Talk:History of timekeeping devices/Archive 3

A-class review for Time
The following is a check list for WikiProject Time members to fill out when conducting the A-class review. Zginder 2008-05-14T02:29Z (UTC)
 * 1) Well-written [[Image:Yes check.svg|15px]] Zginder 2008-05-14T16:54Z (UTC)
 * 2) Reasonably clear
 * Escarpment is undefined and used a lot. Zginder 2008-05-14T16:54Z (UTC)
 * Er...Do you mean Escapement? Escarpment doesn't seem to do with timekeeping.  bibliomaniac 1  5  22:14, 14 May 2008 (UTC)
 * Yes, sorry for the mistake. Zginder 2008-05-15T13:16Z (UTC)
 * [[Image:Yes check.svg|15px]] Zginder 2008-05-17T23:46Z (UTC)
 * 1) Complete description of the topic
 * Marine chronometers were a revolution in navigation, but are hardly mentioned. Zginder 2008-05-14T16:54Z (UTC)
 * I added a section about them. Keilana | Parlez ici 02:47, 20 May 2008 (UTC)
 * [[Image:Yes check.svg|15px]] Zginder 2008-05-20T12:31Z (UTC)
 * 1) Meets How to write a great article. [[Image:Yes check.svg|15px]] Zginder 2008-05-14T20:12Z (UTC)
 * 2) Length suitable for the subject. [[Image:Yes check.svg|15px]] Zginder 2008-05-14T16:54Z (UTC)
 * 3) Well-written introduction
 * I have worked on the intro and think that is is now good. [[Image:Yes check.svg|15px]] Zginder 2008-05-17T21:12Z (UTC)
 * 1) Appropriate series of headings to break up the content.[[Image:Yes check.svg|15px]] Zginder 2008-05-14T16:54Z (UTC)
 * 2) Sufficient external literature references, preferably from reliable, third-party published sources with a reputation for fact-checking and accuracy
 * The early Early timekeeping devices sections are very well sourced, but the modern is more haphazard. Zginder 2008-05-14T16:54Z (UTC)
 * The reference format move will need to be completed. Zginder 2008-05-17T02:30Z (UTC)
 * What reference format should be used? Keilana | Parlez ici 03:01, 20 May 2008 (UTC)
 * I think he refers to the one suggested by Grimhelm. I don't use it, so I don't know how it goes.  bibliomaniac 1  5  03:22, 20 May 2008 (UTC)
 * Yes, that is what I meant, but that is more MOS than reference problem. [[Image:Yes check.svg|15px]] Zginder 2008-05-20T12:31Z (UTC)


 * 1) Well illustrated
 * Why do Candle clocks and Incense clock have no photo? Zginder 2008-05-14T16:54Z (UTC)
 * Formatting issues. We have a lot of long images that make it hard for us to fit an image for all the clocks. However, they're still in the articles.  bibliomaniac 1  5  22:16, 14 May 2008 (UTC)
 * I think I can skirt around MOS for the candle clock image. The incense clock one, however, has unsightly flash in it that obscures part of it, so I haven't included it. I'd like to look for a replacement image out in the internet.  bibliomaniac 1  5  02:37, 17 May 2008 (UTC)
 * [[Image:Yes check.svg|15px]] Although a appropriate picture of GPS (I can not find one that is relavent), a photo of non-sundial shadow clocks, and an animation would be nice. Zginder 2008-05-17T03:12Z (UTC)
 * 1) No copyright problems. [[Image:Yes check.svg|15px]] Zginder 2008-05-14T20:12Z (UTC)
 * 2) Could at least be considered for featured article status [[Image:Yes check.svg|15px]] Zginder 2008-05-14T16:54Z (UTC)
 * 3) Corresponds to the "Wikipedia 1.0" standard.
 * I looked at Encarta and this is better, it mentions the China also used burning knotted rope. I do not think this would be required to add, but something to think about. It does however not call shadow clocks sundials. As I stated early a sundial is a type of shadow clock not the other way around. Zginder 2008-05-16T13:00Z (UTC)
 * Regarding the Chinese knotted rope, I'm not finding any good sources other than Encarta, has anyone else found anything? As for the sundial/shadow clock thing, I thought that's what the article said. If not, that's probably what it should say. Keilana | Parlez ici 03:01, 20 May 2008 (UTC)
 * None of my sources mentioned knotted rope either. Either way, the article does not lose very much without the mention of knotted rope. We don't need to list every single thing people used to tell the time with.  bibliomaniac 1  5  03:22, 20 May 2008 (UTC)
 * [[Image:Yes check.svg|15px]] Zginder 2008-05-20T12:31Z (UTC)
 * 1) Very useful to readers. [[Image:Yes check.svg|15px]] Zginder 2008-05-14T20:12Z (UTC)
 * 2) A non-expert in the subject matter would typically find nothing wanting. May miss a few relevant points. [[Image:Yes check.svg|15px]] Zginder 2008-05-15T18:23Z (UTC)

