Talk:United States customary units/Archive 1

Township

 * 1 township = 6 sq mi exactly = 36 sections exactly

If a section is 1 sq mi, then a square which is 6 miles wide would be:

6 X 6 = 36 sq mi

--Ed Poor 15:16 Dec 4, 2002 (UTC)

That's right: a township is equal to 36 square miles = 36 sections = a square which is 6 miles long and wide. AxelBoldt 19:52 Dec 4, 2002 (UTC)

Cable lengths
There are many cable lengths, I've noted the US Navy definition as such, I believe that other cable lengths have also been used in the US (at least the 1/10 nm). -- Egil 12:39 Feb 3, 2003 (UTC)

Water freezing temperature
Info on freezing temperature of salt water (NOT 0°F)

Mass and weight
The bits in the article on mass do not really cover the difference between mass and weight: as I undertand it (not being 100% up to speed on English units) there are two ways to handle this neatly in this system, we can use pound to represent mass, in which case the useful unit of weight (or force) is the poundal. Or, you can use pound to represent weight(force) and the slug for mass.

Would need a rewrite...or do we leave as a non technical description and add an article on slugs, poundals, newtons etc elsewhere? --GPoss 12:24, Jul 23, 2004 (UTC)


 * Both the poundal and the slug (mass) are attempts to use (what we now call) US units in a "coherent" system of measurement, where "coherent" means 1 * 1 = 1 in terms of derived units (such as 1 kg * 1 m/s^2 = 1 N). However, they don't need to be coherent, working by instead adding a dimensionless constant into your equations (such as 1 lb * 1 ft/s^2 * (1/32.2) = 1 lbf).  And before SI was declared to be the "one true metric" there was similar confusion, where some textbooks would use kilograms solely as a unit of force and something called a hyl used for mass.


 * However, I've never really seen either poundal or slug (mass) used outside of high school or first semester physics courses, with the intent to make equations like "F = m * a" easier to remember (instead of "F = m * a / g"). But as far as US law is concerned, "lb" is specifically a unit of mass, and US engineering classes and professional work use "lb" for mass and "lbf" for force. David Iwancio 23:05, 22 September 2005 (UTC)


 * In all engineering fields I know, outside thermodynamics, the slug has been the basis of mass for at least a century. Few people, other than those that like mass balance equations, use pounds mass to my knowledge.  At least not in the correct way (commerce).  Personally, outside thermo, I have never even heard the phrase pound mass (or pound in a mass sense) uttered since I left school. PatrickandBrenda 18:29, 14 August 2007 (UTC)


 * Although I've done no research. Its always been my impression the slug is far older unit than the pound mass.  To my knowledge the pound mass really came to accepted after the steam engine was invented, because steam calculations are much easier when done in pounds mass.  Few other fields I know of care for it.  But I would have to research that to be sure. PatrickandBrenda 18:29, 14 August 2007 (UTC)

SQ
A roof repairman handed me an estimate that says "25.4 SQ". What the hell the SQ could be? I looked up all possible dictionaries. Mikkalai 19:59, 29 Oct 2004 (UTC)
 * Maybe "square".
 * I remember being told that US roofers (tilers?) sometimes use "square" to mean 100 square feet (9.29 m²). "25.4 SQ" could also be intended to mean "(25.4 mm)²", which is one square inch---I doubt the 25.4 just appeared there at random. Or, if you are in the UK, he could have abbreviated squid, which is 1000 £ (you didn't tell in what he estimated). Conclusion: ask the guy. Christoph Päper 16:13, 22 Jun 2005 (UTC)

Links, Chains, Sections, and other survey units.
Being used for surveying, in the US they're defined by the survey foot instead of the international foot. Therefore, the decimal millimeter values were inexact (a link, for example, is exactly 792,000/3937 mm). So I added a note to the preceding text and pointed out that the SI values given were approximate.

Surveying is also the only place I've seen furlongs used formally and rods used at all. [NIST] tends to classify them as being defined in terms of the survey foot, but there are one or two inconsistencies in this link, so I haven't touched those.

I'm also holding off on touching "acre" for the moment (where 640 acres = 1 square survey mile) for the same reason, but I did remove the line on "section." As with "township," it denotes shape as well as area, describing a square with sides of length of one mile. Instead, I added a note pointing to the Public Land Survey System. David Iwancio 22:05, 22 September 2005 (UTC)

Converter Link
I've added a link to a converter website I put together - www.ConversionStation.com. It converts units of measurement from U.S. to metric to english, and more. I hope the wiki community sees it as an asset rather than spam.

including barrel
What about including barrel (25 liquid gallons) with the volume measurements? 24.51.79.57 12:07, 8 May 2006 (UTC)
 * Which "barrel" do you mean? There are many... the oil barrel (42 gal), the beer barrel (31 gal), the liquid barrel (31.5 gal), the dry barrel (26.25 gal)... Marcika 21:56, 7 November 2006 (UTC)
 * I included the most important ones. - Marcika 21:56, 7 November 2006 (UTC)

Links
I changed the SI equivalents under Units of length for values related to link. Mathematically, if a link is 33/50 feet and a foot is 12 inches and an inch is 2.54 cm, then a link is exactly 20.1168 cm and then a chain is exactly 20.1168 m. —Ksn 01:16, 19 July 2006 (UTC)


 * Ah, but a US survey foot is 1200/3937 meter exactly, while an international foot is 0.3048 meter exactly. Since the table is listing survey measure, a link is exactly 792/3937 m, or about 0.2011684023 m. So the values in the table were more precise beforeKsn's "correction". --Gerry Ashton 23:23, 26 July 2006 (UTC)

slight correction to basis for measurements
The US department of wieghts and measure has the standards by which all of our standard and metric units are measured. Example is something like for a foot they have the item that they will say is exactly one foot long and can be used as a standard for calibrating all other measuring devices. This is the same for all the other measurements. Turns out that we do not just have the Si standards and then convert, we have standards for each seperatly.


 * See http://physics.nist.gov/Pubs/SP447/contents.html. You will discover that the US has used a meter bar to define all length units from 1893 until 1960, even the US customary length units. All units of mass have been defined in terms of the kilogram no. 20 since 1893. That kilogram is in the custody of NIST. See also Mendenhall Order. It turns out that today, only mass units still depend on physical artifacts, namely, the various standard kilograms in the custody of BIPM and various national standards laboratories. --Gerry Ashton 19:05, 3 November 2006 (UTC)

Naming
It should be noted that in the United States, the following terms are used (rightly or wrongly) to refer to this system of units:


 * U.S. system
 * Customary system
 * British system
 * English system
 * Imperial system
 * Standard system

Few Americans could illustrate the differences between these systems (if there are applicable differences), and even relatively authoritative resources use the terms interchangeably. This should probably be noted somewhere; I'm not exactly sure how you could cite/source this, though.

