# What is an ounce? **URL:** \ **Category:** Factual Questions\ **Created:** [December 21, 1999, 8:00pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552 "1999-12-21T20:00:00Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [December 21, 1999, 8:00pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/1 "1999-12-21T20:00:00Z")
480 or 437.5 grains, depending upon which one you use. So what is a grain? 1/480 or 1/437.5 of whichever ounce you’re using. They obviously can’t be mutually defining without one of them being defined as something else. I realize the origin of the “grain” as a unit of weight as the result of the uniformity of whatever grain was the standard, but today, what is the standard definition of the “grain” as the building block of our system of weights? ---
**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\ **Post date:** [December 21, 1999, 8:11pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/2 "1999-12-21T20:11:00Z")
The quick answer is that there is a “standard” mass somewhere that everything else is compared to. IIRC, it is a kilogram at the National Bureau of Standards. The NBS issues calibrated masses based on the standard. ## The standard for length used to be a platinum-iridium bar with marks one meter (exactly) apart, but now the meter is defined as a certain number of wavelengths of a specified frequency of light. I don’t think there has been a similar upgrade for mass. Let’s see. I lathered and I rinsed. But did I repeat? ---
**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\ **Post date:** [December 21, 1999, 8:15pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/3 "1999-12-21T20:15:00Z")
The metric system has been searching for a better benchmark for the gram, but to no avail. They’ve found other ways to measure distance and other things, but no one’s come up with a standardized weight other than measuring it against the official kilogram in Paris. I imagine it’s the same thing with ounces. * * * “East is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does.” – Marx Read “Sundials” in the new issue of Aboriginal Science Fiction. [www.sff.net/people/rothman](http://www.sff.net/people/rothman) ---
**Author:** ![Dirty\_Devil](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@Dirty\_Devil](https://boards.straightdope.com/u/Dirty_Devil)\ **Post date:** [December 21, 1999, 8:23pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/4 "1999-12-21T20:23:00Z")
“What is an ounce?” $350 for the super-skunky green, and $160 for the cheaper Mexican brown. Oh, that wasn’t what you ment, was it? ---
**Author:** ![Dirty\_Devil](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@Dirty\_Devil](https://boards.straightdope.com/u/Dirty_Devil)\ **Post date:** [December 21, 1999, 8:25pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/5 "1999-12-21T20:25:00Z")
“What is an ounce?” $350 for the super-skunky green, and $160 for the cheaper Mexican brown. ## Oh, that wasn’t what you ment, was it? “Dope will get you through times of no money better than money will get you through times of no dope.” ---
**Author:** ![Dirty\_Devil](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@Dirty\_Devil](https://boards.straightdope.com/u/Dirty_Devil)\ **Post date:** [December 21, 1999, 8:27pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/6 "1999-12-21T20:27:00Z")
Damn, I guess all that dope made me forget that I already posted a reply. ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [December 21, 1999, 8:52pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/7 "1999-12-21T20:52:00Z")
Ah, but is that a Troy ounce? For some reason they seem to offer pot in troy ounces instead of regular ounces… ---
**Author:** ![Boris\_B](https://avatars.discourse-cdn.com/v4/letter/b/fbc32d/32.png) [@Boris\_B](https://boards.straightdope.com/u/Boris_B)\ **Post date:** [December 21, 1999, 9:35pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/8 "1999-12-21T21:35:00Z")
I think that’s so they can get you with the old trick, “What’s heavier, an ounce of feathers or an ounce of…” ---
**Author:** ![NonTarheel](https://avatars.discourse-cdn.com/v4/letter/n/edb3f5/32.png) [@NonTarheel](https://boards.straightdope.com/u/NonTarheel)\ **Post date:** [December 21, 1999, 11:15pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/9 "1999-12-21T23:15:00Z")
> [@](#): > > The metric system has been searching for a better benchmark for the gram, but to no avail. They’ve found other ways to measure distance and other things, but no one’s come up with a standardized weight other than measuring it against the official kilogram in Paris. I’m aware of the Standard Kilogram, too, but I thought the original definition of 1 gram was 1 cm^3 of distilled water at a given temperature and pressure. Seems a lot easier to deal with than keeping some lump of metal under lock and key in Paris. Gets around the messy mass/weight distinction, too. And how did the Metric System Gods decide how much the Standard Kilogram was going to weigh in the first place, if not for 1cm^3 = 1g? I’ll bet you could make a good James Bond movie about someone trying to sabotage or steal the Standard Kilogram. ---