I approve the promotion to A-class in WikiProject Time. I will try to get a second opinion. If I can not I will promote in a few days. Zginder 2008-05-20T12:31Z (UTC)

marine chrometer
take a look at came after Harrison's (which were very expensive). Parkinson and Frodsham made them cheaper so more ships bought them. Further info at. Of course an explanation of why it was important to know the correct time at Greenwich and how this knowledge was used to place the vessel would make sense of the piece. I can assist if you wish,but it is not difficult and I am away walking the hills of this country for a week or so from tomorrow so will look upon my return. Edmund Patrick ( confer work) 18:36, 15 May 2008 (UTC)

Did European mechanical clocks come from asia?
I'd like to question the unequivocal statement in 'Timekeeping devices in China' that: "Su Song's tower eventually led to mechanical clocks in Europe." The citation given for this is a UNESCO publicity magazine, which might not be considered a reliable source. The only scholarly evidence I know of for this idea is Joseph Needham's books, where it is presented as a hypothesis. The escapement in the Su Song tower was not similar to escapements in mechanical clocks, it still relied on the flow of water for timekeeping. Europe had it's own long tradition of complicated mechanisms, which many sources regard as sufficient to account for the development of the mechanical clock. -- Chetvorno TALK 21:13, 16 May 2008 (UTC)


 * I've found it repeated in several other sources. I think what separates Su Song's clock from clepsydra was that the water itself did not provide the measurement, it merely powered the machine. I haven't heard of a European horologe built before the 11th century though, but if there are records of such, please provide them.  bibliomaniac 1  5  21:35, 16 May 2008 (UTC)


 * From this very article: "The first [European] clock of which we have any record was built by the future Pope Sylvester II for the German town of Magdeburg, around the year 996." That would certainly seem to contradict the article's earlier statement, that "Su Song's tower [1088] eventually led to the development of mechanical clocks in Europe." --Grimhelm (talk) 22:46, 16 May 2008 (UTC)


 * Hmm. I found this when looking up the Magdeburg clock, suggesting that it might not have been a clock after all.  bibliomaniac 1  5  22:56, 16 May 2008 (UTC)


 * I don't see what that source shows (the Google books link only provides fragmentary details). My own quick check through Google books turned up this: "It was near the end of the tenth century, about the year 996, when he made at Magdeburg this clock so wonderful and surprising, as to go by means of weights," showing Sylvester's clock to have been mechanical.
 * The UNESCO source dates Su Song's clock ("greatest of all Chinese medieval clocks") to 1092, instead of 1088 as another online source quoted in this article. The exact wording of the UNESCO source also says: "Knowledge of the principles of Su Song's clock spreading to Europe led to the development of mechanical clocks in the West two centuries later."
 * This is contradicted by Thomas Reid's published source: "The writers of the 11th century speak in such a manner of clocks that it appears they must at that period have been well known." I think that published sources are to be preferred.  --Grimhelm (talk) 23:39, 16 May 2008 (UTC)


 * I think that the sources you've put up are better. I've removed the offending statement. Please, by all means, add your sources into the article.  bibliomaniac 1  5  23:51, 16 May 2008 (UTC)

What made Su's clock similar to the earliest true Western mechanical clocks was the fact that Su's clock featured an escapement (it also featured a chain drive, something that isn't mentioned in this article), but I don't think it served as any sort of model for what developed in Europe.-- Pericles of Athens  Talk 02:31, 7 August 2008 (UTC)