This expands upon some previous comments made on this talk page about the ambiguous use of these terms.&mdash;Kbolino 00:49, 4 February 2007 (UTC)

Where in the US are these terms used? I lived 35 years in Western Washington and never heard any of these terms used except Standard. Tools are designated Standard or Metric. 140.160.115.196 (talk) 19:07, 8 February 2010 (UTC)


 * States have documents that specify what school students are expected to learn. For example, Vermont has a Framework of Standards. One of the requirements for grades 5-8 (on page 7.3) is "Convert one measurement to another within the same system (customary or metric) and make conversion between the two systems (customary to metric and metric to customary)".

Old Inch
Hang on, this isn't clear: International measure, agreed in 1959, uses the same definition of the units involved as is used in the UK and other Commonwealth countries. Before that date, those other countries still used separate standards. U.S. survey measure uses an older definition of the units (specified by the former National Bureau of Standards in 1893) which the United States used prior to adopting international measure. Previous to this agreement, the US standard was identical to survey measure. So does this mean that prior to 1959, the US inch was 25.40005mm? If so, that seems to be an important historical point, and is obfuscated by the article.--Farry 13:52, 4 February 2007 (UTC)


 * If you look at Mendenhall Order you will see the US yard was defined as 3600/3937 meter from 1893 until 1959, so the inch would be 100/3937 meter, or approximately 25.400051 mm. If you think the article should highlight this, go ahead. --Gerry Ashton 19:40, 4 February 2007 (UTC)

Ease of use of customary units and citations
Some recent edits seem to be on the general theme of the customary units being easier to use than metric units. I have some concerns about the sources used for the recent additions.

One addition is "The US system of units tends to be based on binary, albeit trinary where that is more convenient, as opposed to the SI system's base 10. While the latter is easier for engineers and bureaucrats in converting units, the former's binary system is centered around units found convenient by regular people, and then the division of those units in half, quarter, eighth, sixteenth, et cetera, producing more chances for a given unit to fall close to the size needed by a user. This benefit has produced a reluctance among its users to adopt the SI metric system, until forced to by authoritarian governments." The footnote contains a quote: "each Imperial measurement is separated into two packets of easily graspable, one digit numbers, plus a packet of 15 possible fractions." which is taken from an Austrialian Broadcasting Corp. (ABC) web site.

Neither the quote, nor the web page as a whole, says anything about SI being forced upon users by an authoritarian government. Also, although the added passage and the ABC web site both generally point out ease-of-use advantages for customary units, the added passage does not seem to be a paraphrase of the ABC web site.

An additional problem is that the ABC web site represents the experience and viewpoint of one person who was interviewed for a radio show, so it is not appropriate to present that viewpoint as the position of Wikipedia.

Another addition is this passage: An example of the source of resistance can be found in cooking: Units of fluid measure are traditionally set up in a binary fashion, with a quart containing two pints, a pint containing two cups, and a cup divided in to half cups, quarter cups, et cetera. Therefore a single unit of measure is generally close to what is needed in a recipe, whereas in metric one is forced to deal in hundreds of milliliters, which to a US user seems arbitary and complicated. A quarter cup is 59 milliliters, already seeming more trouble, and then if you are doubling the recipe you need either a half cup, or 118 milliliters. Again, the US system feels simpler and more useful for conventional, not-scientific purposes. This references the web site http://members.aol.com/footrule/usaband.htm. The home page indicates this is a web site of the British Weights and Measures Association. So there are two issues with this source: can we be sure an AOL member web site really is the web site of the BWMA, and how should we phrase the information to indicate it comes from an partisan organization? A further problem is the cited site is mostly about US states that have switched back from metric to customary for state highway construction or building codes, and has nothing to say about cooking measurements. --Gerry Ashton 23:01, 10 March 2007 (UTC)


 * I have rewritten the first passage mentioned above by adding another source, and making the passage more closely follow the information in the sources. I have eliminated the second passage. --Gerry Ashton 21:51, 11 March 2007 (UTC)

Appropriateness of the term
U.S. customary units or its other two spellings occur insufficiently many times under nist.gov to believe it has widespread meaning. In the Web, its occurrence seems largely copied from the Columbia Encyclopedia. --Whir 03:13, 6 Jan 2004 (UTC)

Many US web sites call them "English units". (See this page for a random example). Can any USian tell me if this is a standard usage in the US? -- Heron 08:51, 31 Mar 2004 (UTC)


 * Yes, it's standard. English & Metric are the terms used when the distinction needs to be made. The "English system"'s earliest citation in the Merriam-Webster Collegiate Dictionary is 1927, and it is in the most recent edition. An alternative would be the "foot-pound-second system" dating from 1892. "English system" is more common, though the subject doesn't come up much. -- Nunh-huh 08:57, 31 Mar 2004 (UTC)~


 * Thanks, Nunh-huh. I added a note to this effect.  -- Heron 09:16, 31 Mar 2004 (UTC)


 * Strictly, it's SI units, not 'Metric'. Jdpipe (talk) 01:51, 16 November 2008 (UTC)

I've actually more commonly heard the term standard units used to describe the US units, as in "perhaps we should someday switch from standard units to the metric system." English system is definitely also used though. --Delirium 02:08, May 25, 2004 (UTC)

My question is who "owns" the term "U.S. Customary Units" if anyone. It seems to be an arbitrary distinction to exclude metric units that are used customarily. For example, the liter and milligram are centainly customary units in the U.S. Asprin comes in 84 mg, 325 mg, and 500 mg sizes. There are no equivalent units on the label. Likewise, with pop, water, wine, mouthwash, etc. they are sold and advertised by the liter. I don't know of anyone that thinks or says "I am going to the store to buy a 67.6 oz bottle of pop. My point is that the liter and milligram should be considered U.S. Customary Units based on the word customary. 67.217.42.76 (Larry) 12:23, 12 August 2005


 * In my opinion, that's a bit of a stretch. Those are two examples where specific industries, which have become dominated by a handful of global companies interested in standardized sizes, using metric, but the rest of the products in the store being sold in other units.  Before multinational pharmecutical companies came about in the later half of the Twentieth Century, for example, remedies were produced and consumed locally and measured out in the units listed under "Apothecaries' Weight."  It's a similar case with soft drinks, dominated by a handful of multinationals interested in standardized sizes.


 * Otherwise, people in the US, by custom, will look at a liter and call it a quart. David Iwancio 22:32, 22 September 2005 (UTC)


 * The liter is a U.S. customary unit. Everywhere else, we use litres :-) Jdpipe (talk) 01:49, 16 November 2008 (UTC)

Reduction of anti-U.S. bias
I made some NPOV edits today. Metric proponents, please try to avoid terminology and phrasing that reflects your critical opinions about non-metric systems and the relative slowness of metrication in the US. There are many legitimate reasons for resistance to metrication; it's not just ignorance, and it has a lot to do with market forces and the economic costs of conversion. Also consider your own country's role in matters: since international trade is often set up in order to protect national economies by requiring foreign companies to establish a manufacturing presence in the country to which they're selling, there is in these situations little or no export market for goods produced in the US, and thus little incentive for US manufacturers to convert since they don't need to be competitive in foreign markets. This is, of course, changing over time, and it should be noted that metrication is taking place in various industries at a rate roughly proportional to the globalization of those industries (globalization itself being a contentious topic... would you want the US to be metric based so much, if doing so would mean an even greater flow of US-manufactured goods into your country?)

