On 2009/12/28, at 01:04 , John Frewen-Lord wrote:
Well, it was a bit interesting, if somewhat childlike in its
presentation.
Pity that in the last segment, when explaining that there are 1000
m in 1 km, they sort of treated the m and the km as two discrete
units, rather than simply one unit with a prefix.
Still, progress of sorts! Interesting that NASA seems to be
promoting this, when we all know that they are as much the villain
as anyone in resisting the US's conversion to the metric system.
Dear John,
I agree with you about the distinction between metres and kilometres.
I am also intrigued by the NASA sponsorship.
I also had a concern about the underlying assumption that 'there are
two systems of measurement' as I don't think that this is true.
There is certainly a metric system but to my way of thinking there
never was a single previous system of measuring units. My analysis of
the old pre-metric situation is that they were more or less randomly
generated collections of measuring words that were more or less
associated with measuring activities.
As an example, consider the inch.
Prior to the defining of the metric inch, in 1959, as exactly 25.4
millimetres, the inch had many different definitions that included the
width of a thumb, the length of three grains of barley, dry and round,
placed end to end, lengthwise, 1/3 of a palm, 1/4 of a hand, 1/12 of
the foot of St Paul's, and 1/36 of the distance between King Henry I
of England's nose and his thumb.
More formally, legal definitions of the UK inch have included:
1814 three grains of sound ripe barley being taken out the middle of
the ear, well dried, and laid end to end in a row
1819 A preliminary yard was made in anticipation of the Imperial yard
in 1824. This yard has been precisely measured as 39.3694 inches to a
metre which means that each inch was about 25.4004379 mm.
1824 1/36 of an Imperial yard. This yard was precisely measured as
914.398416 metres giving an inch of 25.399956 mm. Note this was the
first Imperial measure; earlier measures were not legally 'Imperial'.
1834 The British Standard yard was destroyed in a fire when the
British Houses of Parliament burnt down. The inch was destroyed along
with the yard.
1841 New standard yards were made. Unfortunately, as a standard, the
metal chosen for these standard yards (Baily's metal) began to shrink.
In:
* 1895 the inch was 25.399978 mm
* 1922 the inch was 25.399956 mm
* 1932 the inch was 25.399950 mm
* 1947 the inch was 25.399931 mm (See http://home.att.net/~numericana/answer/units.htm
and search for nara)
1842 a standard inch measure was kept in the Exchequer chamber,
Guildhall, and that was the legal definition of the inch.
1855 1/36 of a standard yard defined as the length of a 36 inch yard
derived from a seconds pendulum beating 86 400 times between two
meridians of the Sun. The pendulum was held in a vacuum in a
temperature controlled chamber at sea level in Greenwich, London. The
length of this pendulum was 39.1392 inches (about 994.1357 mm).
1878 A new physical standard yard was made and this remained the UK
Imperial standard until 1964.
1964 The Uk legally adopted the metric inch, of exactly 25.4 mm, as
the Imperial standard inch.
During this time, while the length of the metre and hence the
millimetre remained constant, there has been a wide range of changing
values for the different UK inches – hardly a system!
Note that I have not included all of the other inches that each have
multiple definitions hence multiple different lengths. Here are some
of their names: angulam, anguli, duim, hüvelyk, palec, polegada,
polegartum, police, pouce, pulgada, pulgar, thumb, tome, tommel, and
tumme.
And I have not referred to the changing definitions of the legal inch
in the USA at all. This is too complex for me.
Please note that the inch is only one example of old pre-metric
measuring words. Every old pre-metric measuring word can be similarly
analysed. You could begin with: foot, pound, bushel, barrel, ton, etc.
etc.
To conclude, I find no evidence for any system before the metric
system formulation as the Système Internationale d'Unités. I have not
ignored fps, cgs, mksA, foot-slug-second, etc. I simply regard them as
being attempts to form a system that failed because they were
incomplete and not coherent.
Cheers,
Pat Naughtin
Author of the ebook, Metrication Leaders Guide, that you can obtain
from http://metricationmatters.com/MetricationLeadersGuideInfo.html
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 pat.naugh...@metricationmatters.com
or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter
to subscribe.
----- Original Message -----
From: Pat Naughtin
To: U.S. Metric Association
Sent: Sunday, December 27, 2009 5:36 AM
Subject: [USMA:46304] YouTube metric
You might find this interesting:
http://www.encyclopedia.com/video/DQPQ_q59xyw-metric-standard-measurement-systems.aspx
Cheers,
Pat Naughtin
Author of the ebook, Metrication Leaders Guide, that you can obtain
from http://metricationmatters.com/MetricationLeadersGuideInfo.html
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 pat.naugh...@metricationmatters.com or
to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter
to subscribe.