Dating (again).
I notice someone has changed a lot of the BCEs and CEs to BC and AD; are we using the standard system now? · AndonicO  Engage. 15:59, 21 May 2008 (UTC)
 * Not as far as I know, perhaps we should put in a couple of commented messages to the effect of "BCE and CE are used in this article, as it is about timekeeping in general, not one specific timekeeping system." I'll change them back, unless there's a general consensus to switch to Gregorian. Keilana | Parlez ici 23:34, 21 May 2008 (UTC)
 * Straw poll? I vote BC/AD. · AndonicO  Engage. 00:02, 22 May 2008 (UTC)
 * I support BC/AD, but I used BCE/CE because I was under the impression that we had decided to use that.  bibliomaniac 1  5  00:43, 22 May 2008 (UTC)
 * They are both Gregorian just different ways of stating them. Zginder 2008-05-22T02:10Z (UTC)
 * Yeah, 'tis the same. Which system do you think we should use, Zginder? · AndonicO  Engage. 02:42, 22 May 2008 (UTC)

(remove indent) Actually AD and BC are based on the Christian religion and Christian Calenders so are not the same as CE and BCE. The Jewish religion for example has used BCE and CE for sometime now. It uses the same finish and start point but CE and BCE have no specific religious connotations. Edmund Patrick ( confer work) 10:14, 22 May 2008 (UTC)
 * I was referring to the numbering system, the numbers stay the same: 3 AD = 3 CE; 3 BC = 3 BCE. · AndonicO  Engage. 10:34, 22 May 2008 (UTC)
 * apologies, thought you were talking about CE AD etc. Edmund Patrick ( confer work) 13:02, 22 May 2008 (UTC)
 * No worries. So at the moment, we have 2 for BC/AD, and 1 for BCE/CE, correct? · AndonicO  Engage. 13:07, 22 May 2008 (UTC)
 * I vote Gregorian AD/BC, for the same reasons as those we discussed earlier (it is the one with which most readers are familiar, the one which most of the article's sources seem to use, etc). I also notice that the year articles on Wikipedia use BC (eg. 20th century BC), so if we ever link to them it will bypass redirects. --Grimhelm (talk) 18:09, 22 May 2008 (UTC)
 * Both are Gregorian. The Gregorian calendar is the calendar of 12 months and 365.2425 days. What you are supporting is Anno Domini and not Common Era. Zginder 2008-05-22T22:10Z (UTC)

(outdent) So 3 for BC/AD and 1 for BCE/CE, so far. · AndonicO  Engage. 00:17, 23 May 2008 (UTC)
 * This should not be a vote, but I prefer Anno Domini (AD/BC). Keep in mind that AD goes before a date AD 2008 while all others go after. Zginder 2008-05-23T20:30Z (UTC)
 * Sometimes voting is not evil; lets us know where we stand. ^Roger on the "AD" being after the date. · AndonicO  Engage. 20:48, 23 May 2008 (UTC)

What was the final decision on this? (As if this contentious issue could ever be fully settled!) I ask because I notice an editor has just now changed the date to BC/AD, saying that they were reverting vandalism. Movingboxes (talk) 12:33, 8 August 2008 (UTC)
 * We decided BC/AD. · AndonicO  Engage. 12:43, 8 August 2008 (UTC)
 * Thank you for the speedy reply! :) Movingboxes (talk) 12:44, 8 August 2008 (UTC)

Subpage.
I'm working on some organizational changes here; it's a mess right now though, needs transitions... if this turns out alright, I'll leave another note here, and maybe we can implement the changes into the main article. (Note: if anyone wants to help, please feel free to.) · AndonicO  Engage. 11:46, 31 May 2008 (UTC)
 * Okay, I've pasted in the changes I made; the article isn't A-class anymore, but it'll be easier to get it to FA. · AndonicO  Engage. 14:34, 7 June 2008 (UTC)
 * Wait, why isn't it A-class anymore? Do we need to have another review? Nice job on the re-organization, by the way. Keilana | Parlez ici 14:36, 7 June 2008 (UTC)
 * Thank you, however, that "nice job" has left us with a desperate need for copyediting, since the transitions are all messed up. The only thing that's better is that it's chronological, but other than that it's a mess. Akin to mending a broken bone, but leaving behind a temporary cast, I suppose. · AndonicO  Engage. 15:01, 7 June 2008 (UTC)
 * At least it makes chronological sense. Perhaps we should make a checklist of stuff to go over before FAC?