Conversion to and from metric for international commerce and communication may not be easy to remember, but is straightforward. And on the whole, US customary weights and measures are quite usable and AFAIK contain no critical flaws. The only real problem seems to be overlapping terminology and is more a matter of laziness in using the appropriate qualifiers. For example, if one says "ounce" when "fluid ounce" or "troy ounce" is meant, the ambiguity is annoying, but that's hardly a reason to belittle a nation and imply the users of such a system are all ignorant, stubborn fools. The systems are just different, and should be described as matter-of-factly as possible. -- mjb 11:11, 26 Jun 2004 (UTC)


 * As much as I would love to see the United States switch fully to the metric system, you have a very good point. --70.82.50.67 20:17, 18 June 2006 (UTC)

Somewhat related to this point, anyone who persists in the belief that use of Imperial units is reserved to the US, Liberia, and Myanmar has not recently asked a Canadian their height and weight. You'll invariably get them in feet-and-inches and pounds.206.116.0.170 (talk) 09:51, 18 February 2009 (UTC)


 * My understanding from reading UK newspapers on the internet is they represent weights of people in 'stone,' rather than kilograms. I do not know if this practice extends to the readers of said newspapers, or the UK populace in general.  In any case it is another example of widespread use non-SI units outside of the USA.130.39.188.24 (talk) 23:21, 21 May 2009 (UTC)


 * Its not a clear cut issue as many countries will say 6foot as meaning 183cm.. its just easier to say 6 foot. same with pints, its just the glass type, if asked how big a pint glass is people would say 473ml and not 1 pint (at least here in Australia) . Hypo Mix (talk) 06:59, 30 August 2009 (UTC)


 * That argument is a non-argument as it works the other way around too. I.e. it's easier to say 1 meter than 3.281 feet if your talking about the length of the meter for instance. Which system gives the "easiest to say" number depends entirely on what your measuring and how precise you want to be! The foot, for example, has a length suitable for measuring peoples lengths since you need only one digit to express the result (in 99.99% of all cases). If you want to be more precise, however, you have to use inches too which isn't a power of ten of the feet. That means you need to use two units to describe one quantity, which can be a problem (in calculations for example). In the metric system you'd just have to add another decimal. This problem arises when comparing different quantities. If you'd use the US Customary System to measure the length of a ship and the length of a person and then wanted to compare the results numerically you'd have to do several unit conversions (in which you need to remember or look up a series of conversion factors) before you'd arrive at an answer. 84.217.234.9 (talk) 22:56, 6 October 2009 (UTC)Martin Ståhlberg, Sweden

mixing units
the article says "(about 3 millimeters per mile)" which is an ugly mix of units only a small number of people would understand (excluding maybe US) especially since there are 'miles' of different lenght please change to millimetres per km or inches per US mile or something similar
 * Since this article is about US units, it's pretty clear we're talking about US statute miles. -- Mwalcoff 23:07, 6 July 2006 (UTC)
 * It’s actually a sensible choice, because the section is about the difference between usual customary and survey units, of which the largest common one is the mile (i.e. both miles). One should give this difference in an independent unit and millimetre does this job well. We could have used micrometres per, for example, yards as well, but mm/mi are probably better imaginable for most readers. Christoph Päper 07:29, 7 July 2006 (UTC)


 * I agree that mixing units should be avoided. I would change this to about one-eighth inch per mile (with a parenthetical note that it is about 3 mm, for metric thinkers). Bcharles (talk) 14:23, 23 June 2009 (UTC)

MERGE REQUEST
The English units page should redirect to this page, and content should be merged. This is an international reference, and English units are not used in England, so the term is misleading and confusing in the global context (even if it the US it is well understood). Regardless of the term that is chosen, there is no need to the duplicate pages English unit and United States customary units. They should be merged. Jdpipe (talk) 01:48, 16 November 2008 (UTC)


 * Keep the "English unit" article and emphasize the historical units that are no longer used. Reserve this article for units still in use, or at least still listed in current laws and regulations. Rewrite the introduction to "English unit" because that intro is very unfocused. --Gerry Ashton (talk) 02:09, 16 November 2008 (UTC)


 * OK, I agree. Jdpipe (talk) 02:24, 16 November 2008 (UTC)

"Imperial" pint size
Is it not true that the Imperial pint is 19.2 fluid ounces, not 20? I know I read this years ago. I will attempt to find a source Rapparee71 (talk) 07:48, 6 April 2009 (UTC)


 * An Imperial pint is about 568 cubic cm. A US pint is about 473 cubic cm. Therefore, an Imperial pint is about 19.2 US fluid ounces. Rapparee71 (talk) 08:26, 6 April 2009 (UTC)


 * Imperial pint info is not that relevant to this article; articles like English units and Imperial units are better ones. -Fnlayson (talk) 13:58, 6 April 2009 (UTC)

Area
Why aren't area measures listed? At the least, even if acre is difficult, there are square feet and square miles. It'd also be important to know if it's supposed to be measured in survey feet or not. 63.87.189.17 (talk) 22:15, 13 May 2009 (UTC)


 * I suppose no one thought of it. I believe the main trouble of substituting international feet for survey feet is with coordinate systems where the origin may be hundreds of miles from the project. The change in area of a project when international feet are substituted for survey feet is probably within the measurement error. Also, I don't think there is any nation-wide answer to whether the acre is composed of square internatioal feet or square survey feet; it probably varies from state to state, and some states probably don't have any law or rule. --Jc3s5h (talk) 22:22, 13 May 2009 (UTC)
 * Found the answer in the NIST handbook (external link at bottom of article), and it's pretty clear that it's based on survey feet and miles: Appendix B, Section 2.2.5: "We call this foot the U.S. Survey Foot, while the foot defined in 1959 is called the International Foot. Measurements expressed in U.S. statute miles, survey feet, rods, chains, links, or the squares thereof, and acres should be converted to the corresponding metric values by using pre-1959 conversion factors if more than five significant figure accuracy is required."
 * And, in Appendix C, Table 2: "In these tables where _foot_ or _mile_ is underlined, it is survey foot or U.S. statute mile rather than international foot or mile that is meant."
 * ...snip..."1 acre = 43 560 square _feet_""640 acres = 1 square _mile_"
 * The underscores are supposed to indicate the words underlined in the source.
 * Anyway, this information, and the rest of the area measurements, needs to be put in here. If I have time in the near future, I'll work on it.

63.87.189.17 (talk) 17:56, 15 May 2009 (UTC)

Request for Comment: U.S. survey units other than foot
Doubt exists whether, in the U.S., the units rod, chain, link, statute mile, and acre are based on the international foot or the survey foot. Appendix C, NIST Handbook 44, 2006 edition, indicates they are based on the survey foot. However, a discussion at Talk: Mile disputed the correctness and authority of this source. Input is sought on whether this source is reliable for this group of facts.

