A Philosophical Dictionary, Volume 05. Voltaire

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СКАЧАТЬ announced by the exterior, is so great a fault that the weak, who abjectly praise it in the great are obliged to soften it, or rather to extol it, by speaking of "this noble fierté." It is not simply vanity, which consists in setting a value upon little things; it is not presumption, which believes itself capable of great ones; it is not disdain, which adds contempt of others to a great opinion of self; but it is intimately allied to all these faults.

      This word is used in romances, poetry, and above all, in operas, to express the severity of female modesty. We meet with vain fierté, vigorous fierté, etc. Poets are, perhaps, more in the right than they imagine. The fierté of a woman is not only rigid modesty and love of duty, but the high value which she sets upon her beauty. The fierté of the pencil is sometimes spoken of to signify free and fearless touches.

      FIGURE

      Every one desirous of instruction should read with attention all the articles in the "Dictionnaire Encyclopédique," under the head "Figure," viz.:

      "Figure of the Earth," by M. d'Alembert – a work both clear and profound, in which we find all that can be known on the subject.

      "Figure of Rhetoric," by César Dumarsais – a piece of instruction which teaches at once to think and to write; and, like many other articles, make us regret that young people in general have not a convenient opportunity of reading things so useful.

      "Human Figure," as relating to painting and sculpture – an excellent lesson given to every artist, by M. Watelet.

      "Figure," in physiology – a very ingenious article, by M. de Caberoles.

      "Figure," in arithmetic and in algebra – by M. Mallet.

      "Figure," in logic, in metaphysics, and in polite literature, by M. le Chevalier de Jaucourt – a man superior to the philosophers of antiquity, inasmuch as he has preferred retirement, real philosophy, and indefatigable labor, to all the advantages that his birth might have procured him, in a country where birth is set above all beside, excepting money.

       Figure or Form of the Earth.

      Plato, Aristotle, Eratosthenes, Posidonius, and all the geometricians of Asia, of Egypt, and of Greece, having acknowledged the sphericity of our globe, how did it happen that we, for so long a time, imagined that the earth was a third longer than it was broad, and thence derived the terms "longitude" and "latitude," which continually bear testimony to our ancient ignorance?

      The reverence due to the "Bible," which teaches us so many truths more necessary and more sublime, was the cause of this, our almost universal error. It had been found, in Psalm ciii, that God had stretched the heavens over the earth like a skin; and as a skin is commonly longer than it is wide, the same was concluded of the earth.

      St. Athanasius expresses himself as warmly against good astronomers as against the partisans of Arius and Eusebius. "Let us," says he, "stop the mouths of those barbarians, who, speaking without proof, dare to assert that the heavens also extend under the earth." The fathers considered the earth as a great ship, surrounded by water, with the prow to the east, and the stern to the west. We still find, in "Cosmos," a work of the fourth century, a sort of geographical chart, in which the earth has this figure.

      Tortato, bishop of Avila, near the close of the fifteenth century, declares in his commentary on Genesis, that the Christian faith is shaken, if the earth is believed to be round. Columbus, Vespucius, and Magellan, not having the fear of excommunication by this learned bishop before their eyes, the earth resumed its rotundity in spite of him.

      Then man went from one extreme to the other, and the earth was regarded as a perfect sphere. But the error of the perfect sphere was the mistake of philosophers, while that of a long, flat earth was the blunder of idiots.

      When once it began to be clearly known that our globe revolves on its own axis every twenty-four hours, it might have been inferred from that alone that its form could not be absolutely round. Not only does the centrifugal zone considerably raise the waters in the region of the equator, by the motion of the diurnal rotation, but they are moreover elevated about twenty-five feet, twice a day, by the tides; the lands about the equator must then be perfectly inundated. But they are not so; therefore the region of the equator is much more elevated, in proportion, than the rest of the earth: then the earth is a spheroid elevated at the equator, and cannot be a perfect sphere. This proof, simple as it is, had escaped the greatest geniuses: because a universal prejudice rarely permits investigation.

      We know that, in 1762, in a voyage to Cayenne, near the line, undertaken by order of Louis XIV., under the auspices of Colbert, the patron of all the arts, Richer, among many other observations, found that the oscillations or vibrations of his timepiece did not continue so frequent as in the latitude of Paris, and that it was absolutely necessary to shorten the pendulum one line and something more than a quarter. Physics and geometry were at that time not nearly so much cultivated as they now are; what man would have believed that an observation so trivial in appearance, a line more or less, could lead to the knowledge of the greatest physical truths? It was first of all discovered that the weight must necessarily be less on the equator than in our latitudes, since weight alone causes the oscillation of a pendulum. Consequently, the weight of bodies being the less the farther they are from the centre of the earth, it was inferred that the region of the equator must be much more elevated than our own – much more remote from the centre; so the earth could not be an exact sphere.

      Many philosophers acted, on the occasion of these discoveries, as all men act when an opinion is to be changed – they disputed on Richer's experiment; they pretended that our pendulums made their vibrations more slowly about the equator only because the metal was lengthened by the heat; but it was seen that the heat of the most burning summer lengthens it but one line in thirty feet; and here was an elongation of a line and a quarter, a line and a half, or even two lines, in an iron rod, only three feet and eight lines long.

      Some years after MM. Varin, Deshayes, Feuillée, and Couplet, repeated the same experiment on the pendulum, near the equator; and it was always found necessary to shorten it, although the heat was very often less on the line than fifteen or twenty degrees from it. This experiment was again confirmed by the academicians whom Louis XV. sent to Peru; and who were obliged, on the mountains about Quito, where it froze, to shorten the second pendulum about two lines.

      About the same time, the academicians who went to measure an arc of the meridian in the north, found that at Pello, within the Polar circle, it was necessary to lengthen the pendulum, in order to have the same oscillations as at Paris: consequently weight is greater at the polar circle than in the latitude of France, as it is greater in our latitude than at the equator. Weight being greater in the north, the north was therefore nearer the centre of the earth than the equator; therefore the earth was flattened at the poles.

      Never did reasoning and experiment so fully concur to establish a truth. The celebrated Huygens, by calculating centrifugal forces, had proved that the consequent diminution of weight on the surface of a sphere was not great enough to explain the phenomena, and that therefore the earth must be a spheroid flattened at the poles. Newton, by the principles of attraction, had found nearly the same relations: only it must be observed, that Huygens believed this force inherent in bodies determining them towards the centre of the globe, to be everywhere the same. He had not yet seen the discoveries of Newton; so that he considered the diminution of weight by the theory of centrifugal forces only. The effect of centrifugal forces diminishes the primitive gravity on the equator. The smaller the circles in which this centrifugal force is exercised become, the more it yields to the force of gravity; thus, at the pole itself the centrifugal force being null, must leave the primitive gravity in full action. But this principle of a gravity always equal, falls to nothing before the discovery made by Newton, that a body transported, for instance, to СКАЧАТЬ