Talk:Inch

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Untitled[edit]

Do I see this wrong, or are the French and Italian words for thumb also the same as the word for inch, like in Dutch?

Another thing, that one can read between the lines but isn't stated, is that probably the inch and the foot (the one a thumb the other a foot) were originally not related but adapted so that one is exactly 12 times the other (a dozen; a number that used to play the role of the number 10 these days). DirkvdM 07:11, 13 August 2005 (UTC)[reply]

Inch, Foot, Yard and the Body[edit]

As we know, the Metric System defined its length by defining the distance from the North Pole, through Paris to the Equator to be 10,000km. Not surprisingly, its lengths do not correlate at all well to the human body (so many people find it more natural to express a person's height in feet and inches. Although Australia has been 'metric' for about 40 years now, the police always give the height of a wanted suspect in feet and inches).

Whatever the origins of inch, foot, yard (and the precise corresponding lengths seem to have varied in different cultures at different times), they seem to be definitely related to proportions within the human body. I'm male of average build, and 5feet 11 inches tall (1.78m). Starting from the palm of my hand, the distance between the 2nd and 3rd joints of my middle finger is surprisingly close to one inch.

The distance from the crease of my elbow to the joint at the base of my thumb is also surprisingly close to one foot. When I'm walking quite naturally (not striding out or hurrying), the distance between where my left foot touches the ground each time is quite close to one yard (or the right foot, of course).

These measurements would have to be standardised within a society. However, a person can measure something reasonably accurately without a tape measure, just using their own body. (DaveNed88 (talk) 04:06, 30 March 2010 (UTC))[reply]

Inch or Thumb[edit]

DirkvdM

Yes your are correct and these are now included in the main page. The French for inch and thumb is 'pouce'. The Italian for inch and thumb is pollice. In fact the Latin word for thumb is pollex.

Now the section of the main page on the Historical origin does mention this coincidence but then goes on to say that the inch probably did not derive from the width of the thumb, despite the fact that it also says that in about 1150 King David I of Scotland defined the inch "as the width of an average man's thumb at the base of the nail, even including the requirement to calculate the average of a small, a medium, and a large man's measures". Now since the subdivision of the foot into 12 inches is very heavily supported as deriving from the Roman division of the 'Pes' into 12 unciae, that the Latin for thumb is pollex and the majority of European languages had the same or very similar word for thumb and inch, it would difficult to claim there was no connection with the Romans. As to the actual size of the inch, in the reference to King David's edict, the text goes on to "account for the much larger length later called an inch". Why should King David's inch be that much different to today's? If I place my thumb on a foot ruler, it measures exactly 1 inch at the base of the nail as close as I can see, and I don't consider my thumb to be either overlay large or unusually small. So who is suggesting the inch as defined by King David was smaller than the modern version?

Is it more likely that the Roman format of the Pes and the uncia continued in use through medieval times down to modern eras with only minor alteration in their sizes, and that the overwhelming occurrence of the use of the same word for thumb and inch was also a descendent of the Roman practice. Where else would so many languages get the same basic word for the same measure if not from the original word pollex? In the same way that the introduction of the duodecimal/vigesimal [[1]system of money] promulgated by first Pippin and then his son Charlemagne was adopted throughout Europe, is it not possible that this also included the same format, (if not the same sizes) of measures that were also distributed throughout the same area.

It would appear to me that more investigation needs to be done into the history of these measures before rejecting out of hand one specific origin for the inch. What is more likely is that the inch was in use for many centuries as a defined fraction of the foot, but that both the inch and the foot were redefined in terms of their length at different stages, and that they incorporated or were included into other pre-existing systems. That the modern foot so closely matches the Roman foot is a very clear pointer to its and the inches robustness and usefulness over the last 2000 years. If they had died out or had changed more dramatically, this would have illustrated their lack of functionality. The opposite is the only conclusion. —Preceding unsigned comment added by Ruthe (talkcontribs) 22:52, 14 December 2008 (UTC)[reply]

I just put an OR? tag on the part about the thumb and inch. Etymology is a tricky subject. That's why they have experts who study that stuff. At the very least, someone should provide some references to back up the claim, preferably accompanied by criticism from the opposite point of view. Zyxwv99 (talk) 15:08, 27 February 2012 (UTC)[reply]

Abbreviation[edit]

Shouldn't there be a tie-in with the use of caliber (.22, .38, etc)?

What is the correct abbreviation? in?

How do I say square inch? in²? --Abdull 12:41, 16 September 2005 (UTC) 208.126.51.37 (talk)[reply]

Yes. Yes. Gene Nygaard 13:26, 16 September 2005 (UTC)[reply]
in. is an older form of jbvi;abbreviation that can be found. It follows the Enlgish practice that the full stop replaces the missing part of the word eg "Capt." "Maj."GraemeLeggett 15:05, 26 January 2006 (UTC)[reply]

Infobox[edit]

I made an infobox; see its talk page for discussion. -Branddobbe 07:32, 18 October 2005 (UTC)[reply]


Non-alphabetic symbols[edit]

I am from Germany and i read about a girl who is 5'3" tall. So is she 5 foot and 3 inch tall?

Yes, she is 1,60 m. If you had read this article or Zoll you should have known. Christoph Päper

actual sizes of other inches.[edit]

ok so the modern international inch (and it seems from the text the old canadian inch) is exactly 2.54 cm but what about the other inches? how different were they?Plugwash 20:38, 13 May 2006 (UTC)[reply]

See Systems_of_measurement#Medieval_European_measurements and compare the links. 惑乱 分からん 01:33, 11 September 2006 (UTC)[reply]
I agree. Since this is the English-language Wikipedia we should, at the least, have the precise lengths (and names) of inches used in English-speaking countries, going back at least as far as living memory. For example, there are people alive today who still remember the Enfield inch, the pre-1963 imperial inch, the pre-1959 US inch, etc. And don't just tell people to look under Medieval Measurements: we're that that old. Zyxwv99 (talk) 16:47, 11 January 2012 (UTC)[reply]

Swedish decimal inch[edit]

Is this still used in land surveying? I would have guessed Sweden would survey in Metric by today... 惑乱 分からん 01:33, 11 September 2006 (UTC)[reply]

