LEPAUTE-CLOCK AND WATCH-MAKING- 'N the year 1802, died the celebrated watchmaker, Jean Baptiste Lepaute. Let us speak a few words on the subject of this family of illustrious mechanics. Jean André Lepaute, the elder brother of the one just mentioned, was born at Montmedy, in 1709. He repaired to Paris at an early age, where he entered into friendship with the geometrician Clairaut, and Lalande, the astronomer. He executed, in 1753, for the Luxembourg palace, the first horizontal clock ever seen. He invented an escapement which is esteemed one of the best. He presented Louis XV., in 1751, with a watch which had but one wheel. In his treatise on horology, he gives a description of a clock which never required winding up; but this was not a perpetual motion in the strict acceptation of the word. A clock of his is also mentioned, which he called polycameratic, because it struck the hour in the different rooms of a house. Jean André Lepaute was of great service to his art; he was one of the small number of artists who know how to unite to theory the practice of the physical and mathematical sciences. As to Jean Baptiste Lepaute, he was his brother's most assiduous companion and assistant. His most admired production is the fine clock in the Hotel de Ville at Paris, which is considered a masterpiece of art. Another artist, and a competitor of Bréguet, deserves a distinguished place in our gallery. Ferdinand Berthoud has be queathed his talents to his descendants. A Swiss by birth, and destined by his family to the pulpit, his natural tastes showed a strong inclination to clock-making, and induced him to come to Paris to study this art, as well as mechanism in general. Ferdinand Berthoud is the first who firmly established the theory according to which machines for the measurement of time in common use are constructed. His essay upon watch-making, and his treatise upon marine timepieces, are highly valuable to the French nation. His marine timepieces were examined by Borda and other men of science, who proved that they showed the true longitude at sea within a quarter of a degree, or five points at the utmost, after a six weeks' voyage. It may also be remarked, that their regularity was in nowise affected by the firing of cannon. Ferdinand Berthoud, like Bréguet, a member of the Institute, contributed as well as he to the progress of science, both by discoveries and experiments. This illustrious clockmaker educated a pupil worthy of himself: this was Louis Berthoud, who gained a prize at the Institute in 1799, for a chronometer for the decimal division of time. He constructed chronometers whose beauty and accuracy were appreciated by all men of learning; and he obtained, besides the title of marine watchmaker, the privilege of taking pupils, whom he instructed in his art. In after years, his sons proved by the success attendant upon their efforts, as seen at the annual exhibitions, that the family had in nowise degenerated. Nothing contributes so much to the glory of the arts as hereditary talent in families. Of this, we have already cited several examples. The end of the last century presents one, which we must not pass over in silence. Let us go back to the year 1686. In that year was born Julien Leroy, at Tours, who from his earliest infancy betrayed a decided tale for mechanism. At the age of thirteen, he constructed several little clocks. Some years afterwards, he went to Paris to perfect himself in the theory and practice of his art, and soon rose to distinction, his watches rivalling those of the English, heretofore sole masters of the science. Graham, the most celebrated English watchmaker, upon seeing a watch made by Leroy, paid the following honourable tribute to the young man's talents: "I sincerely wish," said he," that I were younger, so that I might make a watch in imitation of this." Voltaire said one day to one of Leroy's sons, "Your father and Marshal Saxe have conquered the English." We must add to Leroy's praises, that he was benevolent; that he sought out the indications of talent in his workmen, assisting them with money; and when satisfied with their labours, it was his custom to pay very high wages. After his death, his son, Pierre Leroy, profiting by his father's instructions and example, was crowned by the Academy for his marine timepieces, which were as remarkable for precision as simplicity. in some degree condensing the flame produced by ordinary combustion, and thereby giving it a brilliancy sufficient for a large apartment, an entry, or a staircase. As M. Charles Dupin observes, Lebon made use in his lamps of the carburetted hydrogen, since employed for lighting streets. After the thermo-lamp, comes the docimastic lamp, or fountain of fire, excellent for soldering metals, glass-blowing, and various mineralogical experiments. The inventor was Bortin. Previously, in oil lamps, the reservoir was placed above the burner, thereby causing an inconvenient shadow. It was very desirable to find a means of obviating this difficulty, as well as of preventing the continually recurring necessity of bringing the oil to a level with the flame. Carcel, whose name, like that of Quinquet, enjoys a universal celebrity, was the first who, towards 1800, constructed a lamp which shed a strong light on all sides without any shadow 11* (125) whatsoever. This was effected by means of internal mechanism. In the Carcel lamp, the reservoir is at the foot, and the oil is raised to the wick by means of a small pump. A wheel-work acted upon by a spring, says the Dictionary of Conversations, and which is wound up like a watch, sets in motion two pumps, which continually raise the oil to the burner. This wheelwork will act eight or ten hours without winding up. There is reason to believe, that if the inventor had lived longer, he would have successively applied the various improvements of which this lamp is capable. It is also probable that he would have reduced its price; for the present Carcel lamp is very expensive. The light of this lamp is very injurious to the eye, from its extreme brilliancy; and a shade of ground glass, or gauze, is generally used, and lately one of porcelain, of a cylindrical or prismatic form, ornamented with figures in relief, presenting very much the appearance of a fine English engraving. The Girard brothers were rivals of Carcel, and arrived at the same result as he, by an ingenious application of the hydrostatic fountain. Whilst these numerous inventions enriched the dominion of industry, the French armies, defending the territories of their republic with heroic energy, opposed victory after victory to the incessant attacks of a formidable coalition. Nevertheless, these regiments of brave soldiers, who went so gayly forward to meet death, were in absolute want of the necessaries of life. A patriotic enthusiasm sustained them under numerous privations. The Marseilles Hymn inspired them with a generous ardour. Glory was sufficient indemnification for all sacrifices. To repulse the enemy was the all-absorbing idea. The youth, become a soldier often against his will, rivalled those who enlisted voluntarily; and, developing his energies on the field of battle, rose rapidly to the rank of general, and learned to command with great skill, uniting the fearless intrepidity of youth to the |