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Finally, in this last part, the lame Meter.

It was on the 4^{th} 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 20^{th} 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 20^{th}, so the big day must have been June 23, 1799.

It is by no means only the introduction of arbitrary subdivisions (mere arithmetical adjustment) that removes the “natural” unit of length from nature. No, the Earth itself refuses to sanction the aspirations of the founders of the metric system.

Since the 17^{th }century it has been known that the length of a pendulum beating seconds varies with its location on the Earth; specifically, with the latitude. This is because the constant of proportionality between time and the square root of length depends on the acceleration of gravity *g*—the rate at which the speed of a freely falling body increases—and *g* varies with latitude. Hence if the pendulum is to deliver a unit of length, the arbitrary choice of the second of time must be supplemented by something still less justifiable: the selection of a place on the Earth to put the pendulum.

In this part, “wretched matter” begins to assert itself.

If we want to measure length, we need a unit of length. Given such a unit, not only lengths, but areas and volumes as well, can be expressed in terms of it: foot, square foot, cubic foot. The founders of the new system desired a *natural* unit, one that would not depend upon an arbitrary choice, and that would be perpetually available in the natural world, so that it could readily be consulted in case of doubt. Neither criterion would be satisfied by (for example) the length of the king’s foot.

Milton explained that rhyme was “the Invention of a barbarous Age, to set off wretched matter and lame Meter,” so of course *he* didn’t need it. No more do I need his explanation, only his phrase, to introduce a delightful book, *Les Origines du Système Métrique* (*The Origins of the Metric System*), by Adrien Favre, Professeur au Lycée du Toulouse—which means a high-school teacher in a provincial city, then of a couple of hundred thousand people, far from Paris—published in 1931.

“Before the establishment of our Metric System,” he begins, “there reigned in France, among the units of measure, an incredible confusion.” Naming twenty-two of them, he invites us to think of Rabelais’s lists, and then reveals that the twenty-two were merely the subdivisions of the agrarian measures in one area of the country, Haute-Garonne—a place where, while the measures themselves had only five different names, these designated forty-three different actual measures.