I've never heard of such a thing, but then again I dont work in land surveying. Inches/thumbs are used in construction though. // Lars
Late reply, but don't construction workers use the 2.54cm inch? 惑乱 分からん * \)/ (\ (< \) (2 /) /)/ * (talk) 23:12, 12 June 2008 (UTC)[reply]
Yes, most scales in Sweden (and probably in some other metric-countries) have cm on one side and 2.52 cm inches (swedish for inches is "thumbs") on the other. Both are used, depending on which components you use and so on. Ran4 (talk) 15:14, 26 July 2008 (UTC)[reply]
2.52? You're not referring to the international inch (2.54 cm)? And, yeah, I have seen rulers etc with both cm's and (int.) inches, as well as old yardstick with the "working inch", but I figured that these Swedish inches basically have gone deprecated now. 惑乱 Wakuran (talk) 23:09, 14 August 2008 (UTC)[reply]

That was probably a typo for 2.54 cm. From teh Wiki article on Swedish "Tum" (inches): tum – Thumb (inch), after 1863 1/10 fot, 2.96 cm. Before that, 1/12 fot or 2.474 cm. So, to hazard a guess, today they probably just use dual international inch/cm tapes that are commercially available, unless they are working with legacy parts.Surveyor792 (talk) 02:51, 13 October 2013 (UTC)[reply]

Er, this was a discussion from 2008. There doesn't seem to be any mention of a 'Swedish inch' in the article any more.  Stepho  talk  07:33, 13 October 2013 (UTC)[reply]

Yeah, I can read, both the date, and the Swedish inch and foot mentioned in the table at the end of the articleSurveyor792 (talk) 05:20, 20 October 2013 (UTC)[reply]

I can only find two mentions of the Swedish inch - once in the etymology section about the word (with no mention of actual length) and once in the image near the etymology section which shows various international inch lengths side-by-side (with no decimal lengths given and is illegible until clicked on). I see no table at the end of the article. I see no mention at all of the Swedish foot.  Stepho  talk  22:39, 20 October 2013 (UTC)[reply]

Sub-unit of an inch[edit]

What is the unit for sub-dividing an inch into 16 equal parts ?

Sixteenths of an inch, i.e. 1/16th [of an inch], 1/8th [which is really 2/16th], 3/16, etc. I don't think there is a formal name. It is not uncommon in tooling to see the inch fractionized into 64ths. MJCdetroit 15:46, 25 October 2006 (UTC)[reply]
There are some very obsolete units like the barleycorn - which is a third of an inch - but I don't think there is a 1/16th inch unit. SteveBaker 15:13, 15 May 2007 (UTC)[reply]
You're correct in that there is not a formal unit name. I should have been a little clearer by saying it is commonly fractionalized into smaller amounts. MJCdetroit 15:33, 15 May 2007 (UTC)[reply]

Personal height in Canada[edit]

In Canada, the trend has been shifting towards metres, as shown on a person's driver's license. [In referring to personal height]

Is there any truth to this? In my own personal experience, I have never heard an English speaking Canadian refer to their height in terms of metres. On Hockey Night in Canada, I have never heard a hockey player's height described in anything but feet and inches. In fairness, most of the Canadians I know are in Southwest Ontario. I don't know if it is different in other parts of English speaking Canada. —MJCdetroit 15:59, 25 October 2006 (UTC)[reply]

Official documents tend to be in metric, since the country is officially metric. However, many people are still familiar with the imperial system so the old units are commonly used. In Quebec, there is a slight tendency to prefer metric to imperial, as it has less to do with any British history. Michael Daly 20:10, 28 September 2007 (UTC)[reply]

Equivalence table[edit]

Maybe the table should be corrected so that 1 inch = 0.0254 m, so that it shows all the significant figures (except for the infinite zeros trailing behind) Knights who say ni 17:27, 7 November 2006 (UTC)[reply]

To have a list of three equivalent imperial units and one metric is rather biased. espescially since the term cm isn't the basis for the metric system. using either 0.0254m (as suggested above) or 25.4mm would be more appropriate (it's generally tidier to move in three powers of ten at a time) —Preceding unsigned comment added by 62.94.33.30 (talk) 15:55, 27 November 2008 (UTC)[reply]

The inch in metric units[edit]

The article states that "The United States and Canada each had their own, different, definition of the inch, defined in terms of metric units. The Canadian inch was defined to be equal to 25.4 millimetres." Therefore, is the old Canadian inch the current international inch? SteveSims 06:04, 27 November 2006 (UTC)[reply]

Yes, actually. Apparently scholars were working on the proposed international inch long before the official treaty was signed in July 1959. By then, Canada had long since switched over. California sometimes does this sort of thing on various issues, e.g., pollution controls for cars, etc. Zyxwv99 (talk) 00:03, 3 February 2012 (UTC)[reply]

Inch vs. Metric[edit]

I'm English and we learnt the metric system in school; centimetres and metres. It was oddd learnig feet and inches after moving to the U.S. And like Canada it seems, we brits measure height in feet and inches and often use 'miles' too.

prince 07:16, 19 December 2006 (UTC)[reply]


That makes no sense whatsoever! 84.13.162.0 (talk) 14:09, 7 January 2010 (UTC)[reply]

Measuring tape image caption[edit]

The caption below the image of the measuring tape says that the tape is capable of measuring down to "1/32th of an inch", but shouldn't this be "1/32nd of an inch"? A small detail i know, but 32th doesn't read very well at all. I've held off changing it though, just in case all inch subdivision fractions should use "th" JieBie 08:52, 7 February 2007 (UTC)[reply]

Fixed.--agr 14:04, 7 February 2007 (UTC)[reply]

Infobox[edit]

I don't like that the infobox shows decimal units for the number of inches in a foot/yard/mile. Those are approximations only - the true definitions (ie 1/12th ft, 1/32nd yd, etc) should be given. That is both clearer and more accurate (indeed infinitely accurate) - and would be far less confusing to someone coming from the metric world who truly wants to know how many inches there are in a yard or whatever. You could put the decimal expansions afterwards or something - but the way it is now sucks. SteveBaker 15:10, 15 May 2007 (UTC)[reply]

Vandalism or what?[edit]

I noticed that older version of the text are way much longer. What was the reason of massive deletions? Laudak 22:00, 12 October 2007 (UTC)[reply]

I agree that the older version is much better, and have restored it. I specifically came to the inch page hoping to find the historical origin of the unit which is in the older version and not in the newer one. David s graff (talk) 15:27, 22 May 2008 (UTC)[reply]

Age of 40[edit]

I assume that wikipedia articles aren't supposed to grow increasingly inaccurate with time by definition, so the phrase in the opening paragraph that people over the age of 40 in Australia probably should be changed to people born before a certain year/decade. I would change it myself, but have no source for the statistic except the article itself, and I don't want to try to figure out when that was added. 65.4.121.187 (talk) 23:39, 29 February 2008 (UTC)[reply]