Here's a proto-list:
 * Clean up transitions.
 * Check references.
 * Copy edit - repeatedly.
 * Make sure it conforms to MOS.

That's the basic idea, but I'm a bit concerned about the section 500 BC - 0 AD. Because it's really long, I was thinking that it would be a good idea to subdivide it based on device. Thoughts? Keilana | Parlez ici 16:46, 7 June 2008 (UTC)
 * I assume you meant 0 AD-1500 AD. Good idea; one question though, should we divide based on device (it would be somewhat choppy, I think?), location (might mess up the chronological order), or further divide it by time (complicated)? I agree with your proto-list, we're still not there (I'll try to find a few page numbers for the refs tomorrow). · AndonicO  Engage. 22:56, 7 June 2008 (UTC)
 * I think that either would work; if we organized it by country then it would be in a sort-of chronological order, because Egypt was early on, Greece and Rome were later, etc., but after the really early years it gets a bit confusing. If we organized it by device, and organized the devices by the time when they were used, it would be a viable option. Perhaps another opinion would be a good idea? Keilana | Parlez ici 04:57, 8 June 2008 (UTC)

I think that the chronological order is a mess. I really did prefer the previous format.  bibliomaniac 1  5  05:00, 8 June 2008 (UTC)
 * It's a mess now, but it had to be done, and will be easier to read once we copyedit a few more times. In any case, someone at FAC would have complained about the non-chronological order (again). · AndonicO  Engage. 09:12, 8 June 2008 (UTC)

Okay, so we have two possible organizations: by device and by region. Which looks best? · AndonicO  Engage. 18:37, 10 June 2008 (UTC)


 * Region looks better at this point, in my opinion.  bibliomaniac 1  5  20:27, 10 June 2008 (UTC)

References (again...)
Oh no, it's happening again. Can we please keep the pagenumbers in the footnotes? They are actually quite important for verifying facts in the article. And why are we going back from the Notes/References/FurtherReading system? Surely the article is better off with the sources laid out properly. (This has been explained before) --Grimhelm (talk) 08:41, 20 June 2008 (UTC)
 * Oh, I'm sorry. That was my doing; I'll fix it. Keilana | Parlez ici 15:13, 20 June 2008 (UTC)

Lead
The last paragraph of the lead seems loose and out of place. The information regarding Reagan and the Korean Air flight is tangential to the subject matter and of minor importance considering that the article covers nearly 4000 years of history. I’d strongly recommend ditching it, or at least rewriting it to focus more on atomic clocks than on GPS. 189.104.0.210 (talk) 00:58, 7 August 2008 (UTC)
 * I thought the same when I read it. I sort of skimmed the lead, got to the end and thought "Wait, what? Why is that here?" --Falcorian (talk) 01:53, 7 August 2008 (UTC)
 * I completely agree. It's so random and fringe-related to the subject matter. You might as well say "Famed musician Flavor-Flav often wore a quartz oscilator clock around his neck". I strongly reccomend deletion as well. Pepsi X Treme (talk) 05:08, 7 August 2008 (UTC)
 * I wrote it because we needed another paragraph; don't like it much either, but I'm short on time at the moment. Feel free to rewrite it. · AndonicO  Engage. 12:36, 7 August 2008 (UTC)
 * Better yet, get rid of it. It shouldn't be there at all - MOS:LEAD is a guideline, not an iron cast. Nousernamesleft (talk) 18:32, 7 August 2008 (UTC)
 * I see it's already gone. Never mind. Nousernamesleft (talk) 18:34, 7 August 2008 (UTC)

Digital?
I am a little surprised that there is nothing about the introduction of digital clocks/watches vs. analog clocks/watches. Obviously much of that relates to the introduction of quartz crystals and atomic clocks, but there can be digital devices that don't use either one and I think it would be a logical part of the History. Manassehkatz 01:57, 7 August 2008 (UTC)

