# The USA and the Metric System.

**URL:** <https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672>\
**Category:** Great Debates\
**Created:** [November 17, 2018, 9:15am UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672 "2018-11-17T09:15:26Z")\
**Posts on this page:** 19\
**Page:** 8

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**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\
**Post date:** [November 22, 2018, 3:24am UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/141 "2018-11-22T03:24:17Z")

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> [@Batano](#):
>
> I assume you have never used a British, Canadian, or Australian cookbook.

We cook in Fahrenheit in Canada.

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**Author:** ![Uzi](https://avatars.discourse-cdn.com/v4/letter/u/91b2a8/32.png) [@Uzi](https://boards.straightdope.com/u/Uzi)\
**Post date:** [November 22, 2018, 3:41am UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/142 "2018-11-22T03:41:13Z")

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> [@rat\_avatar](#):
>
> Same thing but that was a bad choice of examples
> 
> 5280/10 = 528 feet ~ 500 feet per .1 mile.

I’m probably safe in assuming that most people won’t know that.

> [@Cheesesteak](#):
>
> Nobody should be looking at their odometer to decide when to move over for an exit. At highway speeds, 500ft goes by fast enough that you’ve missed the exit by the time you glance down at the odometer.

Should I not look at my oil pressure, temp or gas gauges as well? Use the tools at your disposal to manage how you drive. If you don’t have a GPS, you can use the odometer in a similar fashion. But I agree that at 500’ you should be focused on getting in the correct lane and not trying to break down tenths into smaller units on your odometer!🙂

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**Author:** ![rat\_avatar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rat_avatar/32/255_2.png) [@rat\_avatar](https://boards.straightdope.com/u/rat_avatar)\
**Post date:** [November 22, 2018, 4:20am UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/143 "2018-11-22T04:20:40Z")

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> [@Uzi](#):
>
> I’m probably safe in assuming that most people won’t know that.

Units of measure are not made to appease those who are paranoid of learning math. No number system is going to fix our cultural problems.

Americans are bad at math because they don’t make the effort to learn, and are actively encouraged to not learn by a society that makes it OK to be ignorant about math.

> **[US Math Achievement: How Bad Is It?](https://www.psychologytoday.com/us/blog/everybody-is-stupid-except-you/201211/us-math-achievement-how-bad-is-it)**
>
> Three eye-opening studies paint a sobering picture but may point to a solution

> [@](#):
>
> In all, 77% of the students seemed to believe that math was not something that could be figured out, or that made sense. It was just a set of procedures and rules to be memorized. This is, of course, exactly the opposite of true.

Like anything in life unless you try to learn something you never will.

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**Author:** ![Uzi](https://avatars.discourse-cdn.com/v4/letter/u/91b2a8/32.png) [@Uzi](https://boards.straightdope.com/u/Uzi)\
**Post date:** [November 23, 2018, 10:00am UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/144 "2018-11-23T10:00:46Z")

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> [@rat\_avatar](#):
>
> Units of measure are not made to appease those who are paranoid of learning math. No number system is going to fix our cultural problems.

But having to do math on 1760 yards or 5280 feet as sub-units of a mile is ridiculous. 1000 meters in a kilometer is undeniably easier.

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**Author:** ![UltraVires](https://avatars.discourse-cdn.com/v4/letter/u/ecccb3/32.png) [@UltraVires](https://boards.straightdope.com/u/UltraVires)\
**Post date:** [November 23, 2018, 12:28pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/145 "2018-11-23T12:28:31Z")

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> [@Uzi](#):
>
> Should I not look at my oil pressure, temp or gas gauges as well? Use the tools at your disposal to manage how you drive. If you don’t have a GPS, you can use the odometer in a similar fashion. But I agree that at 500’ you should be focused on getting in the correct lane and not trying to break down tenths into smaller units on your odometer!🙂

I know nobody who uses their odometer to adjust to: Exit One Mile, 1/2 mile, 1/4 mile, 500 feet to determine the amount of time that they have to move over. If you wish to exit, those signs tell you that you should move over, respectively: soon, very soon, now, and right fucking now if you can safely.

In metric countries, do you really see a next exit 1 km sign, lets say, see that you are going 100km per hour and use your odometer and determine that you have 37.2 seconds to get in the correct lane?

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**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\
**Post date:** [November 23, 2018, 3:23pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/146 "2018-11-23T15:23:21Z")

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> [@Chronos](#):
>
> … How about the pound: Is that Avoirdupois, or Troy? …

Here you have an answer to the unanswerable question, _which weighs more, a pound of feathers or a pound of gold_? Clearly the pound of feathers weighs more. Do it in Kg and the answer is the uninteresting “same”.

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**Author:** ![rat\_avatar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rat_avatar/32/255_2.png) [@rat\_avatar](https://boards.straightdope.com/u/rat_avatar)\
**Post date:** [November 23, 2018, 3:34pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/147 "2018-11-23T15:34:44Z")

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> [@eschereal](#):
>
> Here you have an answer to the unanswerable question, _which weighs more, a pound of feathers or a pound of gold_? Clearly the pound of feathers weighs more. Do it in Kg and the answer is the uninteresting “same”.

