ARCON, J. C. E. Le Michaud d’, a French engineer and military writer of eminence, and memorable as the inventor of the floating batteries employed against Gibraltar, was born at Pontarlier in the year 1733. He was originally destined for the church; ‘but, instead of em-plying himself in the studies suited to that profession, he became wholly engrossed with plans of fortifications, and was at length admitted, with the consent of his parents, into the corps of engineers. He distinguished himself at several sieges during the seven years’ war; and had acquired so much reputation by his professional services and by his writings, that he was specially employed to assist in the last grand effort made by France and Spain for the reduction of Gibraltar in 1782. It was about this period that he projected the famous floating batteries; an invention which inspired the combined armies with the greatest hopes of success, and which at first occasioned no small degree of alarm in the British garrison. “The battering ships,” says Drinkwater, in his interesting account of this memorable siege, “were ’ found to be no less formidable than they had been represented. Our heaviest shells often rebounded from their tops, whilst the 32 pound shot seemed incapable of making any visible impression upon their hulls. Frequently we flattered ourselves they were on fire; but no sooner did the smoke appear than, with the most persevering intrepidity, men were observed applying wa ter, from their engines within, to those places whence the smoke issued.” Of the ultimate fate of these expensive and formidable engines of attack all British readers must be sufficiently informed. Not one of the whole ten escaped destruction from the bombs and red-hot balls poured upon them from the garrison. Μ. d’Arçon, however, published a memoir to show that his batteries were wilfully exposed to destruction through the envy and jealousy which the contrivance had excited among the Spaniards; and this statement seems to have obtained the general concurrence of his countrymen. But projectors do not readily admit umy inadequacy in their schemes; nor will a vain-glorious people, who have been foiled in war, ever ascribe their disgrace to the superior skill or constancy of their enemy.

Μ. d’Arçon appeared in the capacity of a general in the first years of the Revolution; and, in particular, was employed in the invasion of Holland, where, in 1793, he besieged and took several fortified places. He soon afterwards withdrew or was driven from public life, and remained in retirement till 1799, when he was made a member of the Conservative Senate by Buonaparte. He died the following year, aged sixty-seven. He was a member of the Institute, and author of the following works :—1, Reflexions d’un Ingénieur, en réponse à un Tacticien, 1773, 12mo; 2, Correspondance sur l’Art de la Guerre, entre un Colonel de Dragons et un Capitaine d’Infanteric, 1774, 8vo; 3, Défense d’un Système de Guerre Nationale, &c. 1779, 8vo; 4, Mémoires pour servir à l’Histoire du Siège de Gibraltar, 1783, 8vo; 5, Considérations sur l’influence du Génie de Vauban dans la Balance des Forces de l’Etat, 1786, 8vo; 6, Examen détaillé de l’importante Question de l’Utilitédes Places Fortes et Retranchements, 1789, 8vo; 7, De la Force Militaire Considérée dans ses Rapports Conservateurs, 1790, 8vo; 8, Considérations Militaires et Politiques sur les Fortifications, 1795, 8vo. This work was published at the expense of the government, and contains a sort of digest of all his observations and opinions on military subjects.—See Biographie Moderne, tome i., and Biographie Universelle, tome ii.