Talk:History of timekeeping devices

Numerous errors and omissions
Under "Shadow clocks and sundials" is stated that "In Egyptian obelisks, constructed c. 3500 BC, are among the earliest shadow clocks." which is cited to be from Encyclopedia Britannica, which makes no such claims -- EB writes "The first device for indicating the time of day was probably the gnomon, dating from about 3500 bce. It consisted of a vertical stick or pillar, and the length of the shadow it cast gave an indication of the time of day." What is worse, according to obelisk the earliest known obelisk is from the rule of Senusret 1 who ruled from 1971 BC to 1926 BC or from 1920 BC to 1875 BC. — Preceding unsigned comment added by Gleb713 (talk • contribs) 17:28, 2 January 2023 (UTC)

Just at a cursory glance, this article has numerous factual errors and omissions of important points; it should probably be removed from Featured Article status until these are corrected.
 * "Water clocks, or clepsydrae, were commonly used in Ancient Greece following their introduction by Plato..." Anaxagorus and Empedocles mention clepsydrae, long before Plato  1.
 * I'll amend the text, as Plato's supposed alarm clock was made long after the first use of water clocks in Greece, as you say. Amitchell125 (talk) 15:18, 7 May 2021 (UTC)


 * The section on "Mechanical clocks" combines and conflates water clocks and all-mechanical verge and foliot clocks, and sluffs over the most important advance in timekeeping technology in 1000 years, the invention of the verge escapement in the late 13th century, which enabled the change in timekeeping technology from continuous to oscillatory processes, used in all modern clocks.  All clocks in this section prior to the late 1200s (besides Gregory's) were liquid clocks.
 * Onto it, . Amitchell125 (talk) 16:41, 10 May 2021 (UTC)
 * The article has been restructured to tak the above comment into account—although the work to be done is not completed, the developments in the late 13th century can now be discussed separately from continuous flow clocks such as the clepsydra. Amitchell125 (talk) 18:18, 1 June 2021 (UTC)


 * "Clock towers in Western Europe in the Middle Ages were also sometimes striking clocks." Early tower clocks were always striking clocks, that's why they were put in towers, so they could be heard at a distance.
 * Agreed, sorted. Amitchell125 (talk) 06:25, 23 May 2021 (UTC)


 * "The longcase clock (also known as the grandfather clock) was first created to house the pendulum and works by the English clockmaker William Clement in 1670 or 1671; this became feasible after Clement invented the anchor escapement mechanism in about 1670." Although some sources credit Clement, most agree Robert Hooke invented the anchor in 1658 2, 3, 4.   Clement didn't sell longcase clocks until 1680.
 * Sorted. Amitchell125 (talk) 15:04, 3 June 2021 (UTC)


 * "To avoid the need for a very large case, most clocks using the verge escapement had a short pendulum."  That was only freestanding clocks, plenty of wall-mounted verge clocks had long pendulums.  They were called "Wag-on-the-wall" clocks.
 * Now gone. Amitchell125 (talk) 06:27, 23 May 2021 (UTC)


 * The "Pendulum clock" and "Pocketwatch" sections don't mention why the pendulum and sprung balance wheel improved accuracy so much; they were the first harmonic oscillators applied to timekeeping. This was the second most important advance in timekeeping in 1000 years, and the article totally misses it.  All modern clocks use harmonic oscillators.
 * Temperature-compensated pendulums are not mentioned. These enabled the construction of regulator clocks accurate enough to be used for celestial navigation, and to meet the demands of the Industrial Revolution.
 * Done. Amitchell125 (talk) 08:40, 6 August 2021 (UTC)


 * The "Equation clock" section doesn't clearly state the reason for this complication; it was not to "...[satisfy] the demand for clocks that always agreed with sundials" but to facilitate setting the clock by celestial observations of the sun or stars, which was the only way to set a clock before accurate time standards.
 * , I can't find a citation to verify this last one, can you help? Amitchell125 (talk) 15:59, 4 June 2021 (UTC)
 * Well, although I'm sure I read it somewhere, I can't find a source that states specifically that. However it is clear from context in Desbourough, Reid, p.294-295, 313,  Beckett, p.145-147,  Milham, p.211-212.  Prior to the late 1800s when time began to be distributed by telegraph lines, the only way for a person living outside a city to set their clock was by the sun or stars.  Before railroads instituted time zones, clocks were set to "mean solar time", roughly the time that would be shown by the sun if all days were the same length, which varied from solar time by up to ±16 minutes during the year.  People used a sundial or transit to determine solar noon, the moment the sun was overhead, then looked in an almanac table called "Equation of time" which gave how many minutes the clock should be set ahead or behind the sun on that date.  The "equation of time dial" was a rare complication on expensive clocks that allowed the owner to skip the step of looking in an almanac, it gave the correction to set the clock to mean solar time. --ChetvornoTALK 02:46, 5 June 2021 (UTC)
 * Thanks for pointing me in the right direction. Amitchell125 (talk) 12:26, 12 June 2021 (UTC)


