Fourcroy, Charles René De

, marechal de camp, grand cross of the order of St. Louis, director of the royal corps of engineers, member of the council at war and of the naval council, and free associate of the academy of sciences, was born at Paris Jan. 19, 1715. He was the son of Charles de Fourcroy, an eminent counsellor at law, and Elizabeth L’Heritier. Destined to the bar as an hereditary profession, his inclination impelled him into the paths of science, and accident led him into the corps of engineers. An officer of that corps was involved in an important law-suit, which he chose M. de Fourcroy to conduct. M. de Fourcroy directed his son to converse with the officer for the purpose of procuring every information necessary to the success of his cause; but the youth, whose thirst of science was already conspicuous, shewed less attention to the particulars of the lawsuit, than desire to be acquainted with what concerned the service of an engineer; and being informed of the preliminary studies requisite to an admission into that body, he was soon enabled to offer himself for examination.

In 1736 he was admitted into the corps; and was employed under marshal d’Asfeld. His activity, zeal, and knowledge above his years, procured him the confidence of his commander; but, remarking an error in a project which the marshal communicated to him, he informed him | of it For this at first be received thanks; but unluckily he was imprudent enough to entrust this little secret of his vanity to his mother, and her maternal tenderness was equally indiscreet. The marshal had not greatness of mind enough to be indulgent, or ability enough not to be afraid of avowing that he was liable to mistake; and it was long evident that he had not forgiven M. de Fourcroy, both from the commissions which he gave him, and his general regulations, which always tended to prevent his promotion. From this treatment M. de Fpurcroy learnt at an early period to expect nothing but from his services; and he was destined to prove by his example, that virtue is one of the roads to fortune, and perhaps not the least secure.

Engaged in every campaign of the war of 1740, he was charged, though young, with some important commissions and his application during the peace procured him employment in the succeeding war. He made three campaigns in Germany, and in 1761 was commander of the engineers on the coast of Brittany, when the English took BelJcisle. In 1762 be made a campaign in Portugal, where he was present at the siege of Almeyda. Every day M. de Fourcroy worked fourteen hours in his closet, when the duties of the service did not compel him to quit it. An irresistible propensity to the study of natural philosophy would have led him far, had he not been incessantly called from it to the duties of his station. From these he sometimes stole time for making observations; hut, guarding against the illusions of self-love, he communicated most of his researches to men of learning, who have inserted them in their works. The microscopical observations in the “Treatise on the Heart,” which does so much honour to Mr. Senac, are almost all by M. de Fourcroy. Many of his remarks and observations make a part of M. Duhamel’s “Treatise on Fishing,” in which we find the first traces of Spallanzani’s experiments on hybridous fish. IM. de Fourcroy had seen these experiments in a fish-pond in Germany, and gave an account of them to Mr. Duhamel. To him M. Duhamel was indebted also for some experiments with which he has enriched his “Treatise on Forests.” M. de la Lande, too, has acknowledged that he owes him many facts and reflections, of which he has availed himself in his work on Tides. Amongst the essays that M. de Fourcroy published separately, is one in which | he examines how we may judge of the height to which certain birds of passage raise themselves, by knowing that of the point at which they cease to be visible. He published the “Art of Brick-making,” which forms a part of the collection of the academy, to which he also sent several essays that were approved and inserted in their works. The margin of his Collection of the Academy relative to the Arts he has filled with notes, as it was his practice when he read it to examine the calculations, and correct them if they were not accurate.

M. de Fourcroy was employed successively in various parts of the kingdom; principally, indeed, at Calais, at Rousillon, and in Corsica. Everywhere he served with diligence, and everywhere he acquired esteem and veneration. Of this conduct he received the reward in the most flattering manner. M. de St. Germain being appointed minister at war, wished to avail himself in his office of the abilities of some superior officer in the corps of engineers. On this he consulted the directors of that corps, then assembled at Versailles. All with an unanimous voice pointed out M. de Fourcroy, as the most capable of fulfilling the intentions of the minister. M. de St. Germain, who was scarcely acquainted with M. de Fourcroy, wrote to him to come to Perpignan, where he resided. When the minister told this gentleman that he had sent for him without knowing him, to fill a post near himself, and that he was recommended by the officers of his corps, his astonishment may easily be conceived. Of the opinion given of him he shewed himself worthy; and his conduct both public and private, made him honoured and respected.

A life thus busy was rendered more happy by a sentiment, which, born at an early period, expired but with his life. The daughter of M. Le Maistre, the neighbour and friend of his father, and like him famous at the bar, was the companion of his youthful sports, and insensibly chosen by him as the partner of his future days. Whilst M. de Fourcroy was studying under able masters to render himself useful to his country by his talents and acquirements, miss Le Maistre learned from a pious and charitable mother to succour and console the sufferings of her fellowcreatures. The vacations of each year brought together the two young friends, whose minds were so attuned to each other, as if they had never been separated. At that age, when the heart experiences the want of a more lively | sentiment, the tender friendship which united them left them at liherty for no other choice. Both without fortune, they contented themselves with loving each other always, and seeing each other sometimes, till prudence should permit them a closer union. Both sure of themselves, as of the objects of their affection, fourteen years passed without any inquietude but what absence occasioned. After marriage, enjoyment weakened not their passion, as the sacrifice they had made of it to reason had not disturbed their tranquillity. Similar in opinion, their thoughts and their sentiments were common. Separated from the world equally by the simplicity of their tastes, and the purity of their principles, they reciprocally found in the esteem of each other the sole support, the sole reward, of which their virtue had need. Every day they tasted the pleasure of that intimate union of souls, which every day saw renewed. The difference of their characters, which offered the striking contrast of gentleness and inflexibility, served only to show them the power of the sympathy of their hearts. Different from most both in their love and in their virtues, time, which almost always seems to approach us to happiness only to carry us the farther from it afterwards, seemed to have fixed it with them. Perhaps we have not another instance of a passion continuing seventy years, always tender, always the chief (nay the sole, since that they bore for an only daughter constituted a part of it), which lasted uniformly from infancy to old age, not weakened, not once obscured by the least cloud, not once disturbed by the slightest coldness or negligence.

Employed to his last moment in his country’s service, M. de Fourcroy died January 12, 1791, regretted by his family, his friends, and his country. ¹