I did not check all their math but the definition of the (common) pound as 0.45359237 kg was purposely made divisible by 7 to create a "metric grain." (7000 grains per av. lb) This fixes ALL the pounds, ounces, etc as having a metric root via their "grain definitions." This was agreed to in 1958 in some council of English-speaking nations (or at least their measurement labs) and adopted in the US, July 1, 1959 along with the new metric inch or foot. (I must admit that last month, we failed to celebrate the 50th anniversary of the international foot and pound) I believe the UK began using it, but took a few years to legally adopt the definition. (apparently quite a few for the troy ounce). I don't know enough UK history to know if there was an issue, or just the difference in speed of agency declaration vs Parliament passing something (which, I imagine, is about like our Congress.)
--- On Wed, 8/5/09, Pat Naughtin <[email protected]> wrote: From: Pat Naughtin <[email protected]> Subject: [USMA:45523] Re: Neat chart of English mass units To: "U.S. Metric Association" <[email protected]> Date: Wednesday, August 5, 2009, 4:45 PM Dear John, You wrote: The Weights and Measures Act of 1963 restricted use of the troy ounce to the weighing of precious metals. The Weights and Measures Act of 1985 redefined the troy ounce as 12⁄175 of 0.45359237 kilogram. Should this Troy ounce be referred to as the metric Troy ounce? It looks similar to: * the metric inch – exactly 25.4 millimetres. * the metric foot – exactly 304.8 millimetres * the metric yard – exactly 914.4 millimetres etc. Cheers, Pat Naughtin Author of the forthcoming book, Metrication Leaders Guide. PO Box 305 Belmont 3216, Geelong, Australia Phone: 61 3 5241 2008 Metric system consultant, writer, and speaker, Pat Naughtin, has helped thousands of people and hundreds of companies upgrade to the modern metric system smoothly, quickly, and so economically that they now save thousands each year when buying, processing, or selling for their businesses. Pat provides services and resources for many different trades, crafts, and professions for commercial, industrial and government metrication leaders in Asia, Europe, and in the USA. Pat's clients include the Australian Government, Google, NASA, NIST, and the metric associations of Canada, the UK, and the USA. See http://www.metricationmatters.com for more metrication information, contact Pat at [email protected] or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter to subscribe. On 2009/08/06, at 4:12 AM, John M. Steele wrote: I agree on troy ounces, not on troy pounds. I offer this: http://www.sizes.com/units/ounce_troy.htm In the English-speaking world, at least as early as the 12th century – present, a unit of mass now used only for precious metals, = 31.103 476 8 grams = 1/12 troy pound = 480 troy grains, each traditionally the mass of a grain of barley. The troy ounce is identical to the apothecaries' ounce, formerly used for drugs. It is the last unit in troy weight remaining in regular use, and then only in the United States. In the United Kingdom, when the troy pound was abolished in 1878, the troy ounce was retained for weighing precious stones and metals. The Weights and Measures Act of 1963 restricted use of the troy ounce to the weighing of precious metals. The Weights and Measures Act of 1985 redefined the troy ounce as 12⁄175 of 0.45359237 kilogram. I would also note the Wall Street Journal quotes commodities futures, and the price is per troy ounce, while contracts are 100 troy ounces (gold), 50 troy ounces (platinum) and 5000 troy ounces (silver). As none of these are divisible by 12, I believe the troy pound is no longer used in the US in a practical sense. However, since it is mentioned in NIST Handbook 44, Appendix C, it is apparently not "abolished" as it is in the UK. --- On Wed, 8/5/09, James R. Frysinger <[email protected]> wrote: From: James R. Frysinger <[email protected]> Subject: [USMA:45514] Re: Neat chart of English mass units To: "U.S. Metric Association" <[email protected]> Date: Wednesday, August 5, 2009, 1:35 PM Troy pounds and Troy ounces have long been and I believe still are used in the U.S. trading in precious metals. I believe that (Troy) pennyweights fall into that category, too. Jim John M. Steele wrote: > Maybe, superb chart of units of mess? :) > If I look at how they handled the various pounds, the av. lb and stone lead >to different quarters, hundredweights and tons, which should be set up as >separate ellipses, particularly since the long and short ton and its >subdivisions are a modern "two peoples divided by a common language" issue. > As far as I know the troy pound (and all the others except av. pound) is not >legal for trade in the US or UK, and has no real relevance. However, the troy >ounce continues for precious metals. > > --- On *Wed, 8/5/09, James R. Frysinger /<[email protected]>/* wrote: > > > From: James R. Frysinger <[email protected]> > Subject: [USMA:45511] Neat chart of English mass units > To: "U.S. Metric Association" <[email protected]> > Date: Wednesday, August 5, 2009, 11:45 AM > > > Wow! This is a superb "graph" (I call it a chart) of the units of > mass (commonly called "weight") used in England and the numerical > relationships among them. So far as I can tell it's accurate; it > jibes with the numbers and history that I know. For one, you can see > where that figure of 5760 grains per Troy pound came from! > > You will see on here 5 "pounds" listed and they all differ in size. > A similar situation in France is what led them to chuck out the > whole mess and to devise a "simple decimal system" that we now call > the metric system. > > http://en.wikipedia.org/wiki/File:English_mass_units_graph.svg > -- James R. Frysinger > 632 Stony Point Mountain Road > Doyle, TN 38559-3030 > > (C) 931.212.0267 > (H) 931.657.3107 > (F) 931.657.3108 > -- James R. Frysinger 632 Stony Point Mountain Road Doyle, TN 38559-3030 (C) 931.212.0267 (H) 931.657.3107 (F) 931.657.3108