The avoirdupois pound, which the United States customary units pound and the UK imperial units of measure pound are defined off, of is a unit of mass. The US pound has always been a unit of mass and the belief that it isn’t is a persistent urban legend. In fact the US pound has been directly defined off of the kilogram after the Mendenhall Order of 1893.

The derived unit of pound-force or lbf or lb[sub]f[/sub] is often marked as pounds or lbs because most of us will only live on the Earth, but the base unit of _pound_ is and always has been a unit of mass.

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**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\
**Post date:** [November 23, 2018, 4:24pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/148 "2018-11-23T16:24:13Z")

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Interestingly the US has always used metric currency. I am puzzled why you didn’t adopt 240 cents to the Dollar (in line with the British Pound:Penny) on the grounds that it has loads more sub-multiples than 100.

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**Author:** ![rat\_avatar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rat_avatar/32/255_2.png) [@rat\_avatar](https://boards.straightdope.com/u/rat_avatar)\
**Post date:** [November 23, 2018, 4:42pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/149 "2018-11-23T16:42:53Z")

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> [@bob\_2](#):
>
> Interestingly the US has always used metric currency. I am puzzled why you didn’t adopt 240 cents to the Dollar (in line with the British Pound:Penny) on the grounds that it has loads more sub-multiples than 100.

The responsible parties US government actually tried to, and actually partially did adopt the Metric system really early

> **[nbsspecialpublication447.pdf](https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication447.pdf)**

The troy pound has it’s roots in the Hanseatic League which a quasi-governmental alliance of merchants based on the shores of the Baltic, who had special trading rights in England.

As the US didn’t adopt the metric system at the time they had to choose one of the pounds used in the UK at the time to avoid having a similar problem and they had the following ones to pick from:

[ul]  
[li]Troy pound: 12 ounces each of 480 grains, or 5760 grains[/li][li]Hanseatic League pound: 15 troy ounces, or 7200 grains[/li][li]Pound of 16 troy ounces, or 7680 grains[/li][li]Pound Avoirdupois: 16 ounces each of 437.5 grains, or 7000 grains [/li][li]London pound: 15 ounces of 450 grains each, or 6750 grains[/li][li]Tower pound: 12 ounces each of 450 grains, or 5400 grains[/li][/ul]

As Troy measurements were only used in gold and gemstones they went with the Pound Avoirdupois which was based on an easily divisible number yet was in common use and was related to the older unit of measure from Rome in the middle ages. The Pound Avoirdupois was chosen from a menu and not homemade.

Had the metric system been more stable and established we would have probably adopted it at the time but we needed to set standards.

Ironically being an early adopter is partially why we still haven’t fully moved over. We defined our base units off the Metric units very early and thus have zero loss in accuracy or precision when using conversion factors. This means that taxes and tariffs are accurately calculated and the government has less financial motivation to press for changes.

The real question is why did the UK deal with that messy pile of pounds for so long?

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**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\
**Post date:** [November 23, 2018, 5:58pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/150 "2018-11-23T17:58:23Z")

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As far as the distance thing goes, I envision a day several decades in the future when all the road signs are gone, replaced by overlapping long-range RFID-ish nodes. Your vehicle will be equipped with a node reader that acquires information and provides it to you in the manner of your choosing. If you are operating the vehicle yourself, manually, there might be a graph-bar-like image that runs down to let you know you are getting close to whatever thing you need to deal with and how the lanes are laid out, and stuff. Of course, most people will use auto-pilot, so those numbers will not matter.

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**Author:** ![rat\_avatar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rat_avatar/32/255_2.png) [@rat\_avatar](https://boards.straightdope.com/u/rat_avatar)\
**Post date:** [November 23, 2018, 6:21pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/151 "2018-11-23T18:21:47Z")

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Except for the people that create, maintain, and configure those systems. Unit standards are far more about taxation and trade than consumers.

Oddly enough while I prefer we adopt SI, for distances on Earth the Nautical Mile is the superior unit of length.

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**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\
**Post date:** [November 23, 2018, 6:45pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/152 "2018-11-23T18:45:59Z")

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> [@rat\_avatar](#):
>
> The real question is why did the UK deal with that messy pile of pounds for so long?

Inertia and a lack of incentive. As computers became more established and the complications of Pounds Shillings and Pence became more apparent, a movement to decimal currency gained momentum. Predictably the main objections related to the inevitable ‘rounding up’ of prices that retailers would take advantage of.

I predict that the smaller copper coins will be quietly dropped from commercial use in the next decade, while mericans carry on grimly hanging on to their almost worthless Dollar bills.

