Talk:Metre

British vs American spelling
Recently there has been some editing of the first sentence between: The reasoning given for the second version was that British spelling is the default for practically all countries and American spelling is the outlier, therefore we don't need to specify "British". This is not quite true because many countries (especially those in Asia) do not officially follow British or American spelling but instead leave it to individual choice (often depending on where the teachers originated from and many other factors). So "metre" is not the default for many people in Asia.  Stepho  talk 10:42, 31 October 2022 (UTC)
 * 1) The original: "The metre (Commonwealth spelling) or meter (American spelling; see spelling differences)"
 * 2) The edited version: "The metre or meter (American spelling; see spelling differences)"


 * That argument reinforces the point that "metre" is not only British spelling, but it appears to personal observation. Instead we can simply observe WP:LEAD. The lead should summarise the body, and the body's Metre identifies "metre" as the standard spelling in English-speaking countries except in a couple of specific cases. NebY (talk) 11:11, 31 October 2022 (UTC)
 * It has nothing to do with "personal observation". The word is French, which obviously the British used, and the Commonwealth as well.
 * This means that the British use the original spelling, whereas the article claims it is commonwealth spelling, which is blatantly incorrect.
 * The word is spelled "metre". That is the correct spelling of the word. The US variant, meter, is a variant of the correct spelling of the word.
 * We would not say that "colour" is a commonwealth spelling. Go read the article, it clearly says "British English". This is correct, as the French original word is "couleur".
 * Metre, however, is the correct French spelling, nothing to do with british spelling, or the commonwealth, it is simply de facto the correct spelling of the term and the word. Chaosdruid (talk) 17:39, 10 November 2022 (UTC)
 * Just to clarify, I meant (but I guess put it too briefly) that the argument that "many countries (especially those in Asia) do not officially follow British or American spelling but instead leave it to individual choice" appears to be personal observation, and that it reinforces the point that "metre" is not only British spelling. NebY (talk) 18:33, 10 November 2022 (UTC)
 * +1 for the comments above that metre is a "British spelling"; it's not. It's the international English spelling in both senses of the word: (1) it is the spelling used by all English-speaking countries that are not the US, and (2) it is the official spelling used by the BIPM, an international institution that controls the SI. This whole "British" spelling vs. American spelling is an incorrect dichotomy; the dichotomy is almost always Commonwealth vs. American spelling in general, but in this case (and other SI-related matters), it goes even beyond that to being an international vs. American one. I'm surprised this edit was even challenged/reverted; this should not even be something to be debated, since it is a widely known fact. Getsnoopy (talk) 22:17, 16 November 2022 (UTC)
 * "Metre" is a British English spelling, and, as with other British English spellings, spread around the world during the expansion of the British Empire. The US, following their early independence, evolved their own spellings from the early 1800s.
 * And even the BIPM concede in their "brochure", that there are international spelling variations in English. There they say:.
 * Which spelling they choose to use for their house publications is of no consequence or relevance to the subject or to Wikipedia, especially as the BIPM were so late on the scene, being formed in 1875, several decades after both the British and US spellings entered the lexicon.
 * So I agree that, as this article is about a subject that has two recognised English spellings, they should both appear, in bold, early in the lead, and that they should be described as the British and US spellings. -- DeFacto (talk). 09:00, 17 November 2022 (UTC)
 * Thank you for the reminder that ISO and IEC (international organisations, not British or British Commonwealth ones), use "metre" in their English-language publications. NebY (talk) 20:17, 18 November 2022 (UTC)
 * since america does not yet use the metric system it wouldn't make sense for the article name to use the american variant NotOrrio (talk) 12:17, 2 January 2023 (UTC)
 * Personally, I balk at the spelling 'metre'. But this applies to all the other words where the British spelling has 'the last 2 letters backwards': 'litre', 'centre', 'acre', etc. This is a British ideosyncrasy in general therefore the 'metre' spelling will always be associated with 'British'. In German, we use 'meter' as well therefore the American variant in this case is more sympathetic to me. Many other non-english speaking countries use 'meter' as well, because that better aligns spelling with pronounciation. In that sense, 'international' usage should be seen against the background of all users of English. I think this is the point the OP was trying to make re usage in asia. I would rather live in a world where one writes 'meter' if one speaks 'meter', that consideration should be more important than questions of origin or historical priority. Ariescode (talk) 22:17, 2 April 2023 (UTC)
 * Exactly, it needs to be reverted back to 'meter'. Why is color then not colour on wiki?? Most of the world says meter: https://www.indifferentlanguages.com/words/meter Bodpm (talk) 22:07, 20 December 2023 (UTC)
 * already censoring, . Then why color and not colour will you revert that??  Bodpm (talk) 22:48, 20 December 2023 (UTC)
 * Such eloquence of the English language. Such a shining example of forming consensus with enlightened points.
 * That website is American (Arizona to be exact), so of course it spells it as "meter", even when listing pronunciation for multiple regions. It also doesn't list any English speaking countries. Outside of the US, "metre" is far more common than you think, especially among the British Commonwealth countries.
 * "Colour" is quite common on WP, as is "color". WP:ENGVAR is our principle guideline and basically says that the first editor chooses among valid spellings and then we stick to it unless the topic is explicitly tied to a particular country (not the case here).
 * One of the reverts done to you was because the article title is "metre" and you tried to put your personal preference of "meter" first and the form of the article title second.  Stepho  talk 23:09, 20 December 2023 (UTC)

History duplication
Metre and History of the metre overlap widely. WP:SS should be applied, leaving only the latter's lead in place of the former's section. fgnievinski (talk) 04:37, 14 August 2023 (UTC)


