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denominations, more closely than with the exactness of logical analysis.
The nomenclature of the French metrology was established by the law of 7th April, 1795, although the metre and the kilogramme wero only provisional and not definitive. It was known that the difference between the provisional and definitive metre and kilogramme would be very small, scarcely perceptible: and by that inverted logic which presides over all precipitate legislation, it was concluded that because it was small it would be unimportant: instead of which, sound reason would have inferred, that, to the purpose of uniformity, the smaller the difference was, the greater was the danger of its producing confusion between the temporary and the perpetual things which were to bear the same name.
But with the hasty call for a provisional metre and kilogramme, the law of 7th April, 1795, gave the definitive nomenclature, and directed the renewal of all the operations commenced under the direction of the Academy of Sciences; and the persons employed upon them were reinstated in their functions, by the committee of public instruction of the national convention. A commission of twelve persons, Berthollet, Borda, Brisson, Coulomb, Delambre, Haüy, La. grange, Laplace, Mechain, Monge, Prony, and Vandermonde, was appointed on the 17th of April, 1795, for the final accomplishment of the original plan; the most important and laborious part of which, the admeasurement of the art of the meridian, was immediately resumed by Delambre and Mechain. By them the whole distance from Dunkirk to Mont Jouy, near Barcelona, a distance of nine degrees and two thirds, more than a tenth part of the quadrant of the meri. dian, was measured by trigonometrical survey. The angles formed by every station with those next before and after it, rectified by the angles of elevation and depression formed by the inequalities on the surface of the ground, to reduce the whole to the level of the horizon, were measured and referred to the measure of two bases, one between Melun and Lieusaint, the other between Vernet and Salces, near Perpignan; each serving as a corrective upon the other. Observations of azimuth ascertained the direction of the sides of the triangles, with reference to the meridian; and astronomical observations ago certained the celestial arc, corresponding with that which was measured upon the earth. The distance from Dunkirk to Rhodez, about 450 miles, was performed by Delambre; and that from Barcelona to Rhodez, upwards of 200 miles, by Mechain. The base of Melun was of 6075.90 and that of Perpignan 6006.25 toises, each nearly seven miles : and though at the distance of near 400 miles from each other, the base of Perpignan, calculated by inference from the chain of triangles between them, differed from its actual admeasurement less than one foot. The portion of the distance allotted to Mechain was less than one third of the whole; but, traversing the Pyrenees, and being chiefly upon the Spanish territories, was attended with more difficulties than those encountered by his associate. Mechain, in the execution of his task, bad formed the project of extending the survey
to the Balearic islands, which would have made the portion of the arc south of the forty-fifth degree equal to that northward of it. With a firmness and perseverance of pursuit, amidst innumerable obstacles, he had proceeded far in the execution of this supplementary plan. His triangles were already extended from Barcelona to Tortosa. His stations had been selected to Cullora. Six or seven triangles more would have carried his work to its termination in the island of Ivica. Arrested by a fever, in his first progress, and compelled then to abandon the attempt, he had resumed it after the result of the original plan had been ascertained, and the new system had been finally established by law. The band which sets bounds to all human pursuits again and definitively met and closed his career. He died on the 20th of September, 1805, at Castellon de la Plana, in the Spanish province of Valencia. His more fortunate associate, Delambre, has published, in three quarto volumes, under the title of the “ Basis of the metrical decimal system, or measure of the arc of " the meridian between Dunkirk and Barcelona,” all the details and results of this admirable operation. A fourth volume yet remains to be published, which will contain the account of the actual execution since the death of Mechain, of the idea which he had conceived of extending the admeasurement to the island of Formentara, and of the additional extension of it northward to the Shetland islands, by connecting it with the trigonometrical survey of Great Britain. This work, in passing to future ages, a monument of the philosophy, science, public spirit, and active benevolence of our own, will redeem, by the martyrdom of genius and learning in the cause of human happiness, the blood-polluted glories of cotemporaneous war.