"turn of the 14th century"
That phrase is in the lead. Does it mean the year 1300 or the year 1400? Inquiring minds want to know... Looie496 (talk) 03:16, 7 August 2008 (UTC)


 * It means the 1300s.  bibliomaniac 1  5  03:57, 7 August 2008 (UTC)

Pre-Quartz watch movements
Not sure if this is on topic or not but, in an effort to produce more accurate timekeeping by increasing the rate of oscillation, we had various electronic movements, including the 'tuning fork' escapements developed by Bulova. All of these could be seen as part of the development of the Quartz movement

OldDerbeian (talk) 08:20, 7 August 2008 (UTC)

Why no mention of internet timers/synchronizers?
It makes no sense. They are quite accurate and used all the time. --Leladax (talk) 08:34, 7 August 2008 (UTC)
 * You have to remember that the article is about timekeeping devices. NTP and similar are protocols to enable computer clocks to synchronise with other computer clocks (which may be synchronised with atomic clocks or other high accuracy clocks). If we're going to start talking about NTP, shouldn't we also talk about stuff like clocks on the news broadcast, via telephone, radio etc that were used by people to synchronise their clocks with a central clock before the widespread use of the internet and computers? Nil Einne (talk) 17:57, 7 August 2008 (UTC)
 * Then it's a double standard to include GPS. --Leladax (talk) 19:43, 7 August 2008 (UTC)

Why was this VITALLY IMPORTANT article rated as Mid-importance on the importance scale?
This article should at least be of High importance--if not Top! I am not kidding. Whoever rated it here is being either willfully or genuinely ignorant.

Time is vital and integral to so many parts of science, technology and society that it's almost taken for granted. We graph most phenomenon with respect to time. The vast majority of calculus concerns change over time. Time is so intimately associated with so many parts of mathematics that it can be hard to step back and see it. Every synchronous digital computer relies absolutely on a frequency.

Timekeeping represents our ability to measure and scale time. From thermodynamics to time-motion studies of insect wings and tectonic plates, to every sort of modelling and forecasting, time and frequency standardization is universally pivotal, strongly impacting the outcome of our observations and the quality of our methods.

Improvements in timekeeping instrumentation over the past 5000 years have led directly to groundbreaking advances for humanity. Perhaps beginning with agriculture, large, discrete improvements in time keeping have revolutionized navigation, physics, chemistry, earth sciences, medicine, communications, travel and business. It has even enabled space travel!

As a teacher I try very hard to integrate an appreciation of timekeeping into my classes. It's not supported by most texts more due to authors' knee-jerk adherance to politically derived standards than it's comparitive unimportance! The clock (in all its forms) deserves to join fire and the wheel among the greatest achievements of mankind, just as this article deserves to be rightly reassesed to an importance of Top or at least High. —Preceding unsigned comment added by 87.175.219.227 (talk) 18:52, 7 August 2008 (UTC)


 * It's in the frontpage. How much more importance do you want wikipedia to give it. --Leladax (talk) 19:45, 7 August 2008 (UTC)


 * I agree that mid-importance is an underestimate. It should be top-importance. Jason Quinn (talk) 20:13, 7 August 2008 (UTC)
 * Changed to "Top." If anyone disagrees, feel free to discuss/revert/drop it to "High." · AndonicO  Engage. 23:01, 7 August 2008 (UTC)
 * I've taken it down to High; the only Top articles are the very broadest ones, like "history of biology" and "history of technology". Other high-rated ones include, e.g., "history of evolutionary thought" and "history of electricity".--ragesoss (talk) 18:36, 8 August 2008 (UTC)

Precision vs. accuracy
At several points, this article mentions precision and/or accuracy of timekeeping in such a way as to suggest that the two are being confused for one another. It's important not to mistake precision for accuracy, even though it's easy to do that (not to mention difficult to prove it). For example, saying that something is 243.209347 seconds (or metres, or whatever) is precise, but it may not be accurate.

Thus, it would be good to specify, for example, how accuracy of timekeeping was improved, and keep that separate from precision (e.g., dividing time into smaller units).