Introduction[edit]

I don't see how knowing where in Canada they express hieght in feet and inches or metric adds any meaning to this article. I am removing it.Cpyder 14:52, 10 October 2008 (UTC) —Preceding unsigned comment added by Cpyder (talkcontribs)

Metric inch[edit]

"Additionally, the smallest size a human eye can differentiate is 0.01 inches, or 0.26 mm. This means that breaking the inch down into decimals is four times more precise than into millimeters, tenths of millimeters being too small to see." Now, I don't know about you, but I'd suggest that what the human eye can differentiate (I assume this is what is normally termed resolution) depends on how far away it is (since resolution is normally given by an angle). So I wouldn't know where 0.01 inches comes from. And the argument about tenths of millimetres is spurious at best, since the metric system isn't designed for that purpose. And plenty of stuff is smaller than 0.26 mm, but can still be measured. So what am I going to do about it? Suggest that the source given isn't a Reliable Source, being self-published and all. Any comments, before I get all bold and rip out that sentence? Jason A. Recliner (talk) 10:35, 10 November 2008 (UTC)[reply]

Removed:
Additionally, the smallest size a human eye can differentiate is 0.01 inches, or 0.26 mm. This means that breaking the inch down into decimals is four times more precise than into millimeters, tenths of millimeters being too small to see.[http://members.cox.net/mathmistakes/metrics.htm]
the smallest size a human eye can differentiate is much smaller. Human hair width is 0.07 mm (avg.).--79.111.217.50 (talk) 23:29, 24 November 2008 (UTC)[reply]
Although this is an old comment, just as a note. In machining, an experienced inspector or machinist can easily differentiate a 1 thou (.001" or .0254mm) mismatch in intersecting cuts or size in materials(relative to the total size of the piece) both by sight and feel. 74.7.239.26 (talk) 04:07, 29 May 2010 (UTC)[reply]

Cubic Inches - Article in the WP DE (german)[edit]

There is an article on the american V8 vehicle engines. Is anybody interested in a rough translation - to smoothen it afterwards? --80.145.233.235 (talk) 23:48, 2 January 2009 (UTC)[reply]

http://de.wikipedia.org/w/index.php?title=Cubic_Inches

Not 'widely used' in the UK[edit]

Apart from measuring your penis and the dimensions of a TV or computer screen when are inches used in the UK? Anybody under the age of 40 years old uses metric measurements for length except for the above exceptions just as imperial measurements of weight are only used for drug dealing by those under 40 years old, the fahrenheit system only used on really hot days to emphasise how hot it is and miles used for speed limits [yet shorter distances expressed in cm and metres as in "motorway service 100 metres"]. It is not the dominant system in the UK so shouldn't be described as 'widely used' in the opening paragraph. Thankfully the UK is using imperial measurements less and less leaving only the USA and Myanmar as the sole countries to use such a shitty system in day-to-day life instead of other systems.--217.203.136.221 (talk) 21:24, 8 July 2009 (UTC)[reply]

Sorry, I completely disagree (and I'm under 40). I've only rarely heard anyone measure long distances in the UK in anything other than miles, signs for shorter distances on the roads are always in yards, and virtually everyone I've ever heard measures their height in feet and inches. I've never heard fuel efficiency quoted in anything other than miles per gallon (despite fuel being sold by the litre). Thankfully there are still a very large number of people in the UK using the system that's worked perfectly well for a long time and aren't changing for the sake of change. Imperial units aren't used in technical work in the UK any more (apart from possibly in a few minor areas), but they usually seem to dominate in day to day speech, the only exception seems to be temperature and possibly short distances. Unfortunately I'm not aware of any study done one way or the other. Riedquat (talk) 12:09, 15 September 2009 (UTC)[reply]

Inch

I don't think the following sentence is accurate "The inch is usually the universal unit of measurement in the United States". Many companies use millimeters exclusively for design and production in the US. All motor vehicle manufacturers domestic and foreign design and build in millimeters. Caterpillar and John Deere also design and build in metric units so Universal is too strong, "common" would be a better adjective. Or reword the article that the inch is commonly used in public in the United States while the metric system is commonly used by large multinational corporations in the US. ~~metricmike~~ —Preceding unsigned comment added by Metricmike (talkcontribs) 13:04, 23 November 2009 (UTC)[reply]

It's untrue that ALL vehicle companies build in milimeters....Look at any truck specs(GM, Ford, Dodge..etc) and you will see wheel size listed in inches, torque listed in ft-lb, gasoline tank capacity in gallons, towing capacity listed in pounds and cargo capacity in cubic feet. — Preceding unsigned comment added by Eagle70ss (talkcontribs) 10:01, 15 February 2011 UTC

Communicating with customers is a different matter from designing and building. I believe what metricmike was claiming was that if one were to go into the design offices or the factory floor everything would be in metric. Customary units would be introduced by the people who write the owners manual, advertisements, website, etc. Jc3s5h (talk) 14:38, 15 February 2011 (UTC)[reply]

US is the only one country that is using inch. — Preceding unsigned comment added by Toroya (talkcontribs) 16:37, 23 April 2011 (UTC)[reply]

If so, then why can I find so many articles that use the inch at the Times of London website? Jc3s5h (talk) 18:22, 23 April 2011 (UTC)[reply]
The inch is included in the National Curriculum of the UK [2] and is widely used here despite metrication. All tyre radiuses here are measured in inches, for example. Dbfirs 18:24, 23 April 2011 (UTC)[reply]

Double Prime[edit]

It escapes me why the mention of a double prime used to denote inches requires a citation. It's such a ridiculously accepted standard that the notation is published on the first page of the Machinery's Handbook by Industrial Press Inc. Is the citation requirement there due to a distinction between the double prime and a double quote and which should be used to denote inches? —Preceding unsigned comment added by 24.23.38.220 (talk) 02:19, 14 February 2010 (UTC)[reply]

Expansion needed[edit]

I think this entry should have more coverage of the historical varieties of the inch, like the various German inches (e.g. the "Bavarian inch"). Unfortunately I don't have the knowledge and necessary languages to expand it myself. See Russian and German entries for more coverage. Ijon (talk) 15:12, 15 March 2010 (UTC)[reply]

Merger proposal[edit]

It has been proposed to merge inch (Scots) into this article.

