Have you ever wondered why an inch is an inch? According to some sources it started out as a twelfth of a Roman foot. Gee, that helps. In 1150 King David I of Scotland decreed that an inch was the width of a man’s thumbnail at the base. To guarantee some uniformity, it was to be averaged from the thumbnails of a small, medium, and large man. In the 1300s, King Edward II decided to get scientific about it and defined it as three grains of barley, dry and round, placed end-to-end. Later it was twelve poppy seeds. Life must have been hell for carpenters in those days. Since 1959, presumably no further definitions will ever be required because (start Wagner’s "Ride of the Valkyrie" as background music here) metric to the rescue! The inch was officially defined as 2.54 centimeters!
How much is a centimeter? Simple. It’s 1/100 of a meter. Of course, there’s an in-between measure, the decimeter, which isn’t used so much as a measure of length, but a cubic decimeter is a liter, which is a standard measure of volume.
See how nicely it all fits together? Multiply a meter by a thousand and you get a kilometer. Divide it by a thousand and you get a millimeter. By comparison, there are twelve inches in a foot, three feet in a yard, 5,280 feet in a mile. Our scientists have long since been thinking in milligrams and kilograms, centimeters and millimeters, and when the old system inserts itself, the results vary from funny to disastrous. (Don’t ask me for specifics: You know how to use Google!)
The Celsius scale for temperature is also beautifully simple. Water freezes at zero, and boils at one hundred. There’s also the Kelvin scale, which I don’t know much about. It’s based on absolute zero, and it’s only applicable in outer space, in cryogenics, and in Chicago at Michigan Avenue and Wacker Drive in January.
OK, now this means something new to learn, right? I’m used to thinking of a 12-ounce bottle of beer, a hundred-yard football field, how many extra POUNDS of blubber I carry around my middle, and so on. I know my waist size in inches. I know how far it is from my home to the nearest town in miles. At my age, those templates won’t be easy to dislodge. (Although I read and travel enough that I also have wispy metric and Celsius templates to draw on.) Contrary to what a quick learner some of my professors called me, I can be thick headed when it comes to change. As a writer, I fought tooth and nail against converting to an electric typewriter, and later, to a computer, which I now can’t live without. Having learned to drive quite nicely the old stick-shift way, my conversion to automatics nearly caused some major accidents. Only a left knee injury that makes the clutch pedal a torture device took the stick shift out of my life for good.
So it will be an inconvenience to some. But the time is here. There’s so much our kids need to be learning in this day of mushrooming knowledge, let’s not continue to saddle them with an archaic system of measures. We can go on thinking in pounds and miles, we can still say "I won’t give an inch," but before we know it, metric will be natural and easy for all of us, even us old geezers. Most important, it’s one more way in which we can catch up with the rest of the world, for our own good.