User:Jc3s5h has e-mailed the National Institute of Standards and Technology concerning this issue but the e-mail was ignored. --Jc3s5h (talk) 19:42, 15 May 2009 (UTC)


 * Per :
 * 1893–1959: 1 yd (US) = $3600/3937$ m ≈ 0.91440183 m;
 * since July 1, 1959: 1 yd (US) = 1 yd (international) = 0.9144 m;
 * exception: US geodesic survey only continues to use pre-1959 length units as long as necessary.


 * This seems to settle the question. But actually it does not, because the units rod, chain, link, statute mile and acre are normally only used by surveyors. It seems that the exception for "US geodesic survey" was interpreted as a licence to introduce an internal inconsistency into the system. This was clarified officially in 1975. See Appendix 9 of this book. Chapter 12 of the same book explains what this means for the statute mile: "Although the term statute mile (5280 feet) can be interpreted to be either the survey mile or the international mile, in the United States the U.S. statute mile remains the same as the U.S. survey mile."


 * Thus, counterintuitively, Appendix C is correct even in these arcane details. I guess the only reason these absurd inconsistencies haven't pushed the country to metrication yet is that almost nobody measures to the level of precision where this actually matters. --Hans Adler (talk) 23:22, 15 May 2009 (UTC)

[edit conflict]
 * I've no desire to enter into the discussion of U.S. constitutional law at Talk:Mile. However, unless there are more recent texts of which I'm unaware, the U.S. situation is clear. It is expounded in 33&nbsp.FR 10755 (July 27, 1968) and 40 FR 3486 (January 22, 1975).
 * The relationship "1 statute mile = 1.609 kilometers" (33&nbsp.FR 10755) was not listed as exact by the (then) National Bureau of Standards.
 * The U.S. survey foot continues to be used for "mapping and land measurement" (40 FR 3486): as the five units mentioned above are only ever used in the context of surveying, it is logical that they be based on the survey foot. If they were ever to be used in "normal commerce throughout the United States", they would be based on the international foot for the purposes of commerce. They won't be, of course, which illustrates why the argument is more political then practical.
 * I should mention that the U.S. survey foot is precisely defined as $1200/3937$ meters, and has been since 1893. As 40 FR 3486 states, "Metric equivalents to more figures [than those quoted in 33&nbsp.FR 10755] can be obtained from the survey foot. […] Metric equivalents of all surveyor's units, e.g. rods, links, and chains, are derived from the survey foot." The difference between the two measures is just over one thou, and almost exactly 3 mm, per mile. Physchim62 (talk) 23:48, 15 May 2009 (UTC)


 * The statute mile is certainly used in commerce, although probably never to a degree of precision where the difference between the survey mile and international mile would matter. One such example is the fee for taxicabs. --Jc3s5h (talk) 01:35, 16 May 2009 (UTC)
 * But doesn't trading land also count as commerce? To make matters worse, since National Geodetic Survey has completely switched to metric internally, an important source of national uniformity for the surveying units is now missing. As a result at least one state is publishing data in international units (or has done it at some time in the past), creating an additional source of uncertainty. See response to "What are the 'official conversions that are used by NGS to convert 1) meters to inches, and 2) meters to feet?" in the NGS FAQ. It also mentions a contact in NGS for further questions.
 * I guess the best thing we can do is list approximate conversion and the two exact conversions (i.e. one as a fraction) for all units of length and all derived units, explain the legal situation, and explain whatever we find out about actual usage. --Hans Adler (talk) 07:39, 16 May 2009 (UTC)
 * PS: Here is a book with information very similar to that in the NGS FAQ. --Hans Adler (talk) 07:43, 16 May 2009 (UTC)
 * No, trading land doesn't normally count as "commerce", because it has its own special rules, but that's beside the point. Most modern day-to-day land surveying is done with laser theodolites, which work with unstabilized He-Ne lasers and so have a relative uncertainty of 1.5 (see Recommendation 2 here). The 2 ppm difference between the survey foot and the international foot is of no relevence for the area of a gien plot of land.
 * However, the difference becomes important in the position of that plot of land. In traditional surveying, position is related to distance by repeated triangulation from a given reference point: hence, any error in the conversion factor is cumulative. To convert a survey system from feet to meters requires a redetermination of all the fixed points in meters. As the NGS FAQ points out, this has now been done and the North American Datum of 1983 is in meters: this was 27 years after the adoption of the international foor (the "1983" Datum wasn't completed until 1986). However, seven states use State Plane Coordinates which have been reconverted from meters to survey feet…
 * Incidentally, the U.S. is not the only country to retain a survey foot. There is an Indian survey foot, defined as 0.3047996 m, which survived metrication (see Schedule to the Standards of Weights and Measures Act 1976) and is even closer to the international foot than is the U.S. survey foot! Physchim62 (talk) 13:03, 16 May 2009 (UTC)
 * The relation of the survey foot to position rather than length in a strict sense explains why there is no "UK survey foot" — the retriangulation of Great Britain (1936–62) was done in metres! Physchim62 (talk) 13:24, 16 May 2009 (UTC)


 * The United States Survey of the Coast in the early 19th century, and all successor agencies, including the modern National Geodetic Survey have used the meter internally, but in some cases have published their results in survey feet. My impression is that surveyors in private practice usually use some variety of feet. --Jc3s5h (talk) 14:45, 17 May 2009 (UTC)

This discussion seems to be over, and the conclusion seems to be that if a precise definition is required, write to your congressman or senator and ask him/her to pass a law to settle the matter. Any further discussion? --Jc3s5h (talk) 14:45, 17 May 2009 (UTC)
 * I think the point that comes out is that you need to check with your State congressman or State senator, as they are the ones with the power to make a practical decision. The federal government doesn't seem to care that much, as it only uses meters for the measurements where the difference would be important. Physchim62 (talk) 16:30, 18 May 2009 (UTC)
 * In particular, you seem to assume that all U.S. statute miles must be based on the survey foot, which is contradicted by several U.S. references. I stand by my position at mile that the statute mile is 1760 yards, whatever your definition of the yard! Physchim62 (talk) 16:34, 18 May 2009 (UTC)


 * Since the constitution gives the Congress the power to establish standards of measure, state legislatures probably have no power to overrule the Congress. But as anyone who follows the marijuana debates can tell you, lack of power will not stop them, and they often succeed in doing what they have no power to do. (The same is often true with the Feds usurping state power as well.) --Jc3s5h (talk) 17:35, 18 May 2009 (UTC)
 * Under the normal interpretation of Police Power, the states cannot overrule the U.S. Congress in areas which the Constitution reserves to the federal government (such as weights and measures), but they can pass complementary laws: after all, it is the states which do the practical work of inspecting commercial weights and measures. In practice, given the small number of federal statutes on the subject, it means that no state can outlaw the metric system, or redefine the metric system in its own terms.
 * It is also the states that passed reception statutes, which would define the U.S. customary system in terms of English law in the 1770s (ie, before the codification of the Imperial system in 1824). That's why I'm confident with my definition of the mile in terms of the yard (either yard if you wish) rather than the foot, even though the latter might seem more natural to modern Americans.
 * As for the survey foot, it seems that the federal government didn't want a fight with the states over an issue of no practical importance. The 1959 statement was specific that the survey foot would continue to be used "until such a time as it becomes desirable and expedient to readjust the basic geodetic survey networks in the United States, after which the ratio of a yard, equal to 0.9144 meter shall apply." The basic geodetic survey networks were readjusted in 1983… Physchim62 (talk) 10:43, 21 May 2009 (UTC)

Nautical Mile
The Nautical Mile is common among US sailors and aircrews. Is there a way to work this in here? 130.39.188.24 (talk) 23:33, 21 May 2009 (UTC)
 * I'm working on it, but I'm looking for reliable definitions of the U.S. cable and the U.S. fathom to go with it. The U.S. has used the international nautical mile since 1954 (4.1 feet shorter than the traditional U.S. nautical mile). Physchim62 (talk) 08:53, 22 May 2009 (UTC)

cooking measures
I have moved the section on cooking measures up and made it a subsection of the section on volume. I am also adding accurate SI equivalents with significant figures consistent with the rest of the article.