 * Hello I don't agree with your proposition. I think the informations in the section History of definition in the article Metre are very important there, because they illustrate the role that measurement has in science and the role the metric system had in the transition from geophysics to physics. This role is much more important than the accuracy of the historical definition of the metre.Charles Inigo (talk) 08:11, 26 August 2023 (UTC)
 * Whatever focus, there shouldn't be two versions of the history of the metre; hence the merger. fgnievinski (talk) 19:13, 26 August 2023 (UTC)
 * Agree, merge, as they overlap so widely. Obviously I share the concerns of other users that this merger should not result in the deletion of material, as long as it is relevant to the history of the metre.---Ehrenkater (talk)
 * Maybe the article History of the metre should be suppressed?Charles Inigo (talk) 06:45, 28 August 2023 (UTC)
 * It's a notable topic (WP:N), hence it deserves a separate article. Would you oppose WP:SS? fgnievinski (talk) 20:06, 28 August 2023 (UTC)
 * I personnaly contributed a lot in the article History of the metre and to its translation in French. It was very useful as a draft for contributions which were displaced in other articles. In my opinion the article was at his origin depreciating for the metre and for contributions to it by other country than United Kingdom. I think that the section Metre presents the valuable contributions of United States to the metric system Worldwide adoption thanks to a Swiss immigrate. It explains the real role of least squares in the history of the metre i.e. the proposal by Bessel of his reference ellipsoid which was not even mentionned in Ken Alder's book. I am afraid that the suppression of the section Metre would be a political choice as the article Metre is linked to translations in 166 languages, while the article History of the metre is translated in only four languages. Nevertheless, I think the idea of a summary of the History of the Metre must be kept at the beginning of the article Metre and I am afraid that it will be resumed as an ovesimplification as such as: "the metre was invented by the founders of the Royal Society in 1660 as the length of a pendulum". Such oversimplifications prevent the understanding by novice readers of basic knowledges in physics i.e. the fact that the pendulum length was a mean to measure gravity and proved to be crucial for determining the flattening of the Earth which was essential in the History of metre. I think the section Metre in its present form has already an acceptable format. Charles Inigo (talk) 06:12, 30 August 2023 (UTC)
 * Based on your report, it seems we have a more serious matter: point-of-view fork. That only makes it more important to merge the two versions of the history of the metre into a single cohesive version. I have no preference for which version to keep. In fact, section Metre is so large, it could well replace the whole of History of the metre if the latter is not neutral. fgnievinski (talk) 01:30, 31 August 2023 (UTC)
 * I really don't think we are confronted to a point of view fork and the section History of definition of the article Metre just summarizes with some ameliorations in conceptualization the article History of the metre which has been ameliorated since. Charles Inigo (talk) 13:35, 1 September 2023 (UTC)
 * Please read Summary style. A "summary" cannot have several sections and detailed tables, as there are in Metre. It's supposed to be just a couple of paragraphs. Ideally, exactly the lead of the spined off article, History of the metre. fgnievinski (talk) 19:34, 1 September 2023 (UTC)
 * Agreed.---Ehrenkater (talk) 10:56, 19 October 2023 (UTC)
 * There is a conceptualization issue which is linked to the subsection difference between the two texts ie the sections of the article History of the metre and the subsections of the section History of definition in the article Metre. As Charles Édouard Guillaume wrote it, at is origin, the metre had two definition one ten-millionth of the Earth quadrant wich was kept as the Mètre des Archives. As he quoted the first definition is historical and the second definition (the first practical realization of the metre) is metrological. When the metre was choosen has an international unit the second definition was prefered. It was decided that the length of the metre ie the length of the international prototype metre bar would be identic to that of the Mètre des Archives which was deduced by definition from geodetic standards calibrated on the toise, but as Charles Édouard also quoted it was the discrepancy between the length of the different standards calibrated on the toise which was at the origin of the proposal of the creation of the BIPM and the distribution of the international prototype metre bars. It was proposed in the article History of the metre to suppress the section Meridional definition with a link towards the article Meridian arc of Delambre and Méchain in order to keep only the sections Universal measure, Mètre des Archives, International metre prototype bar and so on. The subsections in the section History of the definition of the article Metre are Pendulum or meridian, Meridional definition, International prototype metre bar and so on. In my opinion the second option proved to be the best firstly because it allowed to rapidely settle the matter of the pendulum length, mentionning that it had been considered by the French scientists who were making efforts to determine the size of the Earth. Secondly the sub section Meridional definition (which is not a summary of the article Meridian arc of Delambre and Méchain to be developed) is kept in a very short form in the article Metre mentioning that this definition was used to calibrate geodetic standards thanks to standard of the metre (and througth comparison with Borda double toise N1 from which the metre had been deduced in the case of the Spanish Standard) which proved to be crucial in the decision of creating the BIPM and to distribute the international prototype metre bars. The discussion on the geodetic standards alows to discuss thermal expansion and to explain that correction of temperature errors was the essence of the scientific project that motivated the creation of the BIPM hence Charles Édouard Guillaume's Nobel Prize. I think that sections focused only on the definition of the practical realizations of the metre would miss the focus and prevent readers to understand that the adoption of the metre and the creation of the BIPM was a scientific project in itself linked principally to geodesy at the time when errors were considered in sciences. For these reasons I propose to rename the subsection International prototype metre bar of the article Metre and to call it Creation of the International Bureau of Weights and Measures. The section History of definition in the article Metre could be renamed Historical definition and creation of the BIPM keeping only the first three subsections, when the article History of the metre should be renamed History of the practical realizations of the metre with a link redirecting to it in the section Actual definition of the metre to be placed after the section Historical definition and creation of the BIPM in the article Metre. So the two article wouldn't share any more the same scope. The renamed article History of the metre ie History of the practical realizations of the metre could continue to give in introduction an history of universal mesure centered in the progression towards dematerialisation of the units of length and in which the choice of the metre could be summarized with a link towards the article Metre, while the article Metre could continue to contain a section centered on the historical definition of the metre and on the role of the U.S. Coast Survey and of the first scientific associations, created in central Europe half a century before World War I, in the creation of the BIPM. Charles Inigo (talk) 03:11, 2 September 2023 (UTC)
 * This article's material on the history of the metre needs a tighter focus and tighter expression; it should not be used as a vehicle for the history of the development of the metric system and its institutions, and it should certainly include the realisation of the metre. It's the combination of circuitous phrasing, digressions, excessive depth and extraneous purposes which render it almost impenetrable, much as the passage above but on a larger scale. I don't suggest you try to fix that; rather, if you pause your editing then others will be able to take the time to make cumulative improvements piece by piece. NebY (talk) 18:24, 2 September 2023 (UTC)
 * Ok and sorry. Charles Inigo (talk) 21:20, 2 September 2023 (UTC)
 * Thank you. NebY (talk) 23:07, 3 September 2023 (UTC)
 * A look at the other language versions (through Google Translate) might help: fr:Mètre, de:Meter, es:Metro, ja:メートル. fgnievinski (talk) 23:12, 3 September 2023 (UTC)
 * Thank you for your suggestion. Charles Inigo (talk) 12:41, 6 September 2023 (UTC)
 * I suggest that you consider the possibility to tranlate the Wikipedia article Histoire du Mètre in French into English. In my opinion this version is better than the present version of the Wikipedia article History of the metre. Charles Inigo (talk) 18:21, 19 September 2023 (UTC)


 * You could also sumarize the section history of definition as something like that :


 * ===Universal measure: the metre linked to the figure of the Earth===


 * Scientific revolution began with Copernicus work. Galileo discovered gravitational acceleration explaining the fall of bodies at the surface of the Earth. He also observed the regularity of the period of swing of the pendulum and that this period depended on the length of the pendulum.