  • Support. Encyclopedias treat closely related topics together in a single article. In this case it is not even clear that a separate Scottish inch ever existed. According to the relatively recent book Weights and Measures in Scotland by Connor and Simpson, the inch was very likely brought to Scotland from England in the early Middle Ages (I forgot the century, but I felt it was ridiculously early), when the burghs were founded as English trade posts. The idea of a Scottish inch slightly longer than an English inch apparently originated with antiquarians who tried to reconstruct a Scottish inch long after the Scottish units were abolished by force. None of the old ell standards had survived, but the case for one of them was mistaken for the standard itself. The antiquarians took the length of the case, which obviously was a millimetre or so longer (so that the standard itself would fit comfortably) and based their calculations on that.
Whether you believe this new, simple explanation for the slight difference, or subscribe to a genuinely different Scottish unit that happened to have exactly the same name and was 0.16% longer – in either case the story is best told in a single article. Hans Adler 21:16, 25 July 2010 (UTC)[reply]
  • Oppose - will result in yet another Anglocentric article with all the Scottish content completely subsumed.--MacRusgail (talk) 15:44, 2 August 2010 (UTC)[reply]
  • Support. There is not enough to say about the Scots inch (or any other national variety of the inch) to justify a separate article.
  • Oppose'. It goes with other Scottish weights and measures, and needs time to develop on its own. Fotaun (talk) 01:03, 20 August 2010 (UTC)[reply]
  • Support. This unit is now obviously the same as the modern inch, and has been for a long time. I support mentioning the Scottish inch in the article on Scottish weights and measures (in fact the content of this article could be preserved there), but many regions could claim their own version that was inaccurately measured, and we could end up with dozens of separate "inch" articles. Dbfirs 00:31, 9 November 2010 (UTC)[reply]
  • Support I concur with the above statement. Martinvl (talk) 15:23, 17 February 2011 (UTC)[reply]
  • Oppose --122.124.164.85 (talk) 11:10, 2 March 2011 (UTC)[reply]
  • Are people still interested in this? Anyway, I agree it doesn't deserve its own article, but I'd rather it was merged into obsolete Scottish units of measurement than here. This page could become very big if it was to include details of all the types of inch ever used. A. di M.plédréachtaí 15:55, 6 July 2011 (UTC)[reply]
  • Support. As per the support comments made above. Also, the "Oppose" comments are not following WP rules.
eg 1. "will result in yet another Anglocentric article with all the Scottish content completely subsumed" — rubbish, MOST of this text can fit onto the main page without compromising validity.
eg 2. "It goes with other (Obsolete) Scottish weights and measures, and needs time to develop on its own" — actually the link on that page can simply be altered to point to the section on the main page instead; nothing to do with any extra 'development'.
eg 3. "Anyway, I agree it doesn't deserve its own article, but I'd rather it was merged into obsolete Scottish units of measurement than here. This page could become very big if it was to include details of all the types of inch ever used." – as per eg 2, plus the length of the main page is no where near being a problem.
...let's also keep the nationalism out of WP fact listings. Jimthing (talk) 10:36, 4 August 2011 (UTC)[reply]
Done. Completed merge as per votes count, invalid oppositions, and WP rules. Jimthing (talk) 11:03, 4 August 2011 (UTC)[reply]

Usage in Canada[edit]

I distinctly remember earlier versions of this article mentioning that the inch is still widely used in Canada. It appears some still cannot come to terms with the fact that Canada OFFICIALLY allows BOTH the metric and Canadian imperial systems to be used (http://laws-lois.justice.gc.ca/eng/acts/W-6/page-14.html). Virtually all construction in Canada is done using imperial measurements (inches), virtually all cooking in Canada is done using imperial measurements (pan size, thickness of butter, space between cookies, for example, are given in inches), height is ALWAYS given in feet and inches, and railways have escaped metrication entirely, etc. It is important to note that even IF--and this is a big IF--the metric centimetre is given preference over the imperial inch, the fact of the matter is; inches are still LEGALLY used in Canada. I am amending the article to make note of this. 173.180.210.51 (talk) 22:46, 2 February 2012 (UTC)[reply]


Regarding the above talk comment. http://laws-lois.justice.gc.ca/eng/acts/W-6/page-14.html link is broken.

http://laws-lois.justice.gc.ca/PDF/W-6.pdf as of 9 Jan 2018 is a fresh link. This document gives reference definitions of Metric and Imperial units and state that trade must be done in one of those systems: "Use of Units of Measurement. Use of units of measurement 7

 No person shall, in trade, use or provide for the use of

a unit of measurement unless (a)

 that unit of measurement is set out and defined in

Schedule I or II; or (b)

 the use of that unit of measurement is authorized

by the regulations. 1970-71-72, c. 36, s. 7"

Schedule I and II are: "SCHEDULE I (Section 4) Units Based on the International System of Units"

"SCHEDULE II (Section 4) Canadian Units of Measurement"

That being said, section 4 clearly states: "Units of Measurement Basis for units of measurement 4 (1)

 All units of measurement used in Canada shall be

determined on the basis of the International System of Units established by the General Conference of Weights and Measures." "Basic, supplementary and derived units (2)

 The basic, supplementary and derived units of mea-

surement for use in Canada and the symbols therefor are as set out and defined in Parts I, II and III of Schedule I, respectively." "Customary units (3)

 In addition to the units of measurement otherwise

referred to in this section, the customary units of mea- surement and the symbols therefor as set out and defined in Part IV of Schedule I may be used in Canada, which units of measurement are commonly used with the Inter- national System of Units."

These all point to metric use only. But then it becomes confusing to me since sub-paragraph 5 says: "Canadian units (5)

 The Canadian units of measurement are as set out

and defined in Schedule II, and the symbols and abbrevi- ations therefor are as added pursuant to subparagraph 6 ( 1 )(b)(ii). 1970-71-72, c. 36, s. 4." Where Subparagraph 6 "Amendments to Schedules I and II Modifications 6 (1)

 The Governor in Council may by order

(a)

 amend Schedule I by adding to or deleting from

Part I, II, III, IV or V thereof any basic, supplemen- tary, derived or customary unit of measurement or any prefix therefor, together with its symbol and defini- tion; or (b)

 amend Schedule II

(i)

 by  adding  thereto  or  deleting  therefrom  any

Canadian unit of measurement, together with its definition, (ii)

 by adding thereto a symbol or an abbreviation

for any Canadian unit of measurement, or (iii)

 by deleting therefrom any symbol or abbrevia-

tion referred to in subparagraph (ii)."

