Dear Gene,
Thanks for your comments. I appreciate your thoughts and I have
interspersed some comments within your email.
On 2010/04/25, at 04:26 , <[email protected]>
<[email protected]> wrote:
Pat,
Here are some comments on your analysis of the blog:
The choice is "What is the optimum SI *Prefix* to use for a
particular application?" not "What is the choice of SI Unit for that
particular application?"
Point taken. I tend to use the expression 'SI unit' as it is used
casually rather that your more precise expression. I will keep this in
mind in future.
If one accepts that SI is superior to any other "collection of
miscellaneous units," the "complete set of coherent SI Units" is
already fully prescribed. Only the SI prefixes remain to be
selected for various applications.
Agreed, but it is an absolutely essential step to choose the best
prefixes for a particular metrication process especially if you are
concerned about the metrication process rather than transmitting a
definitive knowledge of the metric system.
As you know I concentrate on the metrication process as I believe that
it has more significance to the worlds of building, commerce,
engineering, health, manufacturing, medicine, science, and to life in
general. A deep knowledge of the metric system with its technical
definitions and its mathematical coherence has a place in academia but
I do not usually explore this too far as I keep returning to the
metrication process because I think that is more important to the
world at this time.
We are all aware that you recommend the prefix "milli" rather than
the prefix "centi" for all applications to the unit "meter" BUT the
SI unit is "meter" in both cases.
Let me correct your statement. I do not recommend that you do not use
the centimetre. What I do is state as strongly as I can that I have
never, repeat never, observed a metrication process that goes
smoothly, efficiently, and above all, quickly if you decide to use
centimetres. That said, I do not recommend what decision you should
make – that is entirely up to you. You could choose a metrication
process where the upgrade is made in as little as a day and almost
always under two years (with millimetres) or you can choose a
transition process that might last for more than 100 years (with
centimetres). It is your choice; I make no recommendation.
Others, including myself, recommend the freedom to select the prefix
centi as in "centimeter" for human clothing measurements and other
applications that do not require the convenience offered by the
prefixes milli, micro, nano, etc.
As I said it is your choice. I worked in the textile industry for
about 10 years so I directly observed the difficulties that
centimetres bring to textile workers. 'There are 'metric conversion'
tables of various authenticity littered throughout textile mills.
These tend to continue the use of inches but now with the addition of
metric units and also the continuation of textile industry jargons
(such as picks, denier, micron, tex, gsm, mommes, etc.), The
centimetre brings with it common or vulgar fractions as well as
decimal fractions and it also brings those delightful decimal points
for factory workers, often with quite low numeracy skills, to slide
about. Your statement about the centimetre for clothing sizes refers,
I think, to retail sizes and not to the nightmare of composite inch/
metric/jargon measures and hence unnecessarily complex measurements in
the textile factories. And this all happens alongside the textile
machinery engineers, maintenance carpenters and plumbers who work
solely in millimetres – it makes for some fun, even heated –
conversations in the factory staff room.
Gene.
By the way, Gene, you have stirred my stumps! I will attempt to write
something – a short essay perhaps – about what that works and what I
have observed that doesn't work when you lead a metrication process.
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 [email protected]
or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter
to subscribe.
---- Original message ----
Date: Sat, 24 Apr 2010 20:23:22 +1000
From: Pat Naughtin <[email protected]>
Subject: [USMA:47256] Metrication in Africa
To: "U.S. Metric Association" <[email protected]>
Cc: USMA Metric Association <[email protected]>
Dear All,
I just found this
page
http://course-civil-engineering.blogspot.com/2010/04/how-metric-system-was-introduced-in.html
...
Pat's comments (not necessarily Pat's recommendations):
...choose just one single unit if you
can.
For example,
All drinks will be measured in millilitres.
All buildings will be measured in millimetres.
...
In the teaching institutions, on the other hand, the
rules were (and still are ?):
1 Choose as many units as you possibly can.
...
2 Encourage conversion between all the metric
system units that you have chosen. Don't forget to
include all the ones you have made up.