 * Kepler's laws of planetary motion served both to the discovery of Newton's law of universal gravitation and to the determination of the distance from Earth to the Sun by Giovanni Domenico Cassini. They both also used a determination of the size of the Earth, then considered as a sphere, by Jean Picard through triangulation of Paris meridian. In 1671, Jean Picard also measured the length of a seconds pendulum at Paris Observatory and proposed this unit of measurement to be called the astronomical radius (French: Rayon Astronomique). In 1675, Tito Livio Burattini suggested the term metro cattolico meaning universal measure for this unit of length, but then it was discovered that the length of a seconds pendulum varies from place to place.


 * Christian Huygens found out the centrifugal force which explained variations of gravitational acceleration depending on latitude. He also discovered that the seconds pendulum length was a means to measure gravitational acceleration. In the 18th century, in addition of its significance for cartography, geodesy grew in importance as a means of empirically demonstrating the theory of gravity, which Émilie du Châtelet promoted in France in combination with Leibniz's mathematical work and because the radius of the Earth was the unit to which all celestial distances were to be referred. Indeed, Earth proved to be an oblate spheroid through geodetic surveys in Ecuador and Lapland and this new data called into question the value of Earth radius as Picard had calculated it.


 * According to Alexis Clairaut, the study of variations in gravitational acceleration was a way to determine the figure of the Earth, whose crucial parameter was the flattening of the Earth. After the Anglo-French Survey, the French Academy of Sciences commissioned an expedition led by Jean Baptiste Joseph Delambre and Pierre Méchain, lasting from 1792 to 1799, which attempted to accurately measure the distance between a belfry in Dunkirk and Montjuïc castle in Barcelona at the longitude of the Paris Panthéon. When the length of the metre was defined in 1799, the flattening of the Earth was assumed to be 1/334.


 * In 1841, Friedrich Wilhelm Bessel using the method of least squares calculated from several arc measurements a new value for the flattening of the Earth, which he determinated as 1/299.15. He also devised a new instrument for measuring gravitational acceleration which was first used in Switzerland by Emile Plantamour. Charles Sanders Peirce and Isaac-Charles Élisée Cellérier (8.01.1818 – 2.10.1889), a Genevan mathematician soon independently discovered a mathematical formula to correct systematic errors of this device which had been noticed by Plantamour and Adolphe Hirsch. This allowed Friedrich Robert Helmert to determine a remarkably accurate value of 1/298.3 for the flattening of the Earth when he proposed his ellipsoid of reference in 1901. This more than 25 years after the Metre Convention, when the metre was adopted as an international scientific unit of length for the convenience of continental European geodesists following the example of Ferdinand Rudolph Hassler.


 * Does that sound better? Charles Inigo (talk) 12:35, 28 September 2023 (UTC)
 * Disagree with merge. The duplication arises only because, due to the efforts of one editor, Metre contains a deep dive into history, packed with lists of names and multiple references, tracking minute steps in early conceptions of the unit. This doesn't serve our readers. Metre should contain a readable summary of the history (and not transclusions of detail from the History article).
 * NebY (talk) 09:24, 20 October 2023 (UTC)

This suggested passage seems to go in the opposite direction from the request to make the history section of this more of a summary of "History of the metre". Also I dispute "metre was adopted as an international scientific unit of length for the convenience of continental European geodesists". About the same time that the Meter Convention was adopted, industry was achieving ever-improving accuracy, and the stability of existing national standards of length was marginal for the needs of industry. The stability of the standards distributed as a result of the Meter Convention was a significant improvement over earlier standards and met the needs of industry until the definition of the meter was changed to a light-wavelength standard in the mid 1900s. Jc3s5h (talk) 13:59, 29 September 2023 (UTC)