**Author:** ![pluto](https://avatars.discourse-cdn.com/v4/letter/p/f08c70/32.png) [@pluto](https://boards.straightdope.com/u/pluto)\ **Post date:** [December 21, 1999, 11:35pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/10 "1999-12-21T23:35:00Z")
Just a quibble **Non** , but there’s a difference between a definition and a standard. ## I presume they did, in fact, create the standard kilogram based on the definition, but IMHO it’s a lot easier to put a certified weight on a scale than an exact volume of water at a given temperature and pressure. Let’s see. I lathered and I rinsed. But did I repeat? ---
**Author:** ![system](https://global.discourse-cdn.com/straightdope/original/2X/e/e489c3b7d8fce19c4b355dd4fc3f88cc39c34b87.png) [@system](https://boards.straightdope.com/u/system)\ **Post date:** [December 22, 1999, 4:42am UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/11 "1999-12-22T04:42:00Z")
The defining weight measurement in the English system is the pound, which is divided in 16 ounces. I don’t whether the pound is defined as the weight of of a pint (of water?), or if a pint is defined as the volume of a pound (of water?), but have heard that “A pint’s a pound the world round”. Relating to grains - ever wonder why aspirin, tylenol, iron & other common meds come in 325 mg tablets? It’s because 1 grain = 65 gm, so a 5-grain tablet would have 325 mg of active medicine. * * * Sue from El Paso Experience is what you get when you didn’t get what you wanted. ---
**Author:** ![John\_W.Kennedy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_w.kennedy/32/1031_2.png) [@John\_W.Kennedy](https://boards.straightdope.com/u/John_W.Kennedy)\ **Post date:** [December 23, 1999, 10:25pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/12 "1999-12-23T22:25:00Z")
Actually, that “a pint’s a pound” thing is grossly inaccurate. An Imperial pint was not the same as an American Liquid Pint, which is not the same as an American Dry Pint. Not even approximately. And the Imperial and American pounds weren’t exactly the same, either. The difficulty in exactly measuring a quantity of water is the reason that a liter is no longer defined as a cubic decimeter. A liter is the volume of a kilogram of water, and it’s different from a cubic decimeter somewhere in the 4th or 5th digit. The pound avoirdupois is actually defined in the USA as the weight, under standard gravity, of a mass of exactly .4535924277 kg. However, at least as of the 60’s, the troy pound was still defined by a physical weight in Washington. * * * John W. Kennedy “Compact is becoming contract; man only earns and pays.” – Charles Williams ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [December 23, 1999, 11:21pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/13 "1999-12-23T23:21:00Z")
Is there such a thing as a troy ton? ---
**Author:** ![John\_W.Kennedy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_w.kennedy/32/1031_2.png) [@John\_W.Kennedy](https://boards.straightdope.com/u/John_W.Kennedy)\ **Post date:** [December 24, 1999, 3:05pm UTC](https://boards.straightdope.com/t/what-is-an-ounce/5552/14 "1999-12-24T15:05:00Z")
Troy \\code:\\\ 24 grains = 1 pennyweight 480 grains = 20 pennyweights = 1 Troy ounce 5760 grains = 240 pennyweights = 12 Troy ounces = 1 Tr. pound ```auto Apothecaries'
code:
20 grains = 1 scruple
60 grains = 3 scruples = 1 apothocaries' dram
480 grains = 24 scruples = 8 apothocaries' drams = 1 ap. ounce
5760 grains = 288 scruples = 96 apothocaries' drams = 12 ap. ounces = 1 ap. pound

```

Avoirdupois (minor)

> code:
> * * *
> 
> ```
> 27 11/32 grains = 1 avoirdupois dram
> 437 1/2 grains = 16 avoirdupois drams = 1 av. ounce
> 7000 grains = 256 avoirdupois drams = 16 av. ounces = 1 av. pound
> 
> ```auto
> 
> Avoidrupois (Imperial major)
> 
code:
> 14 pounds = 1 stone
> 28 pounds = 2 stone = 1 quarter
> 112 pounds = 8 stone = 4 quarters = 1 hundredweight
> 2240 pounds = 160 stone = 80 quarters = 20 hundredweight = 1 ton
> 
> ```
> 
> Avoirdupois (US major)
> 
> > code:
> > * * *
> > 
> > ```
> > 100 pounds = 1 hundredweight
> > 2000 pounds = 20 hundredweight = 1 ton
> > 
> > ```auto
> > 
> > The Imperial ton is also known as the "long" or "gross" ton. The US ton is also known as the "short" or "net" ton. Same for hundredweights.
> > 
> > There is a further very small difference between the US and Imperial units due only to a slight variance between the historic standard pounds.
> > 
> > The "tonne" is an (irregular) alternate name for the megagram.
> > 
> > ------------------
> > John W. Kennedy
> > "Compact is becoming contract; man only earns and pays."
> > -- Charles Williams
> > ```
> > ```
> ```