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**Author:** ![rat\_avatar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rat_avatar/32/255_2.png) [@rat\_avatar](https://boards.straightdope.com/u/rat_avatar)\
**Post date:** [November 23, 2018, 7:00pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/153 "2018-11-23T19:00:15Z")

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> [@bob\_2](#):
>
> Inertia and a lack of incentive. As computers became more established and the complications of Pounds Shillings and Pence became more apparent, a movement to decimal currency gained momentum. Predictably the main objections related to the inevitable ‘rounding up’ of prices that retailers would take advantage of.
> 
> I predict that the smaller copper coins will be quietly dropped from commercial use in the next decade, while mericans carry on grimly hanging on to their almost worthless Dollar bills.

I meant the multiple units of weight.

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**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\
**Post date:** [November 23, 2018, 7:05pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/154 "2018-11-23T19:05:24Z")

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> [@bob\_2](#):
>
> I predict that the smaller copper coins will be quietly dropped from commercial use in the next decade, while mericans carry on grimly hanging on to their almost worthless Dollar bills.

Please put those in a plain brown envelope and mail to me. 😛

Now, pennies, yes _they_ are worthless.

The brits have Coin denominations as follows: 1p, 2p, 5p, 10p, 20p, 50p, £1 and £2. Since a £ is only worth a trifle more than a $, also send me all your 10p, 20p & 50 coins, since they are also worthless.

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**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\
**Post date:** [November 23, 2018, 7:35pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/155 "2018-11-23T19:35:54Z")

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Well, a nice crisp plastic ten-pound note and one of our Pound coins would buy me 14 dirty crumpled Dollar bills as of today.

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**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\
**Post date:** [November 23, 2018, 7:48pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/156 "2018-11-23T19:48:43Z")

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> [@bob\_2](#):
>
> Well, a nice crisp plastic ten-pound note and one of our Pound coins would buy me 14 dirty crumpled Dollar bills as of today.

In addition it can be used in the place of a turntable needle. I’ve confirmed this with some tracks that I don’t particularly care about, although I wonder if any old paper/linen would do just as good as the new plastic notes.

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**Author:** ![clairobscur](https://avatars.discourse-cdn.com/v4/letter/c/839c29/32.png) [@clairobscur](https://boards.straightdope.com/u/clairobscur)\
**Post date:** [November 23, 2018, 9:40pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/157 "2018-11-23T21:40:43Z")

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> [@rat\_avatar](#):
>
> Found the name for the original _metric unit of dry volume_, the _stere_ which was one cubic meter just like the current accepted derived SI unit of volume.
> 
> While lacking the name conflict with ounce and fluid ounce, that complexity did exist. There was a conflict with “cubic meters” and differing industry meanings related to woodpiles etc… which caused it to be dropped for the derived unit of volume; yet people continue to use the old, dropped unit for liquid volume or liter.

The stere is also still used for wood. Or at least was when I was younger. It’s been a very long while since I had last to care about firewood.

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**Author:** ![rat\_avatar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rat_avatar/32/255_2.png) [@rat\_avatar](https://boards.straightdope.com/u/rat_avatar)\
**Post date:** [November 23, 2018, 10:46pm UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/158 "2018-11-23T22:46:29Z")

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> [@clairobscur](#):
>
> The stere is also still used for wood. Or at least was when I was younger. It’s been a very long while since I had last to care about firewood.

Interesting that it is still in use but these basic quantities have long lives,

For liquid measure the Roman base unit was the _sextarius_ which is estimated to be somewhere between the US and Imperial pints. The funny thing is that the _sextarius_ was a six pack of _congius_ which was 1/8 of a Roman cubic foot or the _amphora_

Well really sextarius = ​1⁄48 of a cubic foot, but they got to that weird fraction by having six packs. 😉 The Roman _sextarius_ was probably based on Egyptian _hnw_ (volume) which was about 1 _mina_ of water (Sumerian weight).

So the fluid measures seem fairly consistent until the dry measures seem to diverge later, probably driven by trade needs and taxing or perhaps the regional variation of the “grains” used as a unit of mass.

Anyway it took a revolution to change things, but even then the 1/2 liters is close to the same volume as one pint, sextarius, hnw… If I had to guess more people cared more about beer and wine measurements being accurate than anything else in their day to day life.

(I still dream of a mostly SI world)

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**Author:** ![Uzi](https://avatars.discourse-cdn.com/v4/letter/u/91b2a8/32.png) [@Uzi](https://boards.straightdope.com/u/Uzi)\
**Post date:** [November 24, 2018, 1:53am UTC](https://boards.straightdope.com/t/the-usa-and-the-metric-system/824672/159 "2018-11-24T01:53:07Z")

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> [@UltraVires](#):
>
> If you wish to exit, those signs tell you that you should move over, respectively: soon, very soon, now, and right fucking now if you can safely.

Because not every place has 10 signs to hold your hand and tell you when to exit. And not every time you use an odometer has to do with an off-ramp e.g Turn left for raspberries in 1.2km.

> [@](#):
>
> In metric countries, do you really see a next exit 1 km sign, lets say, see that you are going 100km per hour and use your odometer and determine that you have 37.2 seconds to get in the correct lane?

I guess you could do that…or you could just glance at your odometer and see that you have 400m left, 300m, 200m, etc.

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