 * I think you could find a lot of discourses of official ceremonies (for example: Spuller, Eugène (1889), Compte rendus de la première Conférence générale des poids et mesures) mentioning the role of scientists of that time in the adoption of the metre. Members of commissions like the Commission of the Metre belonged to the first scientific associations founded in central Europe in the 19th century. I cite representatives of Germany, Russia, Switzerland and Spain to the diplomatic Conference of 1875 who were eminent members of scientific associations for instance the International Association of Geodesy and the World Meteorological Organization: Adolphe Hirsch, Carlos Ibáñez e Ibáñez de Ibero, Wilhelm Foerster and Heinrich von Wild also members of the International Committee for Weights and Measures. The question is further discussed in the section International metre prototype bar which has been summarized removing excessive intricated details. You should also keep in mind that the more powerful scientific association at that time was not the Magnetischer Verein founded by Gauss, but the International Association of Geodesy which was crucial for development of industry as cartography was necessary for creating the infrastructures needed for the industrial development. As this was mainly a continental European and American adventure, what sounds to me a chauvinistic British view tends to focalize on artifacts made by Johnson Mattey in the process of uniformisation rather than on mastering of thermal expansion and thermometric work of the BIPM and its applications in cartography which was sanctionned by Guillaume's Nobel prize.
 * The passage "metre was adopted as an international scientific unit of length for the convenience of continental European geodesists" is supported by Pérard source n° 33, p. 28:
 * « A ce moment, Ibáñez n'avait pas seulement en vue les besoins immédiats de la géodésie européenne [...] sa claire vision lui permettait également d'écrire:" c'est à cette heureuse coïncidence de vue et de caractères que l'Europe et une partie de l'Amérique devront un jour l'unification des poids et mesures". Or, cette collaboration scientifique internationale allait se révéler encore plus féconde qu'Ibáñez n'osait l'imaginer; elle portait en puissance une extension quasi indéfinie ».
 * It is also supported by Adolph Hirsch in Le général Ibáñez notice nécrologique lue au comité international des poids et mesures, le 12 septembre et dans la conférence géodésique de Florence, le 8 octobre 1891, Neuchâtel, imprimerie Attinger frères, also available in Comptes-rendus des séances de la Commission permanente de l'Association géodésique internationale réunie à Florence du 8 au 17 octobre 1891 Internationale Erdmessung. Permanente commission De Gruyter, Incorporated 234 pages p. 105-106:
 * « Les relations intimes qui existent nécessairement entre la Métrologie et la Géodésie expliquent que l'Association internationale, fondée pour combiner et utiliser les travaux géodésiques des différents pays, afin de parvenir à une nouvelle et plus exacte détermination de la forme et des dimensions du Globe, ait donné naissance à l'idée de reformer les bases du Système métrique, tout en étendant celui-ci et le rendant international. Non pas, comme on l'a supposé par erreur pendant un certain temps, que l'Association ait eu la pensée peu scientifique de modifier la longueur du mètre, afin de la conformer exactement à sa définition historique d'après les nouvelles valeurs qu'on trouverait pour le méridien terrestre. Mais, occupés à combiner les arcs mesurés dans les différents pays et à rattacher les triangulations voisines, nous avons rencontré, comme une des principales difficultés, la fâcheuse incertitude qui régnait sur les équations des unités de longueur employées. Étant tombés d'accord avec le général Baeyer et le colonel Ibáñez, nous avons décidé, pour rendre comparables toutes les unités, de proposer à l'Association de choisir le mètre pour unité géodésique, de créer un Mètre prototype international différant aussi peu que possible du Mètre des Archives, de doter tous les pays d'étalons identiques et de déterminer de la manière la plus exacte les équations de tous les étalons employés en Géodésie, par rapport à ce prototype; enfin, pour réaliser ces résolutions de principe, de prier les gouvernements de réunir à Paris une Commission internationale du Mètre. Cette Commission fut en effet convoquée en 1870 ; mais, forcée par les événements de suspendre ses séances, elle n'a pu les reprendre utilement qu'en 1872. [...] Il serait oiseux d'insister […] sur les résolutions de principe votées par la Commission du Mètre ; il suffit de rappeler que, pour assurer l'exécution de ses décisions, elle avait recommandé aux Gouvernements intéressés la fondation à Paris d'un Bureau international des poids et mesures, et qu'elle a nommé une Commission permanente dont le général Ibáñez (il avait été promu en 1871 à l'emploi de général de brigade) a été élu président. En cette qualité de président de la Commission permanente, le général Ibáñez, appuyé par la grande majorité de ses collègues, a su vaincre, avec une fermeté admirable et infiniment de tact, tous les obstacles qui s'opposaient à la réalisation complète des décisions de la Commission du Mètre, et surtout à la création d'un Bureau international des poids et mesures. Les Gouvernements, convaincus de plus en plus de l'utilité d'une telle institution dans l'intérêt des sciences, de l'industrie et du commerce, se sont entendus pour convoquer au printemps de 1875 la Conférence diplomatique qui a abouti, le 20 mai de la même année, à la conclusion de la Convention du Mètre. Par la finesse déliée de son esprit diplomatique autant que par sa grande compétence scientifique, le général Ibáñez, qui représentait l'Espagne dans la Conférence, a contribué beaucoup à cet heureux résultat, qui devait assurer à plus de vingt États des deux mondes et à une population de 460 millions d'âmes la possession d'un système de Poids et Mesures métriques, d'une précision inconnue jusqu'alors, complètement identiques partout et offrant toutes les garanties d'inaltérabilité. »
 * I also would like to mention that, as Carlos Ibáñez e Ibañez de Ibero mentioned it, metrology had long been a subdiscipline of geodesy, which was linked to astronomy. Astonomers and scientists like Bessel, Borda or Ferdinand Rudolph Hassler devised measuring devices which they, at least in Europe, compared to other devices used by other geodesists. Guillaume's Nobel prize marks the end of an era when metrology was part of geodesy which developed in France with the creation of the French Academy of Science, hence the location of the BIPM. The use of the Committee Meter as a standard of the metre for calibration of Hassler's baseline apparatus long before 1889 demonstrated that the International prototypes would be an acceptable way to unify the system. But base line measurement through invar wire was then preferred. Charles Inigo (talk) 09:41, 30 September 2023 (UTC)
 * I changed the title of the section Meridional definition for Early adoption of the metre as a scientific unit of length: the forerunners which souds more logical between the section Universal measure: the metre linked to the figure of the Earth and the section International prototype metre bar where is explained that such prototypes fomalized the international adoption of the metre as a scientific unit of length.  Charles Inigo (talk) 07:11, 5 October 2023 (UTC)
 * I recreated a section Meridional definition copying material from the Wikipedia article Seconds pendulum on the Sixth of October 2023. Charles Inigo (talk) 08:33, 7 October 2023 (UTC)
 * @Charles Inigo duplicating text across multiple articles is not a good practice, because sooner or later one version will be improved and the other will become outdated. Please consider using template:excerpt instead. fgnievinski (talk) 00:43, 8 October 2023 (UTC)
 * I agree with you but in order to avoid impenetrable prose, I have to reuse some formulas of articles which should be improved. In order to palliate my little English and conforming to wikipedia respect of intellectual property, I indicate when I duplicate text. I apologize for the inconvenience. Charles Inigo (talk) 14:55, 8 October 2023 (UTC)
 * I suggest a change in the susections of the section History of definition of the article Metre. The section should be shared in two subsection the first called Universal measure: the metre linked to the figure of the Earth and the second Metrology and paradigm shift in physics. The text doesn't need to be expanded as the content of the subsection Universal measure: the metre linked to the figure of the Earth introduce the three subsections Meridional definition, Early adoption of the metre as a scientific unit of length: the forerunners and International prototype metre bar, while the three last paragraphs of the latter introduce the subsection Metrology and paradigm shift in physics containing the two subsections Wavelength definition and Speed of light definition. I already made the change as looking the result may be clearer than my confuse explainations. Charles Inigo (talk) 06:32, 11 October 2023 (UTC)
 * I moved the major part of the second paragraph of the section Metrology and paradigm shift in physics to introduce the subsection International prototype metre bar. Charles Inigo (talk) 06:48, 11 October 2023 (UTC)
 * I merged Metre into the article History of the metre using template:excerpt as suggested by @fgnievinski along with other adjustments of the article. Charles Inigo (talk) 08:05, 17 October 2023 (UTC)

