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Hi Thomas,
I think some of your information is dated. The primary standards have
long passed the metal rod stage. The now use the wavelenght of some
natural frequency. I think it used to be Cesium, but this stuff is
always evolving. If I go to http://www.onlineconversion.com/volume.htm,
they tell me that 1 cc = 1 ml. so the units may have been adjusted
slightly to get them to work out. Also the relationship between the
units is more straightforward in metric. The choice for what to use
for the length of the meter was more or less arbitrary.
I read an interesting book a while back called "Measuring America" by
Andro Linklater. Along with an explanation of how the country was
surveyed, there is a lot of information about the development of
measurement systems including metric and the events surrounding those
developments. One of the things I was most surprised about was that
Thomas Jefferson was a proponent of a decimal system that was less
arbitrary than the French system. For example the unit of length was
tied directly to the unit of time by specifying the length of a 1 second
pendulum as the basic unit of length and 1 inch = 1/10 foot
Weight: 1 oz = 1 cu in of rainwater and 10 ounces = 1 lb
Volume: 1 bushel = 1 cu ft
Thomas J. didn't get his decimal system implemented, but he did manage
to get the currency decmalized so we have pennies and dimes instead of
pence and shillings or pieces of eight or whatever.
Bob W.
On Sat, 25 Nov 2006 18:12:04 -0800
Steve Thomas <steve@stevet.net> wrote:
> I don't get it. All measurement systems are arbitrary. The
> "English" system certainly came from some odd roots. But so did the
> railroad track gauge (it was the width of a horse drawn wagon
> track.) And guess what else? The Space Shuttle booster rockets were
> designed around the same gauge so it could be shipped to its final
> destination. The metric system was designed around what they thought
> was the circumference of the earth. They got it wrong. And, 1 cc is
> not the same as 1 ml., though that was the intent. Now, all
> measurements are based on a metal rod, or other device, residing in a
> refrigerator at a constant temperature in the National Weights and
> Measures office for the US and somewhere in France for metric
> measurements.
>
> OK, the SAE system may be a little convoluted, but once you learn it,
> it works just fine. Oh, I forgot, we should change just because the
> Europeans use it. Should we also adopt soccer as our national
> pastime just because the "rest of the world" sees soccer as their
> national pastime? I mean, almost no one adopts our version of
> football. Just because "they" do it is not an a-priori reason do to so.
>
> Will we eventually migrate over to metric de-facto even though we
> have rejected a de-juris solution? Maybe. But in the interim, SAE
> works just fine, and in the absence of a compelling economic reason
> to do so, if it ain't broke, don't fix it.
>
> Best Regards,
>
> Steve
>
> ____________________________________________________________________
>
>
> On Nov 25, 2006, at 5:40 PM, Bulent Aliev wrote:
>
> >> I just think it is embarrassing that the US cant seem to adopt the
> >> international system...
>
>
> --
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