock was discovered having this intensity of sophistication. The only variation was the oil lamp clocks. The oil-lamp clocks were made up of a reservoir to hold the oil. The oil was mainly derived from the whale. It was the most appropriate since it burnt cleanly and evenly.
The tank was then calibrated so that, as the its oil level fell, it was possible to have an approximate quantity of the time that had elapsed. Clocks made this way presented major challenges because resetting was necessary whenever the candles were totally consumed or the oil-lamp became empty.
Incense Clocks
Incense clocks were a major achievement in the development of clock since incense clocks were easily adaptable for interior application partly because the gadgets produced light in a constant manner and without fire unlike the candle timers. This condition made them more reliable since they were more accurate than the candle clocks. Although the use of incense candles has been identified by historians in Japan, there are speculations that the first incense clock could have been discovered in India.
In the 6th century, the clocks had paved their way into China. Many variations of these gadgets were used with the most common ones being the “incense seal and incense stick” (Lankford & Taylor, 1999, p.49). Although the incense wooden timer was principally made up of a marked incense wood, others were sophisticated by adding loads by means of strings at the wooden pieces.
As the incense burnt out, these weights fell on a gong, which produced a sound while hit to indicate the amount of time that had elapsed. In addition, “some incense clocks were held in elegant trays…open-bottomed trays were also used, to allow the weights to be used together with the decorative tray” (Lankford & Taylor, 1999, p.50).
An alternative way of alerting people that a certain amount of time had elapsed was the deployment of incense sticks with different fragrance. Incense wooden pieces were either straight or spiraled depending on the amount of time each was anticipated to last with the spiral one taking more time. The spiraled incense stick clocks were mainly suspended from ceilings in houses and or religious places.
Incense seal clocks had similar application to the incense stick clocks. The only exemption was that these types of incense clocks were principally meant for religious functions (Rossum, 1996). The clocks were also significantly common in social gatherings. They were also highly associated with Chinese intellectuals and scholars.
Essentially, a seal was made up of “a wooden or stone disk with one or more grooves attached to it and incense placed in it“ (Rossum, 1996, p.148). Although incense clocks had garnered many customers in China, they were also made in Japan though not as many as in China.
In the effort to alert people that a certain length of time had elapsed, resins and various types of aromatic sticks and or incenses with a variety of smells were securely placed in the powdered lines of the incense seal clock. For instance, the earliest seal clocks were constructed from stone or wood.
The Chinese people introduced metallic disks for use in making the clock. This invention occurred during the Song dynasty. This evolution provided an opportunity for artisans charged with the roles of making seal clocks an opportunity not only to make aesthetic seals but also larger ones. The use of metallic disks also permitted the designers to incorporate grooves and paths that varied to give a room for variations in the length of days in a year.
Water Clocks
Water clocks, alternatively called clepsydrae, coupled with the sundials are amongst the oldest clocks in the history of humankind. Due to their antiquity, Jones (2004) argues, “where and when they first existed are not known and perhaps unknowable” (p.33). However, people believe that some types of water clocks had been used in Babylon and Egypt in the 16th century.
These versions were mainly bowl-shaped outflow water clocks. It is also important to note that some other parts of the world including China and India had some evidence of having used water clocks. However, the precise date when this case occurred remains a nightmare because there have been arguments around this topic with some authors claiming that water clocks were used in China and India in 4000 BC (Jones, 2004).
Amid the historical debate around the subject of when water clocks first appeared in human civilizations of engineering endeavors, a substantive contentment among historians holds that, from 27 AD to 500 AD, Roman astronomers coupled with horologists engaged in the development of elaborate water clocks that were mechanized.
In the words of Rossum (1996), the main aim of engineering complicated water clocks was “to regulate the flow at providing fancier displays of the passage of time” (p.77). Astrological systems of the earth were even demonstrated by some types of water watch machines.
Muslims experts invented the most sophisticated water clocks. In particular, a design that was more fascinating was the elephant clock made by Al-Jazari in the middle ages. “The clock recorded the passage of temporal hours, which meant that the rate of flow had to be changed daily to match the uneven length of days throughout the year” (Rossum, 1996, p.57).To realize this endeavor, the clock design had two tanks.