You have it completely backward. The appropriate use of excerpt is to excerpt a few passages from a detailed article like History of the metre into a secton of a broader article, like Meter, that summarizes the detailed article. Jc3s5h (talk) 13:55, 17 October 2023 (UTC)
 * I dont think it changes anything to the result to know where the excerpt is from. What is important is that the content can be excerpted from one article into the other. Furthermore, it has not been proposed to merge the article History of the metre into the broader article Metre, but to merge the section History of definition of the article Metre into the more detailed article History of the metre. This is what has been done taking into account several issues which have been discussed. Charles Inigo (talk) 13:49, 21 October 2023 (UTC)
 * For practical reasons and trying to be as concise as possible, I found it easyer to work first on the article Metre, then make excerpts into the article History of the metre and choose among the preexisting material of this article what deserved be kept as additional informations. Charles Inigo (talk) 09:23, 22 October 2023 (UTC)

International prototype metre bar
Our section on the international prototype metre bar is instead a detailed account of developments in geodesy. It included a digression on the nature of error which I removed, only to see it reinserted further up. One of its images dominates the whole article, possibly shown at great size to accommodate what may be Wikipedia's longest caption. Much is irrelevant to the metre or provided in far too much detail; one example somewhat at random, is the formation of the International Latitude Service, complete with its head office's location, which came six years after the creation of the prototype bar and had no effect upon it.

Some of this material may also be found in History of the metre and Carlos Ibáñez e Ibáñez de Ibero, and possibly elsewhere, but duplicate or not, it's excessive here. I believe some serious copy-editing and trimming is required, but that will be difficult if any deletions are simply reinstated in different paragraphs. NebY (talk) 17:51, 27 August 2023 (UTC)


 * The gigantic image and gigantic description is frankly an embarrassment. It looks ridiculous, and the excessive details belong either in the article or elsewhere. Concur with user NebY. cheers. anastrophe, an editor he is. 20:16, 27 August 2023 (UTC)


 * Thank you for sharing your opinions. The material in the article has been substantially reduced. Charles Inigo (talk) 06:44, 28 August 2023 (UTC)


 * I think the digression on the nature of error was important there for the same reason why I mentionned polar motion, because even if polar motion had not been exensively studied when the length of the metre was determined this was a source of error, as was vertical deflection which had not been defined as such at that time. Charles Inigo (talk) 13:33, 28 August 2023 (UTC)


 * I have a remark about the text you reverted :
 * "In the second half of the 19th century, the creation of the Geodetic Association marked the adoption of new scientific methods. The association proposed the application in the field of geodetic observations of the method of least squares, discovered simultaneously by Legendre and Gauss, then developed by the latter. At that time, statisticians knew that scientific observations are marred by two distinct types of errors, systematic errors on the one hand, and random errors, on the other hand. The effects of the latter can be mitigated by the least-squares method. Systematic errors on the contrary must be carefully avoided, because they arise from one or more causes that constantly act in the same way and have the effect of always altering the result of the experiment in the same direction. They therefore deprive of any value the observations that they impinge. As science progresses, the causes of errors are sought out, studied, their laws discovered. These errors pass from the class of random errors into that of systematic errors. The ability of the observer consists in discovering the greatest possible number of systematic errors in order to be able, once he has become acquainted with their laws, to free his results from them using a method or appropriate corrections. The progress of metrology combined with those of gravimetry through improvement of Kater's pendulum led to a new era of geodesy. If precision metrology had needed the help of geodesy, the latter could not continue to prosper without the help of metrology. It was then necessary to define a single unit to express all the measurements of terrestrial arcs and all determinations of the force of gravity by the mean of pendulum".
 * This is not just a digression on the nature of errors. It explains why the BIPM was founded. The scientific reason of BIPM foundation was the efforts to take in account temperature errors which could not simply be corrected by the least squares. It means that European scientists knew that the metre was to short, but that as statisticians they knew that they needed a decimal unit and an institution where standards used in the field could be compared at controlled temperatures. Charles Inigo (talk) 16:06, 28 August 2023 (UTC)
 * There are several issues with that passage. It hardly needs saying, in this day and age, that scientists wish to avoid error; there is no need for a prolix lecture on it. It is marked by dramatic phrasing and rhetorical flourishes that wander into unsourced exaggeration and are not in good English either (outstandingly, "They therefore deprive of any value the observations that they impinge", but in many ways that is characteristic of the whole passage). It remains focused on geodesy rather than geodesy's contribution to the metre. Your one-sentence summary "European scientists knew that the metre was to short, but that as statisticians they knew that they needed a decimal unit and an institution where standards used in the field could be compared at controlled temperatures" is closer to what we need; not yet appropriate, but closer.
 * There are similar and other problems with the whole section. You don't have to fix them yourself; other editors may respond to the tag I've restored, and I'll tackle it when I can dedicate the time to it, in a couple of days or so. NebY (talk) 17:25, 28 August 2023 (UTC)
 * Thank you for your help. As you probably gessed English is not my native language. I hope you will find a way to rephrase my ideas. I think the creation of the BIPM and the international prototypes were focused on geodesy's need rather than contribution of geodesy to the metre which was the project of the French Academy of Science in the end of 18th century. In the second half of the 19th century the idea was to find ways to discover the greatest possible source of systematic errors and free the results of the observations from them using a method or appropriate correction (for instance compare at controlled temperatures the standards in order to define their coefficient of expansion, determine the personal equation of the astronomers or to measure the longitude of the extremity of arcs of parallel thanks to the invention of telegraphy). That's the reason why I inserted both the images of a geodetic standard and of a gravimeter with informations on the methods used to correct systematic errors of these measuring instruments. Charles Inigo (talk) 18:56, 28 August 2023 (UTC)
 * Hello, I just wanted to add to this discussion that I inverted some paragraphs of the section Meridional definition with some paragraphs of the section International prototype metre bar of the article Metre in order to restaure chronologic order and to keep all the discussion on the creation of the first scientific associations in the section International prototype metre. I suppressed a citation by Cajori and replaced it by another on Hassler apparatus and restored a paragraph on the Ibáñez apparatus as was suggested by Anastrophe. Charles Inigo (talk) 13:27, 1 September 2023 (UTC)
 * Moving details around doesn't deal with the essential problem of too much detail expressed in somewhat impenetrable prose. I'll restore the tage so that other editors may assist; please don't remove it again. NebY (talk) 17:56, 2 September 2023 (UTC)
 * Ok. I whish you the best. Charles Inigo (talk) 21:22, 2 September 2023 (UTC)

