>But let's face it -- going metric at sea never made much practical common
>sense to me. It's awkward, and you can't run to a navigational chart and
>quickly figure out where some thing, or some place at sea is, or how long it
>is going to take to get there without wasting time calculating pointless
>conversions while Cook's petrels are getting away.

Uhh...but isn't that simply because degrees of latitude aren't metric? In
other words, an nm being a minute means, from the metric point of view,
that a unit useful for navigation be proposed which is equal to a km.

After all, there is nothing magic about base 60, which is where the
geometric divisons have been derived. Must've been counting the
fingers and toes of the whole damned harem when that base was decided
upon!

The meter is, after all, derived from a base 10 division of
the (then understood) diameter of the earth, no? My understanding
is that the entire metric system lies upon the definition of the
meter, which lies upon a division of the circumferance of the earth.
Exactly as the nautical mile does, but based on base 10 rather than
base 60.

Why should divisions by multiples of 60 hold sway over divisions
by multiples of 10, other than the existence of current charts? Same
arguments apply everywhere, including the decisions made in the past to
support use of the metric system in technical journals. The French
adopted base 10 because it is so easy to work with, much as they
adopted the guillotine as it was so much more humane than other,
contemporary means of execution.

All measurement systems are self-referential.

This bears repeating: All measurement systems are self-referential.
Actually, both of the currently competing measurement systems, I
should say...

he metric system is amazingly consistent in this regard,
with a power-of-10 division of the Earth's circumference extending
to the basic measure of mass (centigram) and energy (calorie and
Calorie). How well does the nautical mile extend to the quart,
etc, despite sharing a heritage in being based upon a (base 60,
though) division of circumference? One can easily argue that the
French saw the logic of the nautical mile, being based upon a more
or less immutable physical figure (the circumferance of the earth),
and simply switched bases and moved on from there.

In today's computer
world, the whole issue is actually moot, since we can accomodate
arcane systems, like knots and nautical miles, via simple software.
The problem is more physical, i.e. my metric wrenches not
fitting my American plumbing fittings. Software is costless,
once written and incorporated in standard tools. Wrenches etc
are not free.

The supremacy of the English system on water is more due to
naval supremacy than intellectual supremacy, no? Of course naval
charts are cast in English terms, this has been an oxymoron since
Trafalgar, I should think. Or before...Trafalgar was sort of
like a victory in a copyright battle from the units standards
point of view. The French fleet sunk, the knot swam.

>On land (bravo!! Canada!) the metric system is logical and makes perfect
>sense. Under normal operating situations, vessel navigation equipment are
>programed to calculate distances in nautical miles and there are even pocket
>calculators specifically for that purpose as well. Further, a vessel's speed
>is calculated in knots, and one knot = one nautical mile per hour. Metric,
>meters, kilometers, etc. is just way to complicated unless you have some fine
>tuned specific research objective that demands it and everything can be
>programed to do that.

Well, thanks for the confirmation that one knot = one nautical MPH.

But, really, the claim that metric is "just way too complicated" has
more to do with street signs, ... uhhhh.... naval tradition than
anything.

Given different results at Waterloo and Trafalgar, I think it's safe
to say we'd be speaking of the months of Thermidor etc, KmPH at sea,
etc - with charts and computers to match. We'd be dividing circumferential
divisions by factors of 10, rather than by 60 x 6 (to get degrees) and
again by 60 (to get minutes and NMs). Where is it said that 60
enjoys some sort of empirical purity over 10?

>But does it really matter whether some bird is 125 km
>off Westport or ~75 nm (I don't have the conversion at my finger tips)?

Well, 75 nm isn't the right answer (though it's close) so yeah, it might.
Depth of the shelf and all that, which drops dramatically at the edge,
no? The actual distance at which the upwelling along the steep slope
occurs depends on just where you are, of course, but an error of a
couple of miles can run you aground in many parts of the world.

>Most major scientific journals however expect if not require that all
>distances be published in metric form, I think.

Now, here's a curiousity: how are positions recorded in the literature
for pelagic efforts? Probably by lat & long I should think...leaving
the two competing systems out of the equation.

Did the French Navy ever adapt Metric measurements of speed and distance?
Or did they hold to the standard since the Brits of course had the
best charts? I'm curious as I have an interest in history. I mean,
of course, the pre-Trafalgar French fleet.

>I've been a proponent of change for years, but cast common sense to
>the wind; you can't buck the system and a long standing established
>tradition.

I wish the Republicans would accept this view and cede control of the
two Houses of Congress to the Democrats...


- Don Baccus, Portland OR <donb at rational.com>