I propose merging the table here with the table on liquid volume units, as it overlaps with it, and units are designated as parts or multiples of units in that table. The designation of these units as "cooking measures" is arbitrary. They are used for a variety of purposes as are most units listed in the article. A link to the cooking measures article under "see also" seems more appropriate than a separate section. Bcharles (talk) 14:17, 23 June 2009 (UTC)


 * It's just a short table and it lists US cust. cooking units. Not a problem now, imo. -Fnlayson (talk) 15:34, 23 June 2009 (UTC)


 * My concern is not so much the extra table for cooking measures, but that these measures are not included on the general table for units of volume. Teaspoon, tablespoon and cup are used for much more than just cooking.  Moreover, they are part of a standardized system of measures based on halves, quarters and thirds (in the case of the teaspoon) that is continuous from minims and drams to barrels and hogsheads.  Separating these out leaves awkward and potentially confusing gaps.


 * The stick of butter is the only unit that is not general. It is not standardized and is specific to butter and margarine. I think it should be left to the separate article on cooking measures.  Other cooking measures not here include the pint, quart, pound, ounce, etc. Bcharles (talk) 18:51, 23 June 2009 (UTC)


 * Fair points. So those will be moved to the current liquid volume table or something else? -Fnlayson (talk) 19:28, 23 June 2009 (UTC)


 * I would like to move the tsp, Tbsp and cp to the liquid volume table and to drop the "stick" (or mention it in a paragraph on common cooking measures). Bcharles (talk) 19:42, 23 June 2009 (UTC)

ml or mL
I know it says "mL" on US soft-drink bottles, but isn't ml the more correct, internationally accepted term? The article mixes these two different ways of "spelling".


 * From BIPM:


 * This unit and the symbol l were adopted by the CIPM in 1879 (PV, 1879, 41). The alternative symbol, L, was adopted by the 16th CGPM (1979, Resolution 6) in order to avoid the risk of confusion between the letter l and the number 1. The present definition of the litre is given in Resolution 6 of the 12th CGPM (1964).


 * As I recall, they also recently reaffirmed that it isn't proper to use a script/italic l as a symbol.


 * Since both lower-case and capital are equally correct as far as BIPM is concerned, the difference is semantics. The US (and possibly Canada, don't know) tends to use the capital L, Europe seems to prefer the lower-case l or the disallowed script l.  Guppy313 23:34, 29 October 2005 (UTC)

The symbol used to be a lower case L but the USA objected (rightly, in my opinion) that it was too easily confused with the digit 'one'. The use of the upper case L was legitimised by the BIPM and both symbols are now acceptable. Here in UK I see mostly lower case L when preceded by prefixes (e.g ml) and upper case when on its own (e.g. 2 L bottles of carbonated drinks). I wish we would just switch to the upper case L and use it consistently. Blaise 22:38, 28 March 2007 (UTC)


 * IMO this came from usuall style of handwriting in english-speaking countries. English-speaking people usually write "1" only as one vertical line, instead of full "1" and they write with lowercase letters instead of cursive writing. "12l" written like this iss indeed exactly same as "121". —Preceding unsigned comment added by 88.101.76.122 (talk) 13:09, 21 January 2008 (UTC)


 * Both l and L are correct, but that doesn't mean we cannot have a view on which is preferred for WP articles. I agree with Blaise that L is less ambiguous. Thunderbird2 (talk) 17:05, 21 January 2008 (UTC)


 * Actually, I thought that it was capital L because it was a derived unit. The only base SI units with capital letters are named after people, and every derived unit I can think of is a capital letter or a greek letter.  In America, everyone uses capital L, even in mL.  That is, everyone who doesn't Instant Message or text 24/7. Exp HP (talk) 01:20, 6 October 2008 (UTC)

The problem could be avoided entirely by using the equivalent cubic length unit of dm3 derived from the standard volume unit m3  :) - Parsa (talk) 16:59, 24 August 2010 (UTC)

I agree with the last poster - I thought the SI units are m, s, kg, A (plus something for light), litres being a derived unit. So should that section not just use m^3? —Preceding unsigned comment added by 128.232.133.79 (talk) 20:08, 10 May 2011 (UTC)

Questionable Opening paragraph
"The U.S. is the only industrialized nation that does not mainly use the metric system in its commercial and standards activities"

Thats a very loose statement, as it also applies to the UK‎ because usage of Imperial unit is widespread; body height (measured in feet, inches).. body weight (measured in pounds, stone).. road sign distance (measured in yards, miles).. car speed (mph)... beer/milk (measured in pints).. petrol (gallon).. etc etc. Its a misnomer that the UK‎ has "officially adopted the metric system" because Imperial is used throughout (for example its illegal to have road signs in metric). The only thing the UK has agreed to (to appease Europe) is to allow metric appear ALONGSIDE imperial measurements in SOME cases... but everyone uses imperial anyway. StiffyAdams 19:52 Feb 15, 2010 (UTC)


 * The part about the UK using customary units for petrol and road signs seems to be true, from what I've read, but that's only one small part of "commercial and standards activities". In the market, milk is only a small part of what is offered for sale. In a pub, the beer is sold by the pint; I imagine few of the other items for sale in a pub are measured out to the customer (I'm pretty sure I'd never hear a server in a pub say "here's your 400 g of bangers and mash"). The pub itself most likely buys all its supplies in metric units. And personal measurements are not commercial when used in casual conversation; they would only be commercial if health professionals use feet, inches, stones, and pounds, because the health professionals are getting paid. So are feet, inches, stones, and pounds, used in professional health care settings?