--Piledhigheranddeeper (talk) 18:56, 7 August 2008 (UTC)

Pulsars
I think this article should make at least passing references to pulsars as they are among the most precise oscillators in nature and some come close to competing with atomic clocks in terms of accuracy. Jason Quinn (talk) 20:10, 7 August 2008 (UTC)
 * I wouldn't exactly call them "devices", though. GeeJo (t)⁄(c) &bull; 20:58, 7 August 2008 (UTC)
 * True, but a telescope observing the rotation rate of a pulsar is as much a timekeeping device as a sundial observing the rotation rate of the Earth. Splat (talk) 22:45, 7 August 2008 (UTC)
 * Telescopes don't "observe", and neither do sundials. Whoever is using the telescope or sundial makes the observations. A "timekeeping device" could no doubt be constructed based on observations of pulsars, but a telescope just ain't it. --Malleus Fatuorum (talk) 23:08, 7 August 2008 (UTC)
 * Point taken. Nevertheless, pulsars have been used to keep track of time to an accuracy within an order of magnitude of atomic clocks (see this citation).  That seems to merit a mention in this article. Splat (talk) 23:32, 7 August 2008 (UTC)
 * You could certainly build a clock whose calibration is based upon pulsars. How is such a clock anything less a time-keeping device compared to one based on the Cesium atom? Both just use regular periodic oscillations in nature. The word "device" refers to a clock itself, not the physical foundations for it. Regardless, my original intent for mentioning pulsars is that it is a possible alternative basis for time-keeping and I think important enough to warrant a sentence or two such that it alerts the reader to the topic's existence so they could pursue it further if they wish. Jason Quinn (talk) 23:40, 7 August 2008 (UTC)
 * There are many physical phenomena that could be used as the basis of a timekeeping device, but until they are I don't see their relevance to an article on the history of timekeeping devices. --Malleus Fatuorum (talk) 23:43, 7 August 2008 (UTC)

Indian timekeeping
This article completely ignores the contributions to time keeping from the cultures native to the Indian sub-continent. For example, the Jantar Mantar complex in New Delhi, India (ca. early 18 c.) is an excellent example of the advances of timekeeping and astronomy in this region. There are further examples in earlier literature (some dating into BCE) that indicate a culture well versed with the measurement of time. May I suggest a slightly broader perspective that is inclusive of all regions of the world rather than a narrow focus on just contributions from the supposed "classical world"? —Preceding unsigned comment added by 122.164.122.118 (talk) 09:32, 7 August 2008 (UTC)

Electric clocks
It is odd that the article makes only the shortest reference, in passing, to electric clocks, which were central in the timekeeping of the first half of the twentieth century. The Wikipedia already contains several articles on this topic: electric clock, Telechron, Hammond Clock Company, and perhaps others. Wissembourg (talk) 22:10, 7 August 2008 (UTC)

Stonehenge etc.
In the section "Early Timekeeping Devices" it says "Stone circles, such as England's Stonehenge, were built in various parts of the world, especially in Prehistoric Europe, to time and predict seasonal and annual events such as equinoxes or solstices." As there are no written records from these times we can only surmise what these stone alignments were used for, so it would be more accurate to say something about the celestial alignment and say that "this has lead many researchers to believe that they may have been used to predict annual events such as equinoxes and solstices". In fact, the online reference says "but its alignments show its purposes apparently included the determination of seasonal or celestial events" - which say to me "it appears that was the purpose." not that we know it was the purpose. Richerman (talk) 13:27, 8 August 2008 (UTC)

Escapement
The invention of mechanical clocks by the Chinese is a myth which rests on a, say, very optimistic interpretation of their escapement mechanism. We do not need to rewrite history that the true escapement mechanism for mechanical clocks was invented in medieval Europe. Ricardo Duchesne: “Asia First?”, The Journal of the Historical Society, Vol. 6, No. 1 (March 2006), pp. 69-91 (77-79):