 * "Later equation clocks, although accurate, were very expensive, and the use of equation clocks declined as it became clear that the position of the sun was too inaccurate a way to keep time properly." Misleading; the issue was not just accuracy per se, but synchronism ([Milham, p.15-18). "Mean solar time", which is what the "equation of time" gave, was a local time, it was based on sun position (longitude) and so varied in each village.  "Mean solar time" gave way to "[[standard time]]" which was based on time zones, during the late 1800s when railroads were built.  It became important to have all clocks in a large region agree with each other, so train schedules could be based on a single time standard, so people could catch trains on time, and so trains running on the same track would not collide.  Rural people set their clocks by a regulator clock in the local train station, which was kept accurate by time signals transmitted over telegraph wires.  Also "equation clocks" were never widely used (Desborough, p.174), equation of time dials were a vanity complication included in a few expensive clocks as a status symbol.  Most people used "Equation of time" tables in almanacs.  It is probably WP:undue weight to have an entire section of the article devoted to this minor feature. --ChetvornoTALK 05:01, 5 June 2021 (UTC)
 * -- Chetvorno TALK 04:16, 10 June 2014 (UTC)
 * Sorted (text reduced and placed with a different section. Amitchell125 (talk) 07:50, 12 June 2021 (UTC)


 * "Thomas Woods writes: (...) The first recorded clock was built by the future Pope Sylvester II for the German town of Magdeburg, around the year 996." What kind of clock? A clock or an astronomical instrument? Thietmar of Merseburg 6, 61: [Gerbertus] in Magadaburg orologium fecit, illud recte constituens, considerata per fistulam quadam stella nautarum duce ([Gebert] ... at Magdeburg ... built an orologium, positioning it correctly, after he had observed through a tube the star that sailors use for guidance). Pilot Pirx (talk) 19:11, 1 October 2020 (UTC)
 * Text removed, (following another comment about this sentence). Amitchell125 (talk) 07:28, 12 June 2021 (UTC)