This all seems to me to say: Metric is the basis for all measures, even older imperial measures (Note the "yard" is defined as "yard" (is) "9144/10000 metre" Canadian definitions of imperial units are defined and called "Canandian unit of measurement" So legally, yes you can say you are 5 FT 0 IN tall, but it's actually defined in terms of Meters. — Preceding unsigned comment added by 173.240.190.2 (talk) 15:49, 9 January 2018 (UTC)[reply]

 Done  Stepho  talk  23:00, 10 January 2018 (UTC)[reply]

Anthropic unit category[edit]

I removed this article from the Anthropic units category and Cybercobra reverted it with a comment "please explain." It's basically just a difference of opinion and a question of degree. I think there is strong evidence for the inch having an anthropic basis, but only to the same extent that the meter has been measured by means of an outstretched arm, i.e., occasionally, but not often. However, I've already had this discussion elsewhere, and get the impression that there is community support for a broad definition of anthropic, so I'm not going to challenge the revert. Zyxwv99 (talk) 00:28, 12 March 2012 (UTC)[reply]

You had me puzzled for a minute; it was the see–also, right? It's my opinion that that article needs radical attention. I've made various attempts in the past, but was always blocked by User:Montanabw. But a concerted effort by several editors might achieve something. The main problem is that "anthropic units" just doesn't have the meaning attributed to it there. I believe the best first step would be to add the meanings that are actually attributed to the phrase, and then try to decide if they merit an article. Justlettersandnumbers (talk) 00:53, 12 March 2012 (UTC)[reply]
Sorry, I meant see-also. If it were up to me, the Anthropic units article would be rolled into Customary units, which has already been rolled into Systems of measurement. There it would be subject to more rigorous scrutiny, causing most of it to evaporate. Similarly, the Anthropic units category should be rolled into the Customary units category. As it stands now, it feels as if the Scientology people have taken over, categorizing the metric system as "clear," Imperial units as "preclear," and Greco-Roman units as "reactive mind units." Zyxwv99 (talk) 01:43, 12 March 2012 (UTC)[reply]
OK, I'll support that. Do you want to propose the merge, or shall I? No, wait, there's a problem: Customary units is a redirect to United States customary units. Why is that? Where is our article on customary units? And yes, there is a worrying aura of magical numerology hanging over some parts of this project. Justlettersandnumbers (talk) 10:22, 12 March 2012 (UTC)[reply]
It's Customary measurement systems and it redirects to Systems of measurement. I don't think this is the right time to propose the merger. For one thing, it's already been tried. I think at this point we should just keep working on improving articles on individual units and systems. The better the articles are, the more serious participants the measurement project will attract. At the same time, it would be helpful to start defining the problems and proposing solutions, without necessarily expecting immediate results. My concern is that if we take this on now, we'll just have a dispute that we will lose because we're outnumbered. Can you suggest a forum for discussing this further? Does the WikiProject Measurement have fora where there kinds of issues are discussed? Zyxwv99 (talk) 14:18, 12 March 2012 (UTC)[reply]

Standardisation[edit]

Pulled a few bits together. It would be nice to know when the Canadians set their inch to 25.4mm. Snori (talk) 17:39, 29 August 2012 (UTC)[reply]

The answer is further down in the article, along with a reference. I put it there a few months ago. Zyxwv99 (talk) 17:48, 29 August 2012 (UTC)[reply]

List of minor issues[edit]

  • Lede

Traditional standards for the exact length of an inch varied, but it is now defined to be exactly 25.4 mm.

The length of an inch had nothing to do with tradition. Since ancient times, standards of linear measurement have been regulated as they are today, by standards committees. Sometimes a committee's recommendations are enshrined in law or executive orders, but it is still committees of experts that figure these things out.

There has been more than one inch. They did not all become 2.54 centimeters. For example, the Roman inch, various French and German inches, etc.

  • History section

After 1066...

Nothing happened to British metrology in 1066 other than the Normans making the preservation of existing English weights and measures one of their top priorities.

None of the Welsh definitions of the inch predate the English. This information is based on 14th century manuscripts purporting to be faithful copies of earlier documents but shown by scholars to have been heavily ammended with back-dated material.

Charles Butler, a mathematics teacher at Cheam School...

This whole paragraph is a mess. Apparently this business of going on about barelycorns was a reponse to an enthusiast for the thumb theory, whose unreferenced material once dominated this article. Much of the material here is relevant, just needs improving.

  • Modern standardization

The part about 1866 is confusing, as it suggests that something happened to inch in that year, and that the inch was not approximately 2.54 centimeters prior to 1866.

Just to give a little background on this, during the 19th century standards of precision increased by two to three orders of magnitude. As the result, even high-precision standards tended to become obsolete quickly. That was the situation with the 1799-vintage international prototype meter in the 1860s: it was old and not very accurate. The 1866 law legalized the metric system, but also gave the US meter a reliable definition in terms of the yard. By the 1890s the situation had reversed, as the new platinum-iridium international prototype meter was so reliable that both the US and Imperial yards were defined in terms of it. All these issues became moot in the first decade of the 20th century when wavelengths of the red spectral emission of cadmium became the de facto standard for precision linear measurements.

The easiest way to fix this paragraph (the one mentioning 1866) is to just say what happened in both 1866 and 1893. (See Mendenhall Order.)

Zyxwv99 (talk) 14:43, 30 August 2012 (UTC)[reply]

singular or plural?[edit]

A few weeks ago I made a few edits in which I changed the plural forms of inch, yard, and metre to the singular as they involved values less than one. Shortly thereafter these edits were reverted by User:Stepho-wrs with the comment: "(Revert. Plural#Usage of the plural says Wikipedia uses plurals for decimal fractions - regardless of what your regional variation of English does.)"

At first I thought it was an honest mistake on my part, similar to what happens when a new user tries to "correct" British English by changing it American English, or vice versa. However, I also wanted to know what WP:MOS had to say, so I followed the link. To my surprise, it led to an ordinary (and poorly referenced) article that said, "English also tends to use the plural with decimal fractions, even if less than one, as in 0.3 metres, 0.9 children." Not only is this sentence unreferenced, so is the entire paragraph, as well as the entire section "Usage of the plural." From there I followed a link to English plural but found nothing relevant to this topic. Then I went to WP:MOS but found nothing. Then I looked at the discussion boards and found something here but the discussion was inconclusive.