None of what Hobson says, however, addresses Landes’s carefully weighted opposition to Needham, which is detailed in his book, Revolution in Time (1983). Chinese horology never got beyond the principle called clepsydra, which is the measurement of time by the continuous flow of water. What the Sung Chinese did was to bring to its culmination the water-clock line of horological development. The Europeans, on the other hand, started a whole new line of clock technology based on a true mechanical or kinematic principle of measurement. The escapement by itself is not the key. Since there is so much confusion about this difference, and not just from Hobson, it is worth citing Landes’s explanation of the different principles of operation as explained in his Revolution in Time:

Both techniques used escapements, but these have only the name in common. The Chinese one worked intermittently; the European, in discrete but continuous beats. Both systems used gravity as the prime mover, but the action was very different. In the mechanical clock, the falling weight exerted a continuous and even force on the train, which the escapement alternately held back and released at a rhythm constrained by the controller. Ingeniously, the very force that turned the scape wheel then slowed it and pushed it part of the way back. . . In other words, a unidirectional force produced a self-reversing action— about one step back for three steps forward. In the Chinese timekeeper, however, the force exerted varied, the weight in each successive bucket building until sufficient to tip the release and lift the stop that held the wheel in place. This allowed the wheel to turn some ten degrees and bring the next bucket under the stream of water while the stop fell back. . . In the Chinese clock, then unidirectional force produced unidirectional motion.

Landes knows that early mechanical clocks were less accurate than the Chinese water-wheel clocks. The important difference is that, by Sung times, water clock techniques had “come about as far as they could, whereas the mechanical clock marked the beginning of a new technology.” Water-clock technology is intrinsically limited by many destabilizing factors, such as corrosion and dirt, or the temperature of the water. The mechanical clock is inherently capable of far greater precision and has far greater developmental possibilities. If Needham thinks the Chinese escapement can be seen as an anticipation or precedent of the mechanical escapement, the historical reality is that after the invention of a few astronomical water clocks in the Tang and Sung era, Chinese horology stagnated and then retrogressed. Needham imagines that this escapement device was transmitted to Europeans but says that “the details of any transmission are still obscure,” and Landes convincingly argues that no historical source has so far been discovered showing any clear transmission. Besides, if true, this transmission would still not explain the invention of a clock that measured time, not according to the continuous flow of water, but as a regular, repeating sequence of discrete actions. Nor does it explain the rapid spread of this new mechanical device, and indeed the “relentless pressure to improve technique and design,” from the first crude mechanical clocks which kept time so imperfectly that they had to be continually adjusted, to the spectacular improvement in precision Christian Huygens (1656) achieved by replacing the balance-wheel regulator with a pendulum, and so on in cumulative succession.

I am going to change the article accordingly. Has anybody checked the Arab claim of "weight-driven clocks"? That is a strongly misleading claim, too, because the weights of these clocks was actually water! By that creative reasoning already the earliest Egyptian water clocks were weight driven.....Gun Powder Ma (talk) 23:55, 20 August 2008 (UTC)


 * The section on the so-called Muslim mechanical clocks is bogus. It totally misrepresents its main source which, in fact, does not credit the Arabs for mechanical clocks, but only for certain components of mechanical clocks. I could not find not a single instance where the author explicitly claims a Muslim invention of mechanical clocks. But see for yourself: http://www.history-science-technology.com/Articles/articles%2071.htm Gun Powder Ma (talk) 00:11, 21 August 2008 (UTC)
 * Brilliant quote. Yi Xing, Zhang Sixun, and Su Song still need to be mentioned as employing the escapement mechanism, yet it should be stressed that the Chinese escapement was driven by the motion of liquid power, and not by a sequence of purely mechanical actions as seen in European clockworks soon after.-- Pericles of Athens  Talk 18:04, 21 August 2008 (UTC)
 * Yet, wasn't this painfully obvious already with the description of a waterwheel and clepsydra tank in Su's clock tower?-- Pericles of Athens  Talk 18:05, 21 August 2008 (UTC)
 * I've left a message for Jagged85 regarding this discussion (he added the edits, I believe). · AndonicO  Engage. 11:33, 2 September 2008 (UTC)


 * Thanks for inviting me to the discussion. The cited article explicitly states that Arabic engineers employed weight-drives in their mercury clocks. Jagged 85 (talk) 18:08, 3 September 2008 (UTC)


