Mercy! Trying to get my act together, rush around, and stop my current*
tweeters binge* I don't have time to digest and comment on this yet. You are
clearly very scholarly, learned, and/or love playing the devils advocate. If
I can get hooked up from Missouri through the holidays, I'll tackle this one
then. Cheers! --Richard

Richard A. Rowlett <pagodroma at aol.com>
Bellevue, WA USA


On 95-12-22, Don Baccus wrote:

>
>>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>
>
>