Then I looked on the internet so see what "regional variation of English" I may have been using. Here's what I found: apparently it can go either way. The plural form is used by the Bank of England, The Economist, and the journal Nature. On the other hand, the singular is used by the OED, the Encyclopedia Britannica, the BBC, the Royal Society of London, the New York Times, the US Government Printing Office Style Guide, the National Geographic Society Style Guide, etc. So like I said, it could go either way. However, the International Bureau of Weights and Measures seems to prefer the singular, the National Physical Laboratory insists on it, and NIST uses the singular. Thus, maybe we need a new rule for WP:MOS that the singular be used for decimal fractions in articles about SI, imperial, and US customary units. Zyxwv99 (talk) 13:28, 28 September 2012 (UTC)[reply]

Hmm, looks like I made a mistake. I started with WP:MOS, followed it's link to WP:MOSNUM and somehow arrived at Plural#Usage of the plural. I thought the last was part of the Manual of Style but it is just an ordinary article. My apologies. You're right that there are many variations in the real world (0.3 metres and 12 foot happens to be the style that I am familiar with). Since WP:MOS and WP:MOSNUM are not clear, I will claim WP:ENGVAR, which states that whichever variation is used should be consistent within the article and that the variation used first is the one to be kept (ie first editor wins, no changing without consensus).  Stepho  talk  02:31, 29 September 2012 (UTC)[reply]
For the time being you are correct. However, what I have in mind is a change to WP:MOS for articles relating to SI, imperial and US customary units for the same reason that we already follow SI guidelines in other issues relating to nomenclature. For example, SI abbreviations have no plural form, thus "10 km" is correct, not "10 kms." However, it would take time to build a consensus for such a change, so for now I'm just putting the idea out there. Zyxwv99 (talk) 02:41, 29 September 2012 (UTC)[reply]
I'd be interested to see your internet links (other than this) that claim so many institutions use the singular for decimals between -1 and +1. I'm more familiar with the plural for all numbers other than unity, but perhaps there have been some recent changes in conventions? I always thought there was a difference between the prose usage (where I would normally use plurals) and the SI abbreviations where the plural is never used. Dbfirs 17:22, 29 September 2012 (UTC)[reply]
Since different institutions do plurals differently, I've no problem with Zyxwv99 raising the issue at WP:MOSNUM. They might accept his proposal or they may shoot him down in flames. Bit pointless to discuss it here though, since this article won't make the policy. Either way, good luck.  Stepho  talk  05:15, 30 September 2012 (UTC)[reply]
Actually, the way these things work is that it needs to be discussed here first, specifically on the talk page of the article where the issue came up. (Something about going up the chain of command, as in "Did you try to resolve it there?") Then it needs to be discussed on the talk pages of the articles that would be affected, since the people who edit those articles need to be given a chance to weigh in. Zyxwv99 (talk) 13:57, 30 September 2012 (UTC)[reply]
Thanks for being fair and open-minded about this. My personal view is that the statement in Plural#Usage of the plural reflects majority usage in all regions (as evidenced by widespread support in the previous discussion and in forums elsewhere), but there might be regional differences that I am not aware of. Obviously any SI unit abbreviations will be in the singular for all values, and the same applies if we use a two-letter abbreviation for non-SI units (0.5 in. or 0.5 mi.). Fractions less than one seem to take the singular also, presumably because they always refer back to the whole unit, but "0.5 miles" seems to be much more common, world-wide, than "0.5 mile", though inserting "of a" makes it singular again since we are then referring to the unit mile. These are just my observations on common usage. Dbfirs 07:06, 1 October 2012 (UTC)[reply]

International Bureau of Weights and Measures - Bureau international des poids et mesures (BIPM) The International System of Units (SI), 8th edition (2006) page 115: The mole is the amount of substance of a system which contains as many elementary entities are there are atoms in 0.012 kilogram of carbon 12; its symbol is "mol". page 142: ...the differences between the national Metres and the international Metre lie within 0.01 millimetre and that these differences... page 144 Appendix 1 Resolution 3 ...the zero of the centesimal thermodynamic scale must be defined as the temperature 0.0100 degree below that of the triple point of water. page 170 CIPM, 2005 that this composition be: 0.000 155 76 mole of 2H per mole of 1H...

National Physical Laboratory (United Kingdom) (NPL) SI Conventions The following is a list of the key recommendations when using SI units: Writing unit names and symbols. For unit values more than 1 or less than -1 the plural of the unit is used and a singular unit is used for values between 1 and -1.

National Institute of Standards and Technology NIST Handbook 44-2012, Appendix C - General Table of Units of Measurement, page C-5, Gunter's of Surveyors Chain Units of Measurement 0.66 foot (ft) = 1 link (li) ... Apothecaries Unit of Liquid Volume 60 minims = 0.2256 cubic inch (in3) page C-8, footnote 8 One internation foot = 0.999998 survey foot (exactly) On the international mile = 0.999998 survey miule (exactly) footnote 9 One square survey foot = 1.000004 square internaitonal feet One square suirvey mile = 1.000004 square international miles page C-9, Note: 1 survey foot = 1200/3979 meter (exactly) | 1 international foot = 12 x 0.0254 meter (exactly) | 1 international foot = 0.0254 x 39.37 survey foot (exactly)

Oxford English Dictionary measurable 4.a. ...(Meteorol., of rainfall) not less than 0.05 mm (formerly 0.01 inch). millitre, n. ...(approx. 0.0338 fluid ounce, 0.0610 cubic inch)... millimetre ...equal to 0.03937 inch... Pascal, n. approx. 0.000145 pound per square inch pica, n.2 0.166 inch

Enc Brit online grain weevil (insect) This small brown weevil is about 3 to 4 mm (0.1 inch) long. www.britannica.com/EBchecked/topic/240837/grain-weevil

Proceedings of the Royal Society of London, Volume 65, T.G. Bonney, The parent rock of the diamond in South Africa, page 229, ...which is about 0·03 inch in thickness.

The BBC Roll out the dough onto a clean, floured surface to form a sausage-shape with a diameter of about 2cm/0.5 inch and cut into 2cm/0.5 inch pieces...

The New York Times, Sept. 14, 1873, page 6 Weather for the Week Sept. 7, rain from 8 P.M. too 12 P.M.; amount of water, .24 inch; Sept. 8, rain from 12 P.M. to 4 A.M.; amount of water, .09 inch... New York Times, Apr 23, 1916, pg. XX4 Queries and Answers The mean cross-sectional velocity of the Hudson River at the Battery, due to land-water discharge alone, is 0.08 mile, the mean for the month of April being 0.18 mile, and 0.04 mile for the month of August.

National Geographic Society National Geographic Style Manual > F > Fractions If the amount is less than one, the unit of measurement is singular: .33 inch (not inches) a day.

United States Government Printing Office U.S. Government Printing Office Style Manual, page 271, Chapter 12. Numerals, Measurement and time, 12.9, d. Decimals: [example], 0.25 inch; 1.25 inches

Board of Governors of the Federal Reserve System Industrial Production and Capacity Utilization - G.17 Release Date: June 15, 2012 Capacity utilization for total industry declined 0.2 percentage point to 79.0 percent, a rate 1.3 percentage points below its long-run (1972--2011) average.