In conjunction with Amitchell125's excellent work upgrading the article, I looked at the article again and noticed some things I think could be improved. These are just my opinions:
 * I like the division of the history into three main parts. It is consistent with a very authoritative outline of timekeeping history by the inventor of the quartz clock:  Warren Marrison (1948) The evolution of the quartz crystal clock, Bell System Tech. Jour., Vol.20, p.510.  I suggest including more about the historical technological breakthroughs that made each era an advance on the last.  Here are Marrison's three timekeeping eras:
 * Era of continuous timekeepers - This was all timekeeping devices up to the late 1200s. They measured time by some continuous process: the motion of celestial bodies in the sky, burning, flow of a liquid. I would suggest maybe a separate section on liquid clocks, instead of spreading them out in sections devoted to the different nations, since they were important as the first real 'clocks', and also the development of geared clockwork used in later clocks.
 * Era of oscillating timekeepers (mechanical clocks) - This started with the invention of the escapement in the late 1200s, which made all-mechanical clocks possible, which kept time with oscillation, a more accurate timekeeper than liquid flow. These first mechanical clocks (verge and foliot clocks) were relaxation oscillators, they didn't have a resonant frequency so they had very poor isochronism and their rate varied with unavoidable variations in drive force.  Maximum accuracy achieved was only about 15 min/day.
 * Era of harmonic oscillators - This began with the invention of the pendulum and addition of the hairspring to the balance wheel in 1658, which made the timekeeper in both clocks and watches harmonic oscillators. The harmonic oscillator is the basis of every modern clock, including atomic clocks.  It's advantage is the oscillator uses resonance to vibrate at a constant resonant frequency dependent only on its makeup and resists vibrating at any other frequency.  The precision of a harmonic oscillator as a timekeeper is given by a parameter called its Q_factor, and improvements in timekeeping since 1900 have been based on adopting higher Q_factor harmonic oscillators, such as quartz crystals and cesium atoms.
 * The article has, to all intents and purposes, been restructured to reflect the three eras described above. I'm now working on the second era, which is a little lacking. Amitchell125 (talk) 12:46, 28 June 2021 (UTC)
 * The emphasis on 'liquid-driven escapements' is WP:undue weight. A 'liquid driven escapement' is not an 'escapement' in the sense of a device which controls an oscillating timekeeper, a revolutionary invention. These two should be carefully distinguished.  "The escapement mechanism is known to have been used in ancient Greece. The Chinese used a mercury-powered escapement mechanism in their 10th century clocks" is misleading and should probably be deleted, and the section "Clocks with liquid-driven escapements" should probably be replaced with a section on liquid clocks in general.  A clock with a liquid driven escapement is no more accurate than an ordinary liquid clock.  Both measure time by the rate of liquid flowing through an orifice, which varies with the level of liquid in the source container, temperature, viscosity, etc.  Emphasis on liquid escapements began with Joseph Needham's 1954 Science and Civilization in China in which he proposed that the mechanical escapement originated in China with liquid escapements, but I haven't come across any sources which support this.
 * Sorted. Amitchell125 (talk) 07:01, 12 June 2021 (UTC)
 * The sentence: "The first recorded clock was built by the future Pope Sylvester II for the German town of Magdeburg, around the year 996." should not be in the "Mechanical clocks" section. There is no credible evidence that mechanical oscillator clocks existed before the late 1200s, all prior clocks should be assumed to be liquid clocks.  There is no evidence of Sylvester's clock.  And since liquid clocks were known in antiquity, it was not the "first recorded clock", so that quote should either be qualified or deleted.
 * Now removed. Amitchell125 (talk) 06:44, 12 June 2021 (UTC)
 * The etymology of clock from Latin clocca (bell) given in "Early timekeeping innovations" should include the whole backstory. Medieval Christians (as well as Moslems) were required to pray at specific times during the day.  The first tower clocks in the Middle Ages (these were geared water clocks) were striking clocks without faces which rang bells on the canonical hours, to call the community to prayer, this is the origin of the name clocca.   Monasteries adhered to rigid schedules, and the evidence is that striking clocks developed from small "alarm clocks" to wake the monk who rang the monastery's big bell.  Later larger versions were mounted in the tower to ring the bell directly. By the 1200s a tower clock was a prestige project, and a building boom ensued as European towns and villages competed to build them for civic pride.  This was the background to the invention of the verge escapement and mechanical clock in the late 1200s.
 * --ChetvornoTALK 01:58, 13 May 2021 (UTC)
 * Sorted. Amitchell125 (talk) 19:24, 8 June 2021 (UTC)


 * In the "Pendulum clocks" section the sentence: "...and the deadbeat escapement, invented by the English clockmaker George Graham in 1720" is a common error found in many sources ,. The deadbeat escapement was actually invented by Richard Towneley, and first used by Graham's mentor Thomas Tompion in the two precision regulators he made for the new Greenwich Observatory in 1676, , , as detailed in Anchor escapement --ChetvornoTALK 01:25, 23 May 2021 (UTC)
 * Now corrected. Amitchell125 (talk) 20:21, 29 May 2021 (UTC)


 * Thanks,, there's clearly a lot of work that needs to be done on the article, and as I come across the sections connected with your comments above, I'll reply to your comments. Amitchell125 (talk) 06:30, 23 May 2021 (UTC)


 * Thanks for all the work you are putting into this article, this kind of overview article is a lot of labor. It looks improved.  Frankly I don't know how it originally passed the FA audit.  Hope you don't mind my criticisms of the article; they are certainly not aimed at you.  I'm an engineer and I got interested in timepieces and have worked on a lot of the horology articles: Pendulum, Balance wheel, Escapement, Mainspring, History of watches, etc. Cheers --ChetvornoTALK 17:17, 25 May 2021 (UTC)
 * Thanks, I've a physics background and I'm interested in the history of science, so this article—which needs a great deal doing to it—is enjoyable for me to work. I'll get to your comments eventually! Amitchell125 (talk) 19:09, 25 May 2021 (UTC)

Ancient Egypt = the history of the Civil War?
Immediately under the heading "Ancient Egypt", it states "See also: History of the civil war", with a link to the article on the American Civil War. Nothing else under that heading has anything to do with the American Civil War, so I'm at a loss to understand why it's referenced there. Can anyone explain? Occam&#39;s Shaver (talk) 06:54, 11 April 2015 (UTC)

WP:ERA
Well, that's a little bizarre. Usually I sort issues out by looking for the earliest system but the article started out as a mess using both systems. The earlier discussions got buried in the archive but Here User:AndonicO, Grimhelm, and J-stan all supported and only Keilana and Edmund Patrick didn't (albeit Keilana was rather forceful in reverting other users to her preference);  here, same people, same deal; and here, Bibliomaniac15 and Zginder supported  and a consensus was reached. For what it's worth, I also support as Keilana and Edmund Patrick's arguments are completely off: it's not any less religious and not any less biased and just as based on (incorrect) computations of Jesus's conception/birth/lunar phase whichever form is used.