Mnemonic ("three threes")
I removed the mnemonic ("1 metre is nearly equivalent to 3feet $3 3/8$inches."), and put it back. Nothing to make a big fuss about, but fwiw, here is why I removed it: Imaginatorium (talk) 14:05, 4 September 2023 (UTC)
 * It is not encyclopedic information, rather it is a "how-to" hint for learners. It is possible that in fact this is/was a widely taught guideline in some circumstances, in which case there should be a cited reference to this as a social phenomenon.
 * It is not very good: actually you have to remember not just "three 3s", but "3 3 3 8", otherwise you might misremember it as 3' 3 3/4" or 3' 3 3/16".
 * It is not actually much use: back-of-the-envelope calculations these days are done with calculators, but you would need a calculator supporting mixed-base arithmetic and binary fractions (as in the problems I did at primary school: divide 3' 3 3/4" by 7).
 * You only need to remember "one inch = 2.54 cm" (three digits, again), and you can calculate anything precisely correctly using a normal calculator.


 * The points Imaginatorium makes about calculators being ubiquitous are valid. But if someone in the US (and perhaps the Canadian building trades?) were faced with measuring out a length stated as a whole number of meters and only had a customary tape measure, the mnemonic would be useful. I'm not sure if that's common enough to be worth mentioning. Jc3s5h (talk) 14:12, 4 September 2023 (UTC)
 * They also need to still have good mental arithmetic (despite calculators) to convert 3 or 4 metres to feet and inches with this mnemonic, and we already have a narrow audience anyway (US building trade, tape in customary units only being used to measure a round number of metres). NebY (talk) 15:33, 4 September 2023 (UTC)
 * In addition to Imaginatorium's points, that mnemonic was added in 2010 with the edit summary "created a simple mnemonic; 1 meter is 3 feet, 3 and 3/8 inches" and as a reference . That was changed to with the edit summary "well-known", presumably referring to Metrication in the United Kingdom in the 1970s (going by the editor's userpage, anyway). That ref was tagged where later in 2010 and removed in 2019. In short, the statement has never had a source for the mnemonic's existence, let alone the statements that it's simple and assists; all we have is an editor's claim that it was publicised about fifty years ago and is, or was, well-known somewhere. NebY (talk) 16:05, 4 September 2023 (UTC)


 * I restored the paragraph because I think approximations are in principle knowledge worth including in an encyclopedia. The classic example is the various approximations of pi (22/7 etc.), which have considerable historical as well as practical significance. Generally I am also sympathetic to including useful well-known mnemonics in an article. Yes they are "how to", but they are also useful to readers, and often even a bit fun! But I agree now that the case for inclusion of this particular mnemonic is questionable. We don't need a reference to support its truth ("sky is blue"), but it would indeed be desirable to be able to show that it is or was in use rather than made up afresh by an editor. On the question of whether this mnemonic is useful, yes I think it is even in these days of mobile phones. We all know that a metre is a bit more than a yard, but this does indicate how much more in a handy, memorable way; it's really not as convenient to have to multiply 2.54 by 36 to work that out even if a mobile phone is within reach. So, if someone can find a reference to its use (which I couldn't), I would vote to keep it. JMCHutchinson (talk) 17:15, 4 September 2023 (UTC)
 * Much as pi's historic and easily remembered approximation 22/7, plus calculators, left little demand for mnemonics for pi, I suspect that the approximation 3' 3", the precise 25.4 and tape measures in feet and metres left little room for this mnemonic. Many are created, few catch on. NebY (talk) 10:26, 5 September 2023 (UTC)

Relevance of Danish, Dutch, German, Norwegian, and Swedish spellings?
I removed the sentence: But it was restored. There are a few reasons why I disagree with it: What value is this sentence supposed to be adding to the article? -- DeFacto (talk). 14:13, 21 December 2023 (UTC)
 * I cannot see how the spellings used in these five foreign languages is relevant to this English-language article.
 * It fails WP:SYNTH as that specific selection of languages isn't supported by a secondary source as notable for their use of the 'meter', spelling.
 * It fails WP:DUE WEIGHT as it is being presented as an example of something that has no apparent relevance to the article.
 * It fails WP:NPOV as it only shows languages that use the 'meter' spelling, and not the 'metre' spelling, or any other spelling.
 * It doesn't explain why that subset of just two of 'Germanic languages' and just three of the 'north Germanic languages' was cherry-picked and used.


