Dear Martin,
I think that the development of rational decimal world geography
happened at a separate time to the development of time zones. The
first happened in the 1790s and the second happened in the 1880s
following the development work done in the 1870s by Sir Sandford
Fleming to resolve problems with Canadian Railways.
I don't think that we can blame it on our duodecimal clocks as the two
events were fairly far apart.
By the way, some years ago I had the opportunity to speak to the
Canadian Metric Association and they arranged for me to speak in the
Sir Sandford Fleming Lecture Hall at the University of Toronto.
Cheers,
Pat Naughtin
Author of the ebook, Metrication Leaders Guide, see
http://metricationmatters.com/MetricationLeadersGuideInfo.html
Hear Pat speak at: http://www.youtube.com/watch?v=_lshRAPvPZY
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 2010/06/08, at 04:55 , Martin Vlietstra wrote:
There was actually some logic behind the nautical mile. In the
1870’s when time zones were first being introduced a choice had to
be made regarding the prime meridian – there were two candidates –
Greenwich and the French equivalent. At the time the best maps were
British and that swung the day. Also, clocks had 12/24 hours, not
10, so 360° was a better choice than 400.
Ther you are – blame it on our duodecimal clocks.
From: [email protected] [mailto:[email protected]] On
Behalf Of Pat Naughtin
Sent: 07 June 2010 06:37
To: U.S. Metric Association
Subject: [USMA:47527] Nautical measures
On 2010/06/06, at 17:12 , Martin Vlietstra wrote:
For many years the Daily Telegraph quoted the height of high tide at
Dover in feet without the benefit of a metric conversion, even
though the height indicator at the Dover docks was only in metres,
the admiralty charts were in metres and the published tide tables
were in metres.
Dear Martin,
One of the (several) reasons that the French metric committee chose
to use the Earth as a standard for the length of the metre was that
they lived in an age when shipping and world exploration were
extremely important issues. They intended that the measuring of
angles in grades and the measuring of distances in metres and
kilometres would drastically reduce the complexity of nautical
calculations.
Consider a quadrant of the Earth divided decimally.
1 quadrant = 100 grade = 10 000 kilometres
0.1 quadrant = 10 grade = 1000 kilometres
0.01 quadrant = 1 grade = 100 kilometres
0.001 quadrant = 0.1 grade = 10 kilometres
0.000 1 quadrant = 0.01 grade = 1 kilometres
etc.
Unfortunately sailors decided not to go with the simplicity of the
decimal metric system so the transition to the metric system didn't
work so far (from 1770 till 2010).
People 'who go to the sea in ships' still cling to the pre-1770
measuring words. They continue to use:
nautical miles for distance
knots for for wind speed
knots for vessel speed
feet for vessel length
inches for rope diameter
etc.
Perhaps your example is simply another example of irrational
conservatism.
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.