 * I think the weakest part of the phrase is "standards activities" because a great deal (maybe a majority) of US standards activity is conducted in metric. Jc3s5h (talk) 22:32, 15 February 2010 (UTC)


 * When I lived in the UK, from 2002-2006, a law had been passed that all goods and items sold would have the metric measure labelled as the PRIMARY unit. However, they still listed the old imperial units in smaller print. You would find such oddities as 2.1 Litres of milk (instead of just 2) as they original bottle size was in pints or whatever. It is therefore not a misnomer, but an official UK law to use the metric system first and foremost. However, there is a lengthy conversion process to go through for cars, street signs etc. Fortunately in Australia we've been using the metric system much longer, and it's only the old people who still use a few antiquated measures, mainly for body heights and weights. —Preceding unsigned comment added by 202.89.162.154 (talk • contribs) 13:05, 6 November 2010


 * The only things I'm aware of that officially use imperial in the UK are road signs (miles and mph) and beer (in pints). Everything else officially uses metric (though the milk is sold in 578ml bottles which happens to be the same a pint), and though beer is in pints, wine and spirits are sold in ml. Petrol certainly hasn't been sold in gallons for 20 years or more, and though many people describe themselves as 6" the docotor would record 1.8m (such as to calculate BMI, which is metrically defined). —Preceding unsigned comment added by 128.232.133.79 (talk) 20:21, 10 May 2011 (UTC)

Calories
Why are calories listed here? These are metric. J IM ptalk·cont 22:08, 16 February 2011 (UTC)


 * According to this federal register notice the official interpretation of SI for the U.S. may be found in NIST special publications 330 and 811. In S.P. 811, section 5 table 11 indicates the calorie is outside the SI and not acceptable for use with it. Since SI is the only form of the metric system officially recognized in the US, then what can we call the calorie? It is traditionally used in the U.S. and falls in the same category as the foot, inch, BTU, etc., in that the government is aware of it but the Congress has never enacted, there is no current federal legislation recognizing any measurement system other than SI. Jc3s5h (talk) 22:25, 16 February 2011 (UTC)


 * The calorie is the amount of energy required to heat one (kilo)gram of water up by one degree Celcius. It's metric.  There's nothing US customary about it.  If the US government doesn't recognise non-SI metric units as actually metric, that doesn't make them customary ... it just makes the US government mistaken. They could write a law defining a carrot as a fruit, that wouldn't mean that it is a fruit. J IM ptalk·cont 01:18, 17 February 2011 (UTC)


 * You're right, but the 2 calories lines are in the "Other units" section. -Fnlayson (talk) 02:47, 17 February 2011 (UTC)


 * There is not now, and never has been, any systematic federal definition of American customary units. American customary units are whatever units Americans customarily use. The calorie has been around about as long as other heat and energy units, and indeed, a large fraction of the period of independence of the U.S. So who is to say it can't be metric and customary at the same time? No one can say that officially the calorie isn't a customary unit because there is no official definition of a customary unit. Since NIST is the main force behind any measurement laws, and NIST is anti-customary, it is unlikely that Congress will ever pass an official definition of customary units. NIST just wants to ignore them and hope they eventually go away. Jc3s5h (talk) 03:01, 17 February 2011 (UTC)

US is the only industrialized nation...
"The US is the only industrialized nation that does not mainly use the metric system in its commercial and standards activities"

99.238.33.85 (talk) 21:27, 19 May 2009 (UTC)
 * Well, on a de facto level, Canada also doesn't mainly use the metric system in its commercial and standards activities, its about 50/50.

I disagree with the above, any Cdn under 40 lives predominantly in metric. Gas is sold in litres, speed limits are metric, milk is in litres, we know and report temperature in celsius, it's really only human heights and weight in imperial (informally, not officially) and fruits and veg in supermarkets (though the usually get rung up in metric, but advertised in imperial) — Preceding unsigned comment added by 198.90.95.165 (talk) 16:42, 27 August 2015 (UTC)


 * Actually that's wrong. Officially speaking both the USA and Canada use SI to define everything. Canada has brought the use of SI right to the consumer in almost every case. There are still exceptions such as lumber dimensions-though it's worth pointing out that the official sizes of the lumber and the calibrations of the machines are in SI. Masses of goods are measured in grams and kilograms. Volumes of liquids in litres or millilitres. Distances are metres and kilometres (and speeds in km/hr). Temperatures are in °C. Any official weigh scale or measuring device is properly calibrated in SI units and configured to display those. So Canada does far more than half its commercial activity in SI.  — Preceding unsigned comment added by 142.104.247.101 (talk) 16:05, 23 August 2013 (UTC)


 * It would be a really hard issue to put a number on. For example, would you go by number of units sold or by cost? If shoppers seem to pay attention to the customary number on the label, but it would be illegal to market the item without an SI quantity on the label, does that count as customary or SI? Lots of tricky questions. --Jc3s5h (talk) 22:06, 19 May 2009 (UTC)


 * Well, when you say "3 inches" you are actually saying "3 x 25.4 mm" since "inch" is defined in terms of mm. The "inch" does not exist as an independent/organic unit of measurement, but merely as a multiple of the metre. I guess you could label products with a little bit of mathematics: what's to stop a label saying "LENGTH: 101.6 mm = 4 x 25.4 mm"? That is totally SI compliant, and the fact that 1 inch = 25.4 mm is something everyone using inches should know anyway (education system notwithstanding). 118.90.25.232 (talk) 10:58, 21 February 2010 (UTC)


 * I could think of something to stop a label saying "LENGTH: 101.6 mm = 4 x 25.4 mm". J IM ptalk·cont 01:21, 17 February 2011 (UTC)


 * Why is the US the only developed country to stand out against the international metric system? It always seemed odd to me that American's should hold so steadfastly to a pre-1824 British system of weights and measures. Talk about being backward...  — Preceding unsigned comment added by 124.197.15.138 (talk) 20:14, 27 August 2011 (UTC)


 * Maybe for the same reason that some people still grow their own vegetables, shop organic, and prefer heirloom varieties to the corporate agribusiness foods that the big supermarket chains sell. Or for the same reason that the Chinese, Japanese, Koreans, Russians, Arabs, Hindus, and Israelis still aren't using the "modern" alphabet. Zyxwv99 (talk) 18:32, 26 November 2011 (UTC)


 * You're an ass.Jersey John (talk) 09:06, 29 November 2011 (UTC)

Hmm... I think this sentence is somewhat misleading. According to the source:
 * "At this time, only three countries - Burma, Liberia, and the US - have not adopted the International System of Units (SI, or metric system) as their official system of weights and measures. Although use of the metric system has been sanctioned by law in the US since 1866, it has been slow in displacing the American adaptation of the British Imperial System known as the US Customary System. The US is the only industrialized nation that does not mainly use the metric system in its commercial and standards activities, but there is increasing acceptance in science, medicine, government, and many sectors of industry."

Even in this discussion, at least one person has made the mistake of thinking the US is the only country not to adopt SI units. I think the first fact is more solid; "mainly" as a description is both ambiguous and subject to change. --Carbon Rodney 06:57, 28 August 2012 (UTC)


 * There's been some discussion of Burma and Liberia on other weights-and-measures related articles. Apparently Liberia has already gone metric, while Burma's target date is some time in 2012. I think Burma has met it's goal already, except for land measurement, which is still in imperial units. The most commonly cited source for this kind of information is the Weights and Measures appendix to the CIA World Factbook. However, the print edition is one year behind the online edition, which is one year behind the classified edition. Also, no guarantee that Appendix G is up-to-date in any edition. Zyxwv99 (talk) 13:04, 28 August 2012 (UTC)


 * Thanks for the info. The edition info on the web page is not clear; it states the Factbook is updated every week.  That's more like editorial changes though. -Fnlayson (talk) 17:26, 28 August 2012 (UTC)

Often?
"... and U.S. medical practitioners often use degrees Fahrenheit for body temperature."