 * I don't feel as strongly as user:DeFacto, but I found the sentence of interest and I think that at least some of their arguments are going over the top rather. In an article about a unit used internationally it certainly seems relevant to say how it is written in other languages besides English. One might justify the choice of these Germanic languages for special attention by their close relatedness to English (English is also a West Germanic language); this comparison reveals that the English spelling is rather unusual. I don't think we would normally need a source to justify the choice of particular illustrative examples amongst the Germanic languages; it would be natural to choose some of the more familiar languages in each category as examples. Where I would agree, is that it would be more balanced to mention in addition how metre is spelled in some other important languages besides these, for instance in the Romance languages. My impression is that meter is the much commoner spelling in other languages, which would be worth adding. JMCHutchinson (talk) 15:34, 21 December 2023 (UTC)
 * I agree with @Jmchutchinson. But the core reason I reverted the change the first time was the edit summary used in removing it "this is the English Wikipedia though, how it is spelt in other languages is irrelevant here". The English Wikipedia is written for English-language readers, but there is no reason to limit the content to English-language words. The line of reasoning comes across as some kind of culture war language.
 * I agree that the scholarship is poor and to be honest if that had been the reason to delete it I would not have lifted a finger.
 * (This Talk page spills a lot of words over swapping two letters!) Johnjbarton (talk) 15:53, 21 December 2023 (UTC)
 * 'Culture war language"? I'm not sure how questioning the reasoning behind the introduction of those specific foreign spellings could be interpreted as that. -- DeFacto (talk). 18:23, 21 December 2023 (UTC)
 * You continue to use this flawed cultural logic. "Foreign spellings"? This is not the "Nation of England" Wikipedia; these spelling are not "foreign" and thus not a reason to remove them. The sentence is simply information -- written in the English language for English readers -- about other languages. Johnjbarton (talk) 19:01, 21 December 2023 (UTC)
 * Ah, perhaps we are 'separated by a common language'. I apologise if my language isn't clear to you, perhaps I should have said 'non-English spellings". The point still stands though, they still add nothing to the article without the reasoning behind their inclusion being made clear.
 * "Nation of England"? No, just English-language Wikipedia. The use of non-English words in an English-language article needs to be justified, and I cannot yet see any justification. -- DeFacto (talk). 19:28, 21 December 2023 (UTC)
 * As the person who restored this bit, I feel I should comment. I suspect that 'meter', or something extremely like it, will be the spelling in every extant Germanic language, except English. The fact that American (if I, being English, may be so bold as to use this less confusing term) follows the Germanic tradition is because (OR alert!) American is "translated German" much more than actual English, and this would be why Webster wanted to switch to German spelling, away from the long French influence on English.
 * So I think this comment is interesting, useful, and backed by evidence (sorry, m'lud, the other thing), and it would be a pity to remove it. But a bigger scale comment might point out how worldwide, languages have to do something with the impossibility of French pronunciation, and they are fairly evenly split (see metre) between 'met*r' and 'metr*'; eg ru is "метр, but Makedonian is "метар". The Romance languages are solidly 'metro' etc. Imaginatorium (talk) 16:13, 21 December 2023 (UTC)
 * Small point - in the introductory section on Orthography of A Compendious Dictionary of the English Language, Webster describes it thus:
 * The present practice is not only contrary to the general uniformity observable in words of this class, but is inconsistent with itself; for Peter, a proper name, is always written in the English manner. Metre also retains its French spelling, while the same word in composition, as in diameter, barometer, and thermometer, is conformed to the English orthography. Such palpable inconsistencies and preposterous anomalies do no honor to English literature, but very much perplex the student, and offend the man of taste.
 * He does write:
 * When therefore a French, or a German word is introduced into English, the letters should be translated—and the true sounds of the foreign words expressed in English characters of correspondent powers.
 * But he doesn't, I think, suggest switching to German spelling. NebY (talk) 16:32, 21 December 2023 (UTC)
 * If we think there are valid reasons for including these spellings, shouldn't the reasoning behind their inclusion be explained in that section of the article then? Along with reliable secondary sources supporting that reasoning, of course. -- DeFacto (talk). 18:28, 21 December 2023 (UTC)
 * We don't do that in other articles; why here? Wikipedia is not a dictionary, let alone a translation dictionary. We don't provide the Germanic words for London, Rome, Athens or New York. We don't list kilogramm, kilogramo, chilogramma or quilograma, nor Kilowattstunde, kilovatio-hora or kilowattuur. We don't provide translations for other international units either; Knot (unit) doesn't mention nœud or knoop, and though Fahrenheit was Polish-born with German ancestry, we mention neither the stopień Fahrenheita nor the Grad Fahrenheit. As for reveals that the English spelling is unusual, that surely requires direct sources, otherwise we're committing WP:SYNTH, and even if true is somewhat trivial; there is a great deal of variation among all the languages of the world, and virtually all spellings, even of "common" words, are in the minority. NebY (talk) 16:15, 21 December 2023 (UTC)
 * I think your points are valid. I possibly (over)reacted to the "cherry picking" expression, which just seems to me to be wrong. I certainly don't think anything "reveals that the English spelling is unusual". The Americans say "senner", spellt 'center', the English say "center", spellt 'centre', which the French pronounce differently. Imaginatorium (talk) 16:30, 21 December 2023 (UTC)
 * Given that only five other languages were included, that they all used the same spelling as US English, and that there was no explanation, rationale, or context given for mentioning just those five left me with the impression that they were cherry-picked, but I could not imagine why. -- DeFacto (talk). 18:33, 21 December 2023 (UTC)


 * Our articles on London, Rome and Athens indeed do not mention the German versions, but they all mention some other-language versions of these names, particularly in the context of etymology. If related (i.e. Germanic) languages all use a different form, it strongly implies that English has changed the form, I guess under the influence of French. That is what I meant when I wrote above that the information on Germanic languages showed that English was unusual. Unless we can find a reference, that conclusion might be criticised as original research, but that doesn't mean we can't present relevant information that allows others to draw their own conclusions. JMCHutchinson (talk) 17:48, 21 December 2023 (UTC)
 * We have a good, referenced description of the etymology in Metre. The unit was invented in France and named in French, using an existing French word derived from Latin and before that, Greek (the noun μέτρον and its associated forms are very common in ancient Greek). Why do you think the name of the unit might be Germanic and that English has changed the form, I guess under the influence of French? Do you have Germanic dictionaries indicating some other etymology, and reject the etymology given in the Oxford English Dictionary as cited and in many other dictionaries? Or do you think that we should, by presenting Germanic words, mislead our readers into draw[ing] their own conclusions about etymology? NebY (talk) 18:38, 21 December 2023 (UTC)
 * You are right, and I was being somewhat stupid. Nevertheless there is a more subtle point to be made. The word "meter" (meaning an apparatus to measure something) was around in both English and other German languages already in the 17th century; it is noteworthy that later the other German languages retained that spelling for the unit of length, whereas the English did not. JMCHutchinson (talk) 19:48, 21 December 2023 (UTC)
 * Ah good, I was worried! But no, we shouldn't try to imply, however subtly, that meter is the proper Germanic word, English was deviant in using metre and Webster corrected that. As well as breaching WP:SYNTH, it would misrepresent the languages. Most English vocabulary is not Germanic; it is and long has been mostly derived from French, Latin and (especially for neologisms in science, technology and academic disciplines) ancient Greek (I'm italicising some examples, hope it's not too distracting). This is one of the great strengths and glories of English and a stark difference from, say, German's long compounds. It was thus completely normal for English, which already had both meter (as measuring device  person ) and metre (in verse), to import metre from French. It left English with only a trivial ambiguity (verse and distance are very different domains, easily distinguished). Webster's rationalisation left a greater one in AmEng but you'll notice, in the quotation above, that he did not argue that it was more appropriate to English's Germanic nature. In short, it's commonplace, not noteworthy that English used the original spelling of the name of the unit, rather than imposing a Germanic one as German did. NebY (talk) 15:57, 22 December 2023 (UTC)
 * Very eloquently put, thanks . I think that explains very clearly why those non-English terms are irrelevant, SYNTH, and non-NPOV. -- DeFacto (talk). 17:09, 22 December 2023 (UTC)
 * I too found NebY's account eloquent and interesting. But, opposite to your conclusion, it made me hope that the contrast with other Germanic languages would be retained, and explained. JMCHutchinson (talk) 22:11, 22 December 2023 (UTC)
 * The presumption that vocabulary formation would be the same in English and German is yours; we should not burden this article's readers with a discussion of that error. NebY (talk) 17:31, 23 December 2023 (UTC)
 * If you have a reference for these claims, that information would be a great addition to the article. Johnjbarton (talk) 17:47, 22 December 2023 (UTC)
 * Mentioning other-language versions where they are relevant to the etymology of the word in question would be expected, but, as in this case, mentioning them where they have no apparent relation to the origin or history of the word in question would not. -- DeFacto (talk). 18:42, 21 December 2023 (UTC)