 * Where does it? I post a whole excerpt, but you just repeat your point and remove the tag. This is not the first time you 'worked' that way. Ahmad Y al-Hassan & Donald R. Hill: “Islamic Technology”, Cambridge 1986, ISBN 0 521 422396, Water-clocks and mechanical clocks, pp.55-59, make the first explicit mention of Islamic mechanical clocks for the first time in connection with Taqi al-Din (16th c.). Gun Powder Ma (talk) 23:00, 4 September 2008 (UTC)


 * I cleared up the old section, consisting of dubious quotes taken out of context from online websites, and wrote a new section based on reliable print sources. Gun Powder Ma (talk) 03:01, 11 September 2008 (UTC)


 * Where did I say "mechanical clocks"? I said that their mercury clocks had weight-drives... the quote you posted above didn't even address the mercury clock. Please carefully read what I say before throwing around accusations, but I guess this is not the first time you 'worked' that way either. Either way, I'm glad you did finally get around to addressing the mercury clock in the article itself, so cheers to that. Jagged 85 (talk) 01:54, 14 September 2008 (UTC)

Global Positioning System
Does the GPS section really belong here? GPS is a positioning system, not primarily a timekeeping system. While it may include sophisticated clock-synchronisation methods, that alone doesn't mean it should be included here. As has previously been mentioned, NTP isn't included either.

Perhaps we should have a section called Clock synchronisation (with link to main article Clock synchronization) that briefly describes the general requirement for clock sync, with a brief mention of NTP and GPS as examples. Mitch Ames (talk) 03:20, 3 February 2010 (UTC)
 * GPS is the standard clock for many systems requiring high absolute accuracy, so I would support its inclusion. The low cost and high quality are a silent revolution in many ways.  All the best: Rich Farmbrough, 16:42, 24 July 2014 (UTC).

New text about Persian clocks - degrading Featured Article status
User:Maahmaah has added some paragraphs about the history of clocks in Persia. Whilst added in good faith, I do not feel that they are of an appropriate quality for Wikipedia, and certainly not for a featured article. (Maahmaah is not a native English speaker and I do not mean any disrespect to him.) I've had a go at cleaning up the text, but it's still not great. It is not helped by the fact that the only cited source is in the Persian language. Can anyone help to address this issue before I take it to WP:FAR? Thanks, Bazonka (talk) 20:22, 26 February 2012 (UTC)

Wristwatches - too definite?
From the current version of the article:


 * In 1904, Alberto Santos-Dumont, an early aviator, asked his friend, a French watchmaker called Louis Cartier, to design a watch that could be useful during his flights. The wristwatch had already been invented by Patek Philippe, in 1868, but only as a "lady’s bracelet watch", intended as jewelry. As pocket watches were unsuitable, Louis Cartier created the Santos wristwatch, the first man's wristwatch and the first designed for practical use.

This claim appears in various forms over a handful of pages, but I am not sure it's accurate. The Santos wristwatch may have been the first successful man's wristwatch, but it certainly wasn't the first designed for practical use - as I write this, I'm looking at an 1898 publication (from Calcutta, so it was presumably mainstream by the time it got there) showing a "wristlet" watch explicitly advertised to cyclists as a functional item. This may need rephrasing a little. Andrew Gray (talk) 23:02, 16 November 2012 (UTC)

HIST406 Wikipedia article critique
This article is one of the best Wikipedia articles I have seen in quite some time. The introduction provides a very nice and short summery of a long article, which is a feat in of itself. The table of contents is very well organized and makes it extremely easy to find what is needed. Each section contains a fully fleshed out history of time-keeping instruments from the time period it represents. Everything is organized in chronological order and flows very nicely from example to example. Furthermore, the article includes dozens of very detailed and varied pictures of all kinds of clocks, every single one of them relevant and helpful. If I had to name a flaw for this article, it's that despite being very well organized, it is still extremely long and splitting it into several different articles should be considered. In particular, more than a small portion of the article is dedicated to very specific types of clocks that may be considered material for stand alone articles as opposed to being a part of one huge article. The references appear to be credible and I did not find any missing footnotes, so no problems there. All in all a very well written and strong article. — Preceding unsigned comment added by HIST406-13sdehart (talk • contribs) 21:58, 20 February 2013 (UTC)

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