To serve their work well, as Rossum (1996, p.57) points out, “The bottom tank was linked to flow the control regulator while the top tank was linked to the mechanisms that indicated time”. At sunrise, a faucet released a stream to run into the underneath reservoir under the check of a hang controller that was meant to ensure that a steady weight was assured at the receiving reservoir.
How the Clock Developed after 15th Century to the Mechanical Clocks
The design approaches and engineering technology levels in the early ages to Middle Ages did not give a room for designers to construct clocks with the hour, minute, and second means of measuring time. They only measured time in terms of hours. In fact, as Landes (2000, p. 43) reveals, “a clock that had minute dials first appeared in 1475 with clocks having both minutes and second dial appearing by 15th century in Germany”.
However, developments in the clock were still limited until when the massive mechanisms of improving accuracy of the clocks were developed. The mechanisms included the pendulum system and spiral springs. One of the historic events in the use of accurate clocks via both minutes and seconds dial was realized when Tycho Brahe (an astronomer) used such a clock to observe various stellar positions in the 16th century.
Pendulum Clocks
The development of mechanical clocks leads to miniaturization of the clocks. By the end of the 15th century, clocks such as the Al-Jazari elephant clock were considered as past tense so that smaller clocks could be made for domestic applications coupled with usages as personal watches by16th century.
This development was preceded by discoveries made by Polymath Galileo, an Italian Engineer. He revealed that the oscillations of a pendulum could indeed be deployed to operate and or control a timer. However, he never constructed a clock based on the principles of pendulum.
Christian Huygens, a Dutch scientist, would design a clock based on the concepts of pendulum investigated by the Polymath Galileo in 1656. Many versions of clocks based on the pendulum principles were later designed. The earliest designs produced errors in time measurement in the ranges of less than a minute within a day. The most accurate ones had errors of less than 10 seconds within a day. This realization was perhaps the best accuracy levels in time measurement during the 16th century.
In the 17th and 18th century, clock developments were mainly based on the precision and improved accuracy requirements. In this regard, Jesuits were incredibly instrumental. To emphasize on this point, Landes (2000) asserts, “in measuring an accurate one-second pendulum, for example, the Italian astronomer Father Giovanni Battista persuaded nine fellow Jesuits to count nearly 87,000 oscillations in a single day” (p.97).
Consequently, they played significant roles in the development of the pendulum clock since they participated in testing and spreading engineering ideas of time. Modern clocks such as long case clock have their origin anchored in the invention of engineering discoveries such as anchor escapement. This clock operation mechanism was discovered in the 1670s. Before the discovery of the mechanism, pendulum clocks principally depended on the verge escapement mechanism for their operations.
Verge escapement mechanisms needed an extremely large pendulum dangle in the range of 100 degrees. The anchor mechanisms served to reduce this swing to values of about four to six degrees. This reduction not only gave pendulum clock makers an opportunity to make clocks having longer pendulums but also clocks with slowed beats.
The overall effect was the reduction of the amount of power required to operate the clock following the reduction in friction. Apart from the reduction of wear in this generation of pendulum clocks, they also emerged as more accurate in comparison to those, which predeceased them.
These developments paved way for the creation of businesses, which principally aimed at manufacturing mechanical of clocks. Now, it is crucial to consider a discussion of clock makers before proceeding to discussion of evolution of other types of mechanical clocks.
Clock Makers and Evolution of Mechanical Watches and Clocks
Locksmith and jewelries were the first professional clock makers in the history of clock making. With regard to American Society of Mechanical Engineers, as years progressed, the craft and science (engineering) of clock making advanced from pure custom to mass production (2002, p.31).
In Paris, France, coupled with Blois were the main centers for making clocks for mass consumptions. Julien Le Roy and Versailles led the market in the design and production of ornamental and case-designed clocks. As Lankford and Taylor (1999) posit, “Le Roy belonged to the fifth generation of a family of clockmakers, and was described by his contemporaries as the most skillful clockmaker in France, possibly in Europe” (p.129).
Le Roy also invented a repeating mechanism, which made it possible to improve the accuracy and precision of the clock to higher levels than those recorded for the pendulum clock.
