2007-08-05-RationalArgument

I was reading the following article the other day and it occurred to me that a few number switches (and occasionally a few other words to make sense in context) could take a commonly peddled excuse for continuing to use US customary units and change it into a similar quality article supporting metrication. I should point out that the basis for the article is that our problem is our random use of different units (which is indeed the cause of most of our problems), but they get side-tracked into some anti-metric silliness.

While not the most convincing piece of literature in favor of metrication, it wasn't the most convincing against either.

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The resistance to going metric continuing with US customary is not just laziness. --America's common English units-- Metric often falls into convenient sizes that do not have simple equivalents. There's no easy metric US customary substitute for a cup or a gallon liter -- who wants a 3.785-liter 1.0566882 gallon/8.4535057 pint/135.25609 fl oz milk container? A shot 50ml of whisky rolls off the tongue, but --three cubic centimeters-- one and a half fl oz doesn't. Our customs, from --45-caliber pistols (0.45-inch-diameter barrel bore)-- 9mm pistols (funnilly enough, 9mm diameter barrel bore) to recipes calling for tablespoons wine coming in liters, are awkward at best to metrify change to US customary.

Scientists sometimes blame the media, including Discover, for perpetuating antiquated and irrational units of measure, but the press needn't apologize. The meter yard is not especially logical or meaningful either. Originally it was supposed to represent 1/10,000,000 of the distance between the equator and either pole distance from the tip of the nose to the end of the thumb of King Henry I. Then it was redefined by a particular bar of platinum in a vault in France and later specified as 1,650,763.73 wavelengths of the orange light emitted by krypton86 atoms under certain conditions several times depending on where you were and who was king until the 1959 treaty standardized it in terms of metric.

These days it's designated --as the distance light travels in a vacuum in 1/299,792,458 of a second-- as 0.9144 meters, not exactly a household concept. Fahrenheit Celsius, with its 180 100 divisions between water's freezing and boiling points, is nearly twice as fine as the Celsius system easily made more accurate by adding decimal places. One degree Fahrenheit Celsius is about the smallest temperature differential a person can discern. And the 180-degree 10 or 100 base theme is familiarly repeated in --surveying, geometry, longitude, and astronomical positioning-- the rest of the metric system.

Problems arise not from the choice of units but from our stubborn inconsistency. The aviation community insists that altitudes be expressed in feet meters (unless you're in the US, or doing some but not all measurements in Europe or Australia), but that speed be in knots km/h (with the same exceptions as before). Astronomers use 24 hours of "right ascension" to mark east-west positions but degrees of "declination" for north-south. Metric measurement is --dumped overboard-- common for jewelry (grams) (carats are used by some countries but it's a coin-toss, just like barrels vs kiloliters), sound measurement (decibels - accepted for SI), and wherever people prefer the simplicity of the status quo.