Finally, in this last part, the lame Meter.
It was on the 4th of Messidor in the year VII that the standard meter, and with it the standard kilogram, were presented to the legislature. —What, Messidor? VII? Yes, the Republic had been inaugurated on September 22, 1792, and on that day (it was eventually decided) began Year I. Years of the Republic had twelve months of 30 days each, plus some festival days; and the months, each beginning around the 20th of an English month, were Vendémiaire (Vintage-y), Brumaire (Misty), Frimaire (Frosty), Nivôse (Snowy), Pluviôse (Rainy), Ventôse (Windy), Germinal (Bud-y), Floréal (Flowery), Prairial (Meadowy), Messidor (Harvest-giver), Thermidor (Heat-giver), Fructidor (Fruit-giver). These names, bestowed by Fabre d’Églantine, whose head was cut off for his pains, were probably thought more dignified and poetical than those contrived by Sir Gregory Gander for the English calendar:
Showery, Flowery, Bowery,
Hoppy, Croppy, Droppy,
Breezy, Sneezy, Freezy.
But they were hardly more exact. Besides, Sir Gregory kept his head. —Messidor began on June 20th, so the big day must have been June 23, 1799.
As we know, the length of the meter has no genuine basis in nature. It is obtained by a decimal division of the quadrant of a meridian, an arbitrary, indeterminate quantity inexactly measured; and of what use is it that the meter stands, approximately, in a simple relation to the circuit of the Earth? “This unit,” it was seriously affirmed on Messidor 4th “at the bar of the Councils” (whatever they were), “offers an aspect not without interest. There is a certain pleasure, for a father of a family (un père de famille), in being able to say to himself: the field which sustains my children is such-and-such a portion of the globe. I am, in this proportion, co-proprietor of the world.” This powerful reasoning, Favre opines, is an instance of a more general consideration: “The idea, ‘flattering to human pride’ [as Jacobi called it later], of relating the system’s everyday measures to the dimensions of the Earth, doubtless contributed to facilitating its propagation abroad. The fiction that served as basis of the system had no other purpose. The ‘natural’ basis had been chosen, one could say, for export.”
If for a moment we can put away our pride, we see at once that the choice of the meter was ill-considered. It’s too long! The English yard (similar in length) has its uses, but the foot is much more popular, and there’s a reason for that: it fits ordinary human affairs. So does the inch. We’re a few feet tall, a foot or two broad; our hands are a few inches long, a few inches across; and we tend to deal with things our size. Sensible Thomas Jefferson, who (you recall) favored the length of the pendulum as the source of measure, proposed taking three tenths of it as the basic unit—that is, a trifle less than a foot. Would his three-tenths have confounded the co-proprietorship of the père de famille, affronted human pride, and suppressed the export of French measure? One may doubt it. Had the savants had the common sense to choose a “meter” about a foot long, a tenth of it would have served well in place of the old inch, and we would not have been stuck with the present centimeter, which is too short for ordinary purposes (not to mention the decimeter [10 cm], which is too long, and indeed never is mentioned). As it is, ask a Frenchman how tall he is: 1.78 meters, he will say, for example; ruefully, we may assume. Would not Jefferson’s meter have produced a better answer? The one we have deserves Milton’s censure, for it is truly lame.
Of course, there is the additional matter (no light one) of a unit of weight, every bit as important as the unit of length—nay, probably more important, for commerce at least. Now as Favre says, “there is no necessary relation between the unit of length and that of weight,” but a way from the former to the latter readily suggests itself: unit length determines unit volume, and the unit volume of a specified substance will have unit weight. Which substance?—gold? mercury? Rather, water, everywhere available and easily purified. Its temperature must be specified, to fix its density; this was finally chosen as the temperature at which the density is greatest, about 4º C. —I have been speaking of weight, but in fact the universal unit must be of mass, the quantitative aspect of matter which jointly with the acceleration of gravity g determines weight; for since g varies with location on the Earth (see Part III), so does the weight of a given volume of water, whereas the mass of that water, dependent only on the quantity of matter present, is determined by the volume alone.
So you would expect the unit of mass to be the mass of a cubic meter of water. But that’s heavy, weighing more than a ton, so a millionth of it was chosen to have the unit name: a gram is the mass of a cubic centimeter of water. But that’s light, 1/28 ounce, so a thousand times it was taken as a standard to be manufactured and presented along with the meter stick—the kilogram, awkwardly enough, not the gram, accompanies the meter.
It is convenient that a kilogram of water occupies not much more than a quart (a liter), thus approximately preserving one customary measure. But if the meter had been a foot long, we would have done just as well. As Cotes, and Lavoisier, and Jefferson observed, a cubic foot of water weighs just about 1000 ounces (Jefferson imagined the relation to hold “with mathematical exactness”); thus a cubic tenth-of-a-foot weighs an ounce. One, and ten, grams are quantities too small for measuring food, while 100 grams of water is less than half a cup, too big and too small at once; an ounce, and ten ounces, are good sizes, and 100 ounces of water is 3 1/8 quarts, not far from a gallon.
The units, then, were ill-considered; and no surprise: “The founders of the Metric System hesitated much less over the choice of the units than over the names to give them”! I won’t go into this amusing story, except for a little on Greek prefixes. A “deputy of the tribune of Five Hundred” (don’t know what that was either) lamented, “‘You have to learn Greek to know that hecto signifies hundred and kilo thousand.’ People who had learned Greek remarked that hectos signifies a sixth and not hundred, and they found fault precisely with the form of these prefixes as being not Greek, but ‘barbarous.’” A hundred mètres should be called hécatommètre, not hectomètre, they sniffed. But it was explained that “the savants will know that hecto is here an abbreviation of hécaton. The others will hardly care.”
Despite all this, the meter, the kilogram, and their relatives have one inestimable virtue, briefly stated by Favre: “The real superiority of the Metric System consists in the decimal division. By that, calculations are greatly simplified.” I need not argue for this evident truth, even though decimals proved an obstacle to acceptance of the system, since ordinary folk (those already overlooked when choosing the length of the meter) naturally divide by 2 and 3, not 10—nor have they stopped doing so. How much better it would be if our number system were based on 12 instead of 10! Thirds, and halves of halves, and halves of thirds, would be taken as easily as halves. This modification was proposed, but was judged too revolutionary even for France… Anyway, so valuable was decimal division thought to be, that enthusiasts sought to install it all around them. You can’t do anything about the number of days in a year, but you can have a ten-day week, and they did: the décade! The thermometer was revised! A decimal day was proposed! Students at the short-lived École de Mars (Mars School) received a revolutionary education in their tens, hundreds, and thousands! “Thus,” writes Favre, “the decimal division became the object of a veritable superstition. It was put in everywhere, like the nutmeg in the Festin Ridicule (Ridiculous Banquet).”
Our author’s allusion gives me the opportunity to conclude here as I began Part I, with a poet who has nothing to do with my subject. Boileau, a generation younger than Milton, wrote satires, among other things, and a funny one is the third, found here. Its narrator cannot evade a fop, who “in order to poison me,” forces him to accept an invitation to dine. At the banquet everything that can go wrong does; but the host, well pleased with his table, encourages his guest with the alexandrine, Aimez-vous la muscade? on en a mis partout (“Do you like nutmeg? it’s been put in everywhere”). If my reader, expecting literature, has found objectionable the measures put everywhere into this series of posts, let him or her requite me with a satire as effective as Boileau’s.