I think you'd be hard pressed to find a hospital, clinic, or doctors office in the US that doesn't use F. Saying often seems to underplay the near ubiquity of F in medical use. Maybe change often to generally or usually or almost always? 76.226.202.228 (talk) —Preceding undated comment added 06:38, 11 February 2010 (UTC).


 * My recollection in the last few years is some US medical treatment locations use Celsius, some use Fahrenheit. I think a source is needed that conducted some kind of survey in order to know the best word to use. Jc3s5h (talk) 16:00, 11 February 2010 (UTC)


 * As of late, the more elite hospitals are switching to full metric usage. Something to do with minimizing conversion errors, misdosing of drugs, especially for children.  Medical institutions that tend to cater to the lower classes will continue to dumb down units. 68.105.199.216 (talk) 16:50, 13 October 2012 (UTC)

Mass
Is the pound considered to be a unit of force or mass in the U.S. ? Here in the UK the lb is obsolete, but it was legally defined as a unit of mass, equivalent to a stated fraction of a kg in the Weights & Measures Act (1963), and there is never any ambiguity about it. But judging from what I have seen on the internet this is a matter of controversy and confusion in the USA. Do you have anything equivalent to an Act of Parliament over there which gives an authoritative answer to this question ? A related point is that historically in England, up until 1963, the pound Avoirdupois was considered to be a force or weight. So the historical aspects of the main article are incorrect in discussing the historic English unit under the heading of mass. Anyone who is interested in the history of this unit would be sensitive to this matter, so I think it should be corrected. In anticipation of any dispute over this, I will refer to the Weights and Measures Acts of 1878 and 1958 and 1963, and also, as a matter of technical interest, to 'Useful Rules and Tables' by W J M Rankine, (Professor of Engineering at Glasgow University, and originator of the Rankine Cycle) London, 1889. Rankine defines weight as a gravitational force (p 305), and the lb as the weight of a certain piece of platinum under stated conditions of temperature, atmospheric pressure, and location (all pertinent to the weight of a certain mass) on p 97. On p 245, Rankine defines absolute units of force (as distinct from units of weight) thus - ‘Absolute units of force in the weight of an unit of mass: in British units 32.2 nearly…’ (p 245). This can be interpreted as meaning that the absolute unit of force in the British system is 1/32 lb-wt. Furthermore, in giving a rule for calculating centrifugal force (p 246), Rankine states - 'Multiply the weight of the mass by the square of its linear velocity and divide by the radius. The result will be in absolute units which may be converted into units of weight by dividing by g'. This rule only makes sense if 'the weight of the mass' is measured in pounds. Thus if we take a certain mass having a weight (gravitational force) of 1 lb-wt, rotating with a speed of 1ft/sec at one foot radius, the centrifugal force will be 1 absolute unit or 1/32 lb-wt, which is correct. The 'absolute force unit' of ~1/32 lb-wt was called the poundal in the foot-pound-second system, and was defined as the force required to accelerate a mass of 1lb at 1ft/sec^2. In the UK the pound changed from being a force unit to being one of mass in 1963; compare the Weights and Measures Acts of 1958 and 1963; the former defines the pound by reference to the W & M Act of 1878 in which the pound is a weight, while the latter explicitly states that the pound is a mass. Dr A. J. Smith CEng Sept 2010 —Preceding unsigned comment added by 82.32.49.157 (talk) 13:39, 20 September 2010 (UTC)


 * For purposes of trade and commerce, the pound is a mass in the US; see Refinement of values for the yard and the pound. However, it is used as a unit of force as well, and which is intended must be determined by context. Jc3s5h (talk) 14:45, 20 September 2010 (UTC)


 * ''MONDAY, December 17th, 1792.
 * Agreeably to the order of the day, the Senate resumed the consideration of the report of the committee made April the 5th, 1792, on the subject of weights and measures, together with the motion made thereon the 6th instant—Whereupon,
 * A motion was made to postpone the consideration thereof, and to
 * Resolve, That the present measures of length be retained and fixed by an invariable standard; that the measures of surface remain as they are, and be invariable also as the measures of length to which they are to refer; that the unit of capacity now so equivocal, be settled at a medium and convenient term, and defined by the same invariable measures of length, that the more known terms in the two kinds of weights be retained, and reduced to one series, and that they be referred to a definite mass of some substance, the specific gravity of which never changes; and that a committee be appointed to bring in a bill accordingly—and after debate,
 * Ordered, That the consideration of this motion be deferred until tomorrow.
 * 6th. That the unit of weights shall be a pound, which shall be equal to the pound Avoirdupois, now in use, and shall be equal in weight to a quantity of rain water, twenty cents of a foot square, and forty cents deep, or sixteen thousand cubic cents of a foot, measured and weighed in a cellar of uniform natural temperature.''
 * -- Journal of the Senate of the United States of America: being the second session of the Second Congress, begun and held at the city of Philadelphia, November 5th, 1792, and in the seventeenth year of the sovereignty of the said United States.
 * Printed by John Fenno, 1792 - 100 pages

Zyxwv99 (talk) 02:30, 18 November 2011 (UTC)

Troy weights
This is not correct:
 * "To alleviate confusion, it is typical when publishing non-avoirdupois weights to mention the name of the system along with the unit. Precious metals, for example, are often weighed in "troy ounces", because just "ounce" would be more likely to be assumed to mean an ounce avoirdupois."

Look at the troy ounce article. There's a picture of a gold bar that has the word "ONE OUNCE FINE GOLD" stamped on it. Go to Google Images and try finding a picture of a bar of gold that has the word "troy" on it. Lots of bars denominated in ounces, but they don't say troy. In the precious metals trade, when you say "ounce" people just assume you mean troy. In academic, encyclopedic writing, you would of course be more specific, but I mean "in the trade" which is essentially common usage.Zyxwv99 (talk) 01:57, 18 November 2011 (UTC)


 * The case of ounce being stamped into gold bullion (or any other precious metal) is an excellent example of the context clearly meaning the weight is not avoirdupois. But having "ounce" written generally, or associated with most household or industrial goods would almost certainly imply avoirdupois.  —EncMstr (talk) 03:59, 18 November 2011 (UTC)

External links modified
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Precision for dry measures
@User:64.132.59.226: You must start with values given in a reliable source, in this case, Handbook 44 which is the law in most states of the United States. Your edits made conversions base on the conversion factor (0.254 dm/in)^3, which is exactly true, but that's not enough. The value before conversion must be given in a reliable source.