Since the consensus has been reached, though, kindly maintain it consistently and revert or adjust well-meaning editors who don't notice the article's house style. — Llywelyn II   08:42, 8 September 2015 (UTC)
 * it is important to keep consensus and I have always been happy with that. As a non believer of deities and totally prepared to accept my own responsibility for my own actions I have no problem with AD / BC, but as a museum professional who working with peoples whose calendar is not even in "my" 21st century, before common era or before christian era and common / christian era is time specific and acknowledges that it is an imposed time scale which has become the international norm. It is less religious as it does not in one version use the word christian. it is biased as through human development it has become the international recognised method of measuring time. It is I agree based on incorrect computations but that is what we have to live with. A simple link would solve the problem, and it is a shame that after a brief scan of the article at no point is BC wikilinked to BC which it should once as an encyclopedia and once linked to BCE. If in the UK you are learning about time and time measurement in Key Stage 2 you may have come across BC (one would hope so but still no way to learn what it actually stands for) and if like my sons they were taught using BCE well this article offers no help what so ever! Edmund Patrick – confer 10:06, 8 September 2015 (UTC)
 * I'm glad that you agree with one of the foundational principles of the encyclopedia you're reading and (hopefully) working on.


 * The rest of your paragraph doesn't seem to make any sense. If your children don't know one of the most common abbreviations in the English language, that's really on you. All the moreso if you're actually "a museum professional" who presumably shares his love of history with the other loves of his life.


 * I'm not saying I can't link the BC article. I think we should. I'm just saying ten edits in, someone will come along and whinge about and claim that it's somehow unhelpful to use hyperlinks on an encyclopedia whose sole reason for existence is their helpfulness. —  Llywelyn II   00:44, 7 March 2017 (UTC)


 * Being that I have used this article as an example for a RFC here is the link: User_talk:Edmund_Patrick, first discussion here: Bot_requests. Thanks Edmund Patrick – confer 10:29, 14 December 2015 (UTC)
 * Those links are dead and discussion of this article and changes to it should happen here on the article's talk page. — Llywelyn II   00:39, 7 March 2017 (UTC)
 * As they would be as not permalinks Edmund Patrick – confer 08:33, 8 March 2017 (UTC)

Update to the hourglass section
Although the history of the hourglass may not be precisely known, it doesn't seem to have been used in China before the mid 16th century, and as Needham said in Science and Civilization, an hourglass implies the use of glassblowing, since it would be difficult to get an "hourglass" shape in without it. Glassblowing was not commonly done by the Chinese, thereby implying an European origin for the hourglass, although Needham himself does not specifically state that, but he does reference a source, Wang Chen-To, which does state that Chinese obtained the hourglass from the Dutch or Portuguese. — Preceding unsigned comment added by 198.111.162.10 (talk) 20:54, 14 April 2019 (UTC)
 * The article has been edited to include this information. Amitchell125 (talk) 06:38, 12 June 2021 (UTC)

FA in need of review
While this older FA is an impressive effort, particularly if we consider that it was promoted way back in 2008, I think that there are a number of significant issues here that have to be addressed so it can meet the current FA criteria. For instance:


 * In this talk page, I see a number of threads commenting on the inaccuracy of the article, (Numerous errors and omissions, Update to the hourglass section, and others), that have not been addressed and makes one wonder if the article is being actively watched and maintained (also the 2-month-old banner asking for a merge with no response till date);
 * The lead is exceedingly long;
 * Long, and excessively detailed on topics not directly related to the article (e.g. a lot about clockmakers and not how they made notable innovations). Working on cutting down the length of the article. Amitchell125 (talk) 06:29, 12 June 2021 (UTC)


 * There are several unsourced sentences in the text, and some subsections are completely unsourced (Clock towers, Equation clock);
 * Agreed, I'm slowing weeding out the incorrect citations, and adding citations where needed. Amitchell125 (talk) 06:34, 12 June 2021 (UTC)