The reports of the proceedings of Delambre and Mechain, as well of their field surveys as of their astronomical observations, and all their calculations, were submitted to the inspection, scrutiny, and revision, of a committee of the mathematical and physical class of the national institute, that phenix of science which had arisen from the ashes of the academy of sciences. The observations to ascertain the length of the pendulum, and the experiments for determining the specific gravity of distilled water at its maximum of density, were submitted to the same ordeal. Two reports upon the whole result were made to the class, one by Trallés of the Helvetic Confederation, the other by Van Swinden of the Netherlands, two of the foreign associates, who had been invited to co-operate in the labor, and to participate in the honor of the undertaking. These two reports, combined by Van Swinden into one, were then reported from the class to the general meeting of the institute, and by that body, with all suitable solemnity, to the two branches of the national assembly of France, on the 22d of June, 1799, together with a definitive metre of plativa, made by Lenoir, and a kilogramme of the same metal, made by Fortin. They were introduced by an appropriate address at the bar of the two houses, by the presiding member of the national insti. tute, La Place; to which answers were returned by the respective presidents of the two legislative chambers. On the same day, the
standard metre and kilogramme were deposited in the hands of the keeper of the public archives; and a record of the fact was made and signed by him, and by all the members of the institute, foreign associates, and artists, whose joint labors had contributed to the consummation of this more than national undertaking.
No apology will be deemed necessary by Congress for dwelling upon these details which signalized the establishment of the new French metrical system. The spectacle is at once so rare and so sublime, in which the genius, the science, the skill, and the power of great confederated nations are seen joining hand in hand in the true spirit of fraternal equality, arriving in concert at one destined stage of improvement in the condition of human kind; that, not to pause for a moment, were it even from occupations not essentially connected with it, to enjoy the contemplation of a scene so honorable to the character and capacities of our species, would argue a want of sensibility to appreciate its worth. This scene formed an epocha in the history of man. It was an example and an admonition to the legislators of every nation, and of all after-times.
On the 10th of December, 1799, (19 Frimaire 8, the temporary metre and kilogramme, which had been ordained by the laws of 1st August, 1793, and 7th April, 1795 (18 Germinal 3,) were abolished. That metre bad been of 443 lines and 47 of a line of the ancient foot, standarded by the fathom of Peru. The new and definitive metre was fixed at 443 lines 1767. The difference between them was about
of a line, or to of our inch, a difference imperceptible for all ordinary uses; but very important as a standard variety, and immediately apparent when multiplied to the cube for the measure of capacity and the weight. Thus the temporary kilogramme had been of 18,841 grains mark weight, while the new and definitive kilogramme was reduced to 18,827.15 grains.
During the violent ebullitions of the most inflammatory period of the French Revolution, it had been imagined that in the reformation of the system of weights and measures, upon the principle of uniformity, the mensuration of time ought to be included. But this was a different project from that of the reformed metrology, originating in motives less pure and ingenuous, connected with purposes interfering with religious impressions, and quite inconsistent with one of the principal expedients of perpetuating the identity of the new weights and measures. The length of the pendulum beating seconds, it has been seen, is, in the new metrical system, the test of verification for that of the metre, in case the original platina standard should be Jost. The pendulam beating seconds vibrates 86,400 times in the solar day of 24 hours. But, the fiery spirits of the Revolution called for a reformation of the calendar, for a new constitution of the sea. sons, and above all, for decimal divisions. The establishment of the French republic was a new æra to the world. It had taken place on the 22d of September, 1792, the day of the autumnal equinox, when the sun entered the sign of the Balance, the symbol of equality. Before it the Christian æra was to disappear. The new year was to