Scientific American ...scores were rising by 0.3 point a year—three full points per decade. Sept 2012, p 44, Can we keep getting smarter? by Tim Folger; They have warmed the earth by roughly 0.75 degree Celsius... Jan 2010, p 45, Climate Numerology by David Biello; each weighing an average of 0.3 gram, July, 2009, p 76, The Ivory Trail by Wasser, Clark & Laurie.

Zyxwv99 (talk) 12:58, 2 October 2012 (UTC)[reply]

Thanks for those excellent references. They almost convince me that I have been getting it wrong all my life (though I still think that common usage is on my side). Perhaps my style is just too old-fashioned! I'll try to find some contra references. Dbfirs 16:03, 2 October 2012 (UTC)[reply]
( ... later) I can't really compete with your detailed research, but I offer a few usages from recent books:
"Trees with a diameter at breast height (d.b.h.) of less than 0.5 inches", Western spruce budworm suppression and evaluation project using ... - Page 8, Douglas L. Parker, United States. Forest Pest Management, 1981.
"Volume resistivity is approximately 1.3 x 1011 ohm-cm at 12 mm thickness (5.0 x 104 megohm-inches at 0.5 inches thickness)", The Shell Bitumen industrial handbook - Page 135, Shell Bitumen - 1995.
"Find the approximate error in the volume of a cube when the side measures 10 inches with possible error of 0.5 inches", Calculus: An Intuitive and Physical Approach (Second Edition) - Page 392, Morris Kline - 1998
"The pressure drop through such a bed is generally 0.5 inches wg", Industrial Hygiene Engineering: Recognition, Measurement, ... - Page 210, John T. Talty - 1988.
"Commercial aluminum, 2 by 6 by 0.0625 inches. Aluminum with 1.5 per cent Mn, 2 by 6 by 0.0625 inches. NN Cl... C2 C3 Duralumin, 2 by 6 by 0.0625 inches. Wrought-iron nuts and bolts, 2 by 0.75 Inches.", Bureau of Standards journal of research: Volume 7 - Page 593, United States. National Bureau of Standards - 1932 Official, but perhaps dated?
"2 mm (0.06 inches) 5 mm (0.18 inches)", 2011 Rapid Excavation and Tunneling Conference Proceedings - Page 525, Steve Redmond, Victor Romero - 2011.
"[1 mm ] = 0.0010936 yards = 0.0032809 feet = 0.03937079 inches ... [1 cm ] = 0.3937 inches", Compact German Dictionary: German-English English-German - Page 718, Heinz Messinger, Langenscheidt, Gisela Türck - 2003 ... and a dictionary usage Dbfirs 16:50, 2 October 2012 (UTC)[reply]
Beware that almost everybody uses singular when dealing with abbreviations (eg 0.5 m), which means many of the above examples don;t address the issue. Here in Australia we generally use plurals for decimal fractions (except when used with abbreviations). So, we say 0.5 metres, 0.5 m, 12 in and 12 inch. But as the examples above demonstrate, this is by no means universal and even differs within the same country. As with other regional issues, I'm happy enough to let WP:ENGVAR be the driving policy (ie edit with first usage decides).  Stepho  talk  23:01, 2 October 2012 (UTC)[reply]
I agree that for every example I can site, someone else could probably find 2 counter-examples, so I am not arguing that I am right on common usage. Instead, I wish to argue first that this is not a regional vs. global issue. I don't have the examples here, but on Google Advanced Search one can select by country. Searching on such terms as "0.2 metre" one finds examples from respected institutions in Australia and every other country where English is spoken. (Australian National University, Sydney Morning Herald, etc.) On the other hand, one could also find as many or more counter-examples.
For me, there are two more pressing issues. First, the idea that common usage shouldn't always trump good grammar, as for example the who/whom distinction or subject-verb agreement. Secondly, there are situations were encyclopedias follow official guidelines, regardless of what common usage says. For example, the International Astronomical Union says that Pluto is not a planet, Germany say Neanderthal should be spelled Neandertal and academia, in violation of common sense, starts spelling it the German way. The people in charge of SI say abbreviations of SI units should have no plurals. These are all examples of a higher authority imposing linguistic rules on encyclopedias and getting away with it.
The only problem is that the evidence I have marshaled thus far is insufficient. The NPS reference suggests there is some sort of SI style guide which I have not been able to locate. I also don't have the expertise or clout to get such a change implemented at WP:MOS (the change being to use the singular for articles about SI, and possibly imperial and US customary units). There are Wikipedia editors who might be able to pull it off, but I'm not one of them. Instead, I just wanted to raise the idea in the way of preliminary discussion, then let it sit on a back burner for five or ten years before raising the issue again. In the meanwhile I just didn't want to leave with people having the misconception that this is a regional dialectical issue. Zyxwv99 (talk) 02:46, 3 October 2012 (UTC)[reply]
I agree that this is not a matter of regional differences, since both styles can be found in America, Australia and the UK, but nor is it a matter of grammar since many who would never (or hardly ever) make an error in subject-verb agreement still insist on one form or the other. You might have to wait until the whole world adopts SI units before the singular style becomes standardised (or standardized if you prefer). There are contexts where I might say "minus one apple" (or centimetre), and other contexts where "minus one apples" (or centimetres) would sound more natural (where the stress is on the minus one, and the apples or centimetres are mentioned in passing), and perhaps the same contextual preference is applicable to zero and to decimals between −1 and +1. Dbfirs 15:36, 4 October 2012 (UTC)[reply]

1 inch = 25.3995 mm in the Oxford Student's Dictionary[edit]

The Oxford Student's Dictionaty, Second Edition, Oxford University Press, 1988, ISBN 9780194311649, states that 1 inch is 25.3995 mm on page 747. I suppose that that's an obsolete definition but where does it stem from? Is it worth mentioning in the article? --Лъчезар共产主义万岁 20:02, 27 January 2014 (UTC)[reply]

I tried the US and UK definitions of the inch that preceded the modern definition (1 inch is exactly 25.4 mm). None of the old values came out to 25.3995 mm. It's clearly an error, and I see no merit in trying to figure out the source of the error in an old student dictionary. Jc3s5h (talk) 20:18, 27 January 2014 (UTC)[reply]
I remembered that my teacher told me that one inch is exactly 25.399998 mm. 333-blue 13:11, 28 February 2016 (UTC)[reply]
Don't believe everything that your teacher told you. Ask why, and check the facts. Dbfirs 13:14, 28 February 2016 (UTC)[reply]

Indian[edit]

In India the inch can be measured according to the requirement of the measurer. The Indian standards says the "inch" is divided into eight divisions but this can vary with the different tapes/scale which are in use for the measurement purpose. There can be 8,16,32 divisions of an inch in tapes/scales available in India so there has nothing to be confused about because the standard is of 8 divisions of an inch and for 16 one division of inch is divided into 2 and for 32 one division of an inch is divided into 4 parts. And now the name of this division is not available in hindi but in urdu this division is called "SOOT" therefore the division of an inch is called soot

1 inch = 8 soot for 8 division tape/scale

1 inch = 16 division that means measurement is more accurate(1,1.5,2,2.5,3...and so on until 8)

1 inch = 32 division that means 1 soot is divided into 4 parts for more accurate readings.