 * Failed verification in some links consulted, bringing up concerns of WP:OR in the article:
 * There's no mention of Joseph Windmills in 1
 * Sentence listing the three clockmakers removed. Amitchell125 (talk) 06:21, 12 June 2021 (UTC)
 * The same source 1 does not support any of the following: George Graham who invented the deadbeat escapement, orrery and mercury pendulum - there's even no mention of orrery or mercury pendulum there;
 * Sorted. Amitchell125 (talk) 06:35, 12 June 2021 (UTC)
 * In the "Spiral-hairspring watch" subsection, there's no mention of Hooke or harmonic oscillator in the source.
 * Sorted. Amitchell125 (talk) 06:26, 12 June 2021 (UTC)

Article needs work. RetiredDuke (talk) 13:34, 27 March 2021 (UTC)
 * , your points are noted, and are being addressed; citations are being added where they are needed, and the existing ones checked (they are in many cases proving to be inadequate or incorrect). All the sentences will eventually each get properly cited, this is taking some time. Any inventors and inventions not present in the article will be included; including those mentioned above. Amitchell125 (talk) 06:41, 5 June 2021 (UTC)
 * Thanks for the ping, I haven't been able to keep an eye on the notices I've left, regrettably. The article looks much better now, and I know you are familiar with the FA process so that's very promising. I'm going to leave a comment on the FAR page saying there's lots of progress happening here, so there's no hurry in the process. Thank you for investing your effort on this, it's a very interesting subject. RetiredDuke (talk) 13:17, 5 June 2021 (UTC)
 * , the article has now reached the point when it needs to be checked through by others. I'll flag this up on the review page. Of course, please feel free to let me know of any issues if you get the opportunity to check through the text yourself. Amitchell125 (talk) 13:08, 19 August 2021 (UTC)
 * , thank you for the heads up, I will engage in the FAR page once I get the opp. to go through the article. RetiredDuke (talk) 19:51, 21 August 2021 (UTC)

Jyotisha (Vedic astrology)
Timekeeping is an essential tool in drawing any type of horoscope (horo =hour) yet Indian astrologers dance around the question of how birth times were recorded for commoners who later became famous. The rich elite could afford servants to oversee and maintain water clocks etc but sundials are useless at night or in the monsoon season. Yet it is glossed over as to how accurate birthtimes were ascertained and recorded.

No itinerant astrologer is capable of transporting a water clock in their travels and it would be easy to forget to turn a portable hourglass over. So just how did they record birth times? The Ascendant moves approximately one degree every four minutes so accurate timekeeping is absolutely indispensable in drawing up a chart.

I emailed one Hindu astrologer who came up with the ridiculous justification of using a 'moondial' at night... what if it's cloudy or raining? I have never come across a satisfactory explanation for this.. Every Jyotish practitioner dodges the question and dances around it as if I'm some kind of demon Ningnongtwit (talk) 08:11, 1 April 2021 (UTC)

A Commons file used on this page or its Wikidata item has been nominated for deletion
The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 19:22, 27 August 2022 (UTC)
 * Babylonian clay tablet - BM 29371.jpg

Smartphone anybody?
Although the smart phone, is not technically a timepiece, it has become "the clock" for hundreds of millions of people, and it is set to atomic clocks. I'll maybe try to add something, but someone with more energy for this article should add a section. History is now. cheers Billyshiverstick (talk) 03:00, 1 January 2023 (UTC)
 * Please replace all occurrences of "iPhone" with "smartphone" in your comment, and remove any redundant text. Most of the devices that have become "the clock" for people are probably Android phones, even if a lot of them are iPhones.  (And, as far as I know, they use similar clock-syncing mechanisms, syncing with mobile phone networks and with Network Time Protocol servers, the latter and probably the former ultimately providing syncing with "atomic clocks".) Guy Harris (talk) 09:27, 1 January 2023 (UTC)

Clarification about a point
Can someone confirm the authenticity of Henry de Vick's contribution stated in the introductory paragraphs? Did he create a mechanical clock in 1360? If so, was he the inventor of mechanical clocks or did he just make a particularly famous one as the article suggests? Noel Malik (talk) 21:34, 1 January 2023 (UTC)
 * No, it wasn't the first, or the "most famous" as the intro says, or even particularly famous. It's notability is that it is one of the few clocks from this early period for which a good, accurate drawing of the mechanics was made and has come down to us, so it has appeared in a lot of encyclopedias and antique clock books. Thanks for catching that. My feeling is that you can delete that undue weight sentence in the introduction.  Amitchell125 did an excellent rewrite a year ago, which corrected a lot of erroneous information.  --ChetvornoTALK 03:11, 3 January 2023 (UTC)