commence with that day. The division of twelve months was to be retained; but they were all to be of three times ten or thirty days. The division of weeks of seven days, beginning with one specially devoted to the worship of the Creator, and repose, was to be abolished; but every tenth day was to be dedicated to some moral abstraction or virtue, such as liberty, equality, fraternity, patriotism, conjugal affection, filial piety, old age, and once a year to the Supreme Creator, whose existence was formally authenticated by a decree of the national convention. After their thirty-six decads, there remained five, and in leap-year six complementary days, to which they gave a name which can scarcely be repeated with decency; but which were to be all holidays, and in which were to be revived the Olympic games of ancient Greece. The names of the months were to be significant. The three successive months, composing each of the four seasons, were to have the same terminating syllable, which in its sound should convey to the ear its distinctive character. The first of the four was aire, which was supposed to indicate the solemn and majestic tranquillity of autumn; the second ose, a dull and heavy sound, marking the torpor and frigidity of winter; the third al, which bad all the reviving influence and liquid barmony of spring; and the fourth dor, burning to the fancy with the vivid ardors of summer. To these terminating syllables, each month had an appropriate prefix. Thus, in autumn, Vendemi-aire, was the month of vintage ; Brum-aire, the month of fogs; and Frim-aire, the month of incipient cold. From the winter solstice to the vernal equinox, there was Niv-ose, the month of snow; Pluvi-ose, the month of rain ; and Vent-ose, the month of wind. These were succeeded by the darlings of the year; Germin-al, the month of buds; Flore-al, the month of blossoms; and Prairi-al, the month of blooming meads. The procession closed with the bounties and fervors of summer; Messi-dor, the month of harvests; Thermi-dor, the month of heat; and Fructidor, the month of fruit. The days of their decad were to be denominated by their numbers from one to ten; as Primedi, first day, Duodi, second day, and so on to Decadi, the tenth day; which was to be the day of relaxation from labor, and of meditations upon virtue. But the clashing of the new calendar with the new metrology was the division of the solar day, not into 24 hours, of 60 minutes, with 60 seconds to the minute ; but into ten hours, each of 100 minutes, and each minute of 100 seconds. The pendulum of that day, therefore, would vibrate 100,000 times, and would be of quite a different length from that which was to be the test of verification to the metre.
This system has passed away, and is forgotten. This incongruous composition of profound learning and superficial frivolity, of irreligion and morality, of delicate imagination and coarse vulgarity, is dissolved. This statue, with the form of Apollo and the face of Silenus, has crumbled into dust; but it was established by a law of the 5th of October, 1792, and for the space of twelve years it was the calendar of the French nation. Henceforth it will only be remembered as preparing future problems in chronology.
The division of the day into a hundred thousand parts had some reasons to recommend it, but was the first part of the system that was abandoned. It had been decreed as compulsory, with the new nomenclature of the calendar, on the 24th of November, 1793, (4 Frimaire 2,) but this regulation was indefinitely suspended by the law of 7th April, 1795, (18 Germinal 3.)
On the 8th of April, 1802, when a First Consul, soon to be for life, had produced some perturbation of that balance, the symbol of equality in which the sun had first shone upon the French Republic, there passed a law, retaining the equinoctial or republican calendar for all civil purposes, but resuming the solstitial or Gregorian calendar so far as to restore its week of seven days with their names, and its Sabbath of the first of them. The terms equinoctial and solstitial, in this law, applied to the new and old calendars, seem studiously selected to veil the balance of equality on one side, and the Sabbath of religion on the other.
But on the 9th of September, 1805, (22 Fructidor 13,) in the month of fruits, and when the sun of the French Republic had got, if not into the sign, at least deep into the constellation, of the Lion; when the legend of her coins bore on one side the name and head of Napoleon Emperor, and on the other, the name of the French Republic, a senatus consultum ordained, that, from the 11th of that dull and heavy month of snows of the 14th year, the 1st of January, 1806, should re-appear, and the Gregorian calendar should be restored to use throughout the Republican Empire.
The decimal divisions, and the fanciful contexture of the equinoc tial calendar, were a sort of episode to the new system of metrology. The attempt to decimate the year in its number of days was equally useless and absurd. The five successive holidays at the close of the year, just at the season of the vintage, with the institution of athletic sports, were a waste of time, and a provocation to mischievous idleness, ill compensated by the retrenchment of sixteen Sundays in the year, at the distance of a week from each other, and devoted to the exercises of piety.
The application of the metrical system to geography and astronomy was a much more rational part of the project; but has been attended with difficulties in execution hitherto insuperable. In adopt.. ing an aliquot decimal part of the quadrant of the meridian for the unit of long measures, it formed a natural division of the quadrant itself into ten parts, each of ten degrees. The degree would then have been of 100,000 metres, and the number of degrees to encircle the earth would have been four hundred. The degree, which is now of about sixty-nine English miles, would have been of about sixtytwo, and the facility of all astronomical, geographical, and nautical, calculations, would have been much increased. But it would have rendered useless all the tables indispensable to the navigator, astronomer, and geographer; and, if it bad not produced the same effect