The above was added to the article. I found it difficult to understand and it had no references. Thought it would be better here.  Stepho  talk  11:09, 6 April 2014 (UTC)[reply]

Yes, I think it's better here and not in the article. In the UK also (and probably elsewhere), tape measures are marked in inches and eighths, and sometimes sixteenths and thirty-second parts of an inch. There is no special name for these divisions in English, other than eighths, sixteenths etc. If the original editor wishes to add "soots" to the Hindi or Urdu Wikipedias, then that would be in order (with references). Dbfirs 11:48, 6 April 2014 (UTC)[reply]
Agreed. This text was also added to Soot, where it was even more inappropriate; I've reverted its addition to that article as well. Graham87 14:45, 6 April 2014 (UTC)[reply]

Plural[edit]

is completely standard and per WP:NOTADICTIONARY has no business cluttering up our WP:LEADSENTENCE. That's what Wiktionary entries are for. — LlywelynII 07:43, 16 January 2017 (UTC)[reply]

Assuming my edits are reversed,[edit]

given the traffic around this page, kindly restore them. It's simply wrong to say that the inch became 25.4 mm in July 1959. It became 2.54 cm or (if we're only using formal units) 0.0254 m on exactly 1 July 1959 but only in the United States. Other countries using English units adopted the standard at various dates from 1951 into the mid-1960s and we shouldn't be misinforming readers about that point. — LlywelynII 07:47, 16 January 2017 (UTC)[reply]

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Pronunciation?[edit]

From the "Name" section of the article:

"The English word "inch" (Old English: ynce) was an early borrowing from Latin uncia ("one-twelfth; Roman inch; Roman ounce") not present in other Germanic languages.[1] The vowel change from Latin /u/ to English /i/ is known as umlaut."

OK, reasonable enough. But:

"The consonant change from the Latin /k/ to English /ts/ or /s/ is palatalisation."

Say what? There is no "k" in the Latin source given, "uncia". Nor is there any "t", "s", or "ts" in "inch".

Shouldn't that be, "the consonant change from the Latin "c" to English "ch"...", etc.? — Preceding unsigned comment added by 74.95.43.249 (talk) 02:36, 7 February 2018 (UTC)[reply]

Usage[edit]

Tire sizes are one of the great exceptions to metrification

Almost all wheel diameters are in inches. and of course the coresponding tire inner diameters

almost all wheel widths are in inches.

Large tires for trucks and aircraft are still made to inch specifications for width and height (and of course wheel diameter).


As an example, the Airbus A380-800 lists the following tire for the main landing gear

1270✕455R22 50✕20.0R22

clearly, they are inch items with metric equivlents listed also note that the sequence is different from cars & Light trucks, 50 is tire diameter, 20 is the tire width, 22 is the wheel diameter, this calculates to 75% aspect ratio (50-22=28 /2 =14 height of tire /20 =.75.

A-320 and earlier Airbus ONLY list inch dimensions for tires & Wheels Boeing uses only inches in tire and wheel specifications

The (2017-2021) generation of Formula One tyres sizes are 305/670-R13 (front) and 405/670-R13 (rear) Note: these are specified Height(mm)/Width(mm)-R(adial)Wheel Diameter(inches)

Please add any vehicles with metric wheels here: 1) Buatti Veyron - tires and wheels are bespoke, therfore there is no need to have any interchange capbility. 2)


Trivia: automotive spark plugs have been specified, manufactuered, and labeled in mm for at least 100 years even in countries where every other part of the vehicle was inch based.

All information is readily available on Wikipedia — Preceding unsigned comment added by 75.27.41.149 (talk) 20:16, 6 May 2020 (UTC)[reply]

Not quite accurate. Spark plugs have metric threads but may have imperial thread reaches. On my desk I have an NGK plug labelled D6HS: "D" => 12M1.25 with an 18mm hex, 6 => medium temperature, "H" => ½" (12.7mm) reach and S => "super copper core". Martin of Sheffield (talk) 21:27, 6 May 2020 (UTC)[reply]
In Australia, Europe and probably many other countries, automobile rims are are almost always measured in inches for diameter and width. Tyre inner diameters are correspondingly measured in inches. But other tyre measurements are almost always in mm. Hence an 205/50R15 tyre has 15 inches for the inner diameter and 205 mm for the width portion. Since it is not a simple cut-and-dry thing for inches vs metric, I suggest that we just leave it out. A reader interested in tyre measurements will be looking at the tyre article anyway.  Stepho  talk  20:21, 7 May 2020 (UTC)[reply]

Discussion relating to notation of recurring decimals in this article[edit]

For the record, see Wikipedia talk:Manual of Style/Dates and numbers#Overlining a problem. Any discussion should be taken there. Graham87 (talk) 17:09, 12 October 2023 (UTC)[reply]

US survey inches - no direct sources, OR conclusion[edit]

The Inch#US survey inches section currently says This implies that the survey inch was replaced by the international inch. This is of course a breach of WP:OR, which I suppose seemed necessary because no WP:RS on the matter could be found. On examination, that's not surprising; the only sources for this section don't mention a survey inch either, only units of a foot or more. It may seem obvious that if there is (or was) a survey foot there must be a survey inch, but that doesn't mean there's any substance here or any point in having this section. I'm inclined to remove it. NebY (talk) 18:50, 22 October 2023 (UTC)[reply]

Esri's ArcGIS Pro 3.1 supports the survey inch, and defines it as 1.0/39.37 meters. Our article about Esri claims "Esri is the world's leading supplier of GIS software, web GIS and geodatabase management applications." My experience, which includes search and rescue for the Civil Air Patrol, tends to agree with this. Jc3s5h (talk) 19:42, 22 October 2023 (UTC)[reply]