Also, sources mentioned in an edit summary don't count, because the reader is not aware of them. Reliable sources must be included in the citations given in the article. Jc3s5h (talk) 17:33, 4 October 2017 (UTC)


 * @User:Jc3s5h: I copied the value exactly from the Reference 14 chart on the top of page C-11, which is the 487th page of the PDF. Why did you undo the correct value 33.600  312  5 and indicate that you were making it better reflect the source?  64.132.59.226 (talk) 18:12, 4 October 2017 (UTC)


 * I did not notice that exact values were available in the source, because you did not update the footnote to indicate the page number that contains the exact values. Jc3s5h (talk) 20:03, 4 October 2017 (UTC)

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History section NOT about the history of the USCU?
so the history part of the article is about the metric system and not about the USCU at all! what's up with this? Robow87 (talk) 13:46, 4 February 2013 (UTC) — Preceding unsigned comment added by Robow87 (talk • contribs) 13:43, 4 February 2013 (UTC)


 * The History section is merely misnamed. It explains the anomaly that the US is still not properly metricated, and in fact is the most backwards country in the world in that respect.
 * There isn't much obvious information (of the kind that always gets added to Wikipedia articles) about the history of the US customary units in general. There is a lot to say about individual units, and that historical information belongs with the detailed discussion of those units. Hans Adler 14:52, 4 February 2013 (UTC)


 * No reason for such negative and biased comments about the system and the US. This is not a discussion forum.  Maybe you should take that to another site... -Fnlayson (talk) 17:55, 4 February 2013 (UTC)


 * Sorry if you don't like reality's 'liberal' bias, which may have been a bit too obvious from my summary of the section that is now titled "Background". My post was on what to do with this article. Do you have something to contribute to that topic? Hans Adler 19:55, 4 February 2013 (UTC)
 * A nice scholarly annotated neutral discussion about how a country with a proprietary and obsolete system of weights and measures was able to take on the metric world in battle and win, would be quite informative. --Wtshymanski (talk) 20:18, 5 February 2013 (UTC)

Jack
Should the Jack (https://en.wikipedia.org/wiki/English_units#Volume) (half a gill) be included in the list of volumes? Also, it may be helpful to include a table that shows the units related by a factor of 2. Jimktrains (talk) 20:39, 1 August 2013 (UTC)

Dispute over "agreed to"
The article contains the following sentence:
 * This definition was agreed with the United Kingdom and other Commonwealth countries, and so is often termed international measure.

It should read,
 * This definition was agreed to with the United Kingdom and other Commonwealth countries, and so is often termed international measure.

I corrected it, and reverted my correction. The sentence is incorrect because agree is not a transitive verb. The parties did not "agree the definition": they agreed to it. The sentence would mean the same if it were written without the passive construction:
 * The United States agreed to this definition with the United Kingdom and other Commonwealth countries, so the definition is often termed international measure.

but the passive construction is appropriate, since the definition, not the United States, is the focus of the sentence. The sentence should stand as I corrected it.

J. D. Crutchfield &#124; Talk 20:22, 25 March 2015 (UTC)


 * Why not just rewrite the sentence to avoid the disputed usage, if it's possible to do so clearly and succinctly? - BilCat (talk) 20:25, 25 March 2015 (UTC)


 * That would save me from rehearsing the evidence for the transitive use of "agree", which goes back to the sixteenth century and thrives today. How about
 * This definition formed part of a treaty with the United Kingdom and other Commonwealth countries, and so is often termed international measure
 * or
 * This definition formed part of a treaty between the United States, the United Kingdom and other Commonwealth countries, and so is often termed international measure? NebY (talk) 20:56, 25 March 2015 (UTC)


 * Or that will do nicely - thanks ! NebY (talk) 21:01, 25 March 2015 (UTC)
 * You're welcome and thanks for the clean-up. -Fnlayson (talk) 21:12, 25 March 2015 (UTC)

Either of NebY's proposed alternatives would suit me, and would be better than what an intervening editor has done. As a matter of personal curiosity, I would be grateful to see some of the evidence NebY mentions, though of course not here. I can be reached via email through Wikipedia, if NebY will be so kind. J. D. Crutchfield &#124; Talk 21:06, 25 March 2015 (UTC)


 * The issue seems to be a US/British grammar thing. See here for some explanation. After reading that, I still couldn't figure out which was the correct form in American English, as it seemed awkward either way, which is why I suggested rewriting it. :) -  BilCat (talk) 21:55, 25 March 2015 (UTC)


 * Thanks for the link. J. D. Crutchfield &#124; Talk 22:00, 25 March 2015 (UTC)

Discussion of "However, in the U.S. the term "imperial" is often used colloquially in reference to the U.S. system."
I removed
 * However, in the U.S. the term "imperial" is often used colloquially in reference to the U.S. system.

Cited https://www.interexchange.org/articles/career-training-usa/2012/05/24/imperial-vs-metric-system

It was reverted. I believe the removal should stand for several reasons: --patsw (talk) 20:08, 23 November 2017 (UTC)
 * 1) interchange.org is not a reliable source and makes no claim to be one http://interchange.org/cafamintro.html
 * 2) On its face, the statement is unsupported. It is just asserted as a non-expert observation or opinion.
 * 3) So regarding colloquial usage of "imperial" to refer to United States Customary Units, my search of google and google books can't find any such claim.
 * 4) We shouldn't be giving prominence to factual claims that we believe to be incorrect.  User:Fnlayson, do you believe the claim to be correct, or you have no belief whether it is correct or not, merely presented in Wikipedia.without a WP:RS.  If you believe the claim is correct, then please support it.  If you have no opinion on its veracity, then the deletion should stand because it's made without a reliable source.


 * It was tagged as needing a better source, not simply reverted as you claim. The first move should be to tag an unreliable source if it supports an uncontroversial claim. In this case I believe the text is basically correct as stated based on what I've seen in my life.  I probably have an engineering textbook or two that incorrectly calls US customary units "imperial" units. I'll check when I get back home. The standards are somewhat different for Imperial and US units. --Finlayson (talk) 02:43, 24 November 2017 (UTC)


 * It needs a reliable source, not merely a "better" one. I believe the claim is not "uncontroversial" but incorrect and therefore should not appear in Wikipedia.  The burden in on the editor seeking to add it to provide a reliable source to include material, not for anyone to provide a source for its contradiction.  Also, bear in mind this incorrect claim contains the modifier "often".


 * Your anecdotal experience differs from mine: People who actually use the term "imperial" to refer to imperial units, even in colloquial contexts, don't confuse that system with United States Customary Units, but understand they are different. patsw (talk) 13:09, 24 November 2017 (UTC)


 * Fair enough, 'often' is probably not accurate; more like 'sometimes'. --Finlayson (talk) 22:40, 24 November 2017 (UTC)

Whenever I hear a reference to "imperial units", even in the US, it is natural to assume that if the speaker is referring to units in use in the US, they are under the mistaken impression that there is no difference or at best are referring to the two systems collectively. The cited source clearly falls into this group: showing a complete lack of awareness that US customary units and British imperial units are not quite the same system. It even claims that "Centigrade" is used, and flips without thought between "Centigrade", "Celsius" and Celcius". There are too many ways to interpret the use of "imperial" that do not support the claim in any encyclopaedic sense.  The clain also serves no real purpose.  Accordingly, I will delete the claim again as non-encyclopaedic: doubtful, anecdotal, without any reasonable source and without purpose.  —Quondum 01:40, 26 February 2018 (UTC)