The clocks and watches that were designed by Le Roy also had a face that could be opened up to view the engineering behind the clock. The clock maker also supervised the process of making about 3,500 watches. Consequently, an intense scientific competition emerged with many researchers focusing on looking for other alternative ways of measuring time in ways that are more accurate.
In 1794, following the French revolution, the government of France mandated brief production of decimal clocks. These clocks had a day divided into 10 hours with each hour having 100 minutes. Through the effort of engineering modifications of Pierre Simon Laplace, pocket watch was modified into decimal form.
Although this technology was extended to many other watches apart from the Pierre Simon Laplace’s until 1801, conversion of all watches within France into a decimal form was impossible due to the high costs associated with the process. The decimal system was also not viable since it only served the astronomers implying that the system was not useful to the ordinary citizens. Thus, it was not considered any further in the early 1800s.
In the case of Germany, Augsburg and Nuremberg were there main clock makers. However, Black Forest specialized in the production of Cuckoo clock, which was wooden.
In the 17th and 18th century, the English people dominated the watch making industry. Indeed, at the dawn of the 19th century, William Paley deployed the equivalence of a watch making to argue that all things are planned meaning that they have their planners and hence the theoretical reasoning behind the discipline of Engineering.
Looking at the design of watches from this paradigm, there emerged research and subsequent construction of more accurate watches and clocks such as chronometers, atomic clocks, quartz oscillators, and wrist watches among others. Some of these clocks are discussed below.
Patek Philipe invented the wristwatch in 1868. His watch was mainly purposed to serve as a woman’s bracelet. At the dawn of the 20th century, Alberto Santos-Dumont requested his acquaintance who was in the clock making business to make for him a gadget (clock) that could assist him in times of flights since a pocket watch was not expedient. In response to this request, Louis created the first man’s wristwatch.
Later, military workforce were engaged in mass making of clocks for airplane controllers coupled with infantry. Such watches got immense popularity during the First World War though they remained a reserve for the middle class people.
During World War II, A-11 wristwatch became common among the US air force men. In Engineering perspective, the watch met Ego-metrics (the degree to which an engineering creation is usable by the targeted end user based on requirements for readability and usability) since it was calibrated with clear white numbers.
Another invention that shaped the clock evolution process was the quartz oscillators. These types of gadgets were highly inspired by the inventions of nano biosensor characteristics of materials. In 1932, these watches evolved to the levels of being able to gauge little differences in time due to the revolution of the earth.
Indeed, as Lankford and Taylor (1999, p. 129) point , “the NIST (national bureau of standards) used time standards based on the quartz clock as from 1929 to 1960”.
With the development of atomic clocks, which were more accurate than quartz clock, the organization shifted its time standards from being based on the quartz clock to atomic clocks. Atomic watches remain the most precise gadgets ever to be made. Their accuracy levels are in the range of a few seconds over a period of several thousand years. The first watch of this type was built in 1949.
Conclusion
Sundial and water clocks were the earliest clocks to be made. On the other extreme, the quartz watch and the atomic clocks form the most recent discoveries. As the paper unveiled, during the processes of evolution from the most primitive types of watches and clocks to the most modern ones, the main concern of this expert was to look for mechanisms of enhancing the accuracy and preciseness of the clocks and watches. This process occurred alongside improvements of the clock to serve the purpose of measuring times and esthetic purposes.
Reference List
American Society of Mechanical Engineers. (2002). Proceedings of the 2002 ASME Design Engineering Technical Conferences. London: American Society of Mechanical Engineers.
Itano, W., & Norman, F. (1999). Accurate Measurement of Time. Scientific American, 269 (1), 56–65.
Jones, T. (2004). Splitting the Second: The Story of Atomic Timekeeping. Bristol, UK: Institute of Physics Publishing.
Landes, D. (2000). Revolution in Time: Clocks and the Making of the Modern World. Cambridge: Harvard University Press.
Lankford, J., & Taylor, F. (1999). Time and timekeeping instruments. History of astronomy, 34(3), 127-158.
Rossum, G. (1996). History of the Hour: Clocks and Modern Temporal Orders. Chicago: University of Chicago Press.