 * I'm afraid the mention of other-language spellings does not even seem to relate to the spelling in English. If we have a sourced etymology, fine.  Simply  providing a contrast with other languages that use similiar alphabets strikes me as being incidental, and as suggested by the added template, complete synthesis in WP's voice.  If it is kept, it belongs in a subsection entitled "In other languages", since it does not talk about the English etymology.  Placed as it is, it creates the distinct impression that it is intended to contrast them, which is undeniable synthesis.  I would prefer to just remove it.  —Quondum 21:02, 22 December 2023 (UTC)


 * I found a source in English (The Century Dictionary p. 3739) mentionning both spelling meter and metre and also the use in Dutch, German, Swedish and Danish of the meter spelling. The source also mentions the French spelling mètre and the Spanish, Portugese and Italian spelling metro. I note that the disputed sentence follows the mention of the use of the meter spelling in the United States. The question this raises is why the American spelling is closer to German spelling than the United Kingdom spelling ? A possible explaination is that the foundation of the US Coast Survey and the seminal work of Ferdinand Rudolph Hassler, a Swiss born geodesist originally from Aargau in German-speaking Switzerland, and Charles Sanders Peirce « helped remove American metrology from under the British shadow and usher in an American tradition », as wrote Robert P. Crease in Physics Today 62 (12), 39-44 (2009), through collaboration with the German Imperial Standards Office, International Association of Geodesy, and later the BIPM. Among the first American meter standards at least three were introduced to the United States from European German-speaking countries according to Victor F. Lenzen in PROC. AMER. PHIL. SOC. VOL 109, NO. 1, 1965. Charles Inigo (talk) 17:55, 24 December 2023 (UTC)
 * "A possible explaination": fine for general discussion here but in the article that would violate WP:SYNTH. A far more likely explanation is that Webster wanted spelling to match pronunciation - same for "centre"→"center", "colour"→"color", etc. I don't believe that Hasller affected these words as well, and therefore is less likely to have strongly affected "metre"→"meter". Of course, I'm just an armchair etymologist.  Stepho  talk 01:35, 25 December 2023 (UTC)
 * Hello, I am glad to read you on Christmas day. Thank you for acknowledging my participation in this general discussion. When I was in class in England, my classmates were amazed by my understanding of supposedly complicated English words despite my relatively poor English. This was easily explained by the fact that these words were of French etymology as well as the word metre (unit of length). The source I mentioned also indicates that the word meter or metre (not in sense of a measure of length) was also formerly written meeter. Charles Inigo (talk) 08:11, 25 December 2023 (UTC)
 * I also noticed that English speakers have great difficulty pronouncing a silent e. This probably represented an obstacle to the adoption of the French pronunciation in English, alongside the fact that the word already existed in English with other meanings. Charles Inigo (talk) 11:27, 28 December 2023 (UTC)
 * Another point is that the French word mètre is a scientific word corresponding to the unit of length of the International System of Units. Despite the fact that English has become the dominant language in scientific literature with a strong predominence of American scientific publications, the official language of the BIPM’s plublications is French. These publications also provide an English translation in which the French word mètre is translated metre.
 * Any explanation has to take into account that we had words such as both metre and meter, and centre from at least 1755. See Johnston's 1755 dictionary https://johnsonsdictionaryonline.com/views/search.php?term=metre
 * The simple explanation is that England's nobility spoke French for a long time (since being conquered by the Normans in 1066), so French words and French spelling crept into the English language.
 * But beware of WP:SYNTH from armchair etymologists such as you and me. Find a reference that says it explicitly.  Stepho  talk 14:20, 28 December 2023 (UTC)

ΜΕΤΡΩ ΧΡΩ
Does anyone have a source on this being a Pittacus quotation? Apart from being -wouldn't you say- necessary, a source might also help with making sense of the Greek (if for example this is dative + imperative, where is the iota of the former? unless this is some weird aeolic form or simply an anachronistic omission). Thanatos|talk|contributions 17:20, 10 March 2024 (UTC)


 * Perhaps this helps. https://www.thefreelibrary.com/Ecumenical+Theology+of+Hope+for+the+Common+Oikos+and+the+Greed+Line+as...-a0577908341
 * I think the Free Library is not a valid source for us but perhaps it can be used as a springboard to find something better.  Stepho  talk 05:16, 11 March 2024 (UTC)
 * I'm beginning to think that this is made up, that someone, looking for gravitas, having consulted some friendly hellenist coined μέτρῳ χρῶ to put on the seal cutting out the iota subscript for simplicity and then (someone else subsequently?!?!) attributed it to Pittakos. PS Pittakos' τοῖς ἐπιτηδείοις χρῶ (see e.g. Diels H., Die Fragmente der Vorsokratiker, 1960, p60) might have served either as an inspiration for the former or as close enough quotation for the latter. Thanatos|talk|contributions 23:16, 11 March 2024 (UTC)