Élie De Beaumont, Jean-Baptistearmand-Louis-L

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Élie De Beaumont, Jean-Baptistearmand-Louis-Léonce

(b. Canon, Calvados, France, 25 September 1798; d. Canon, 21 September 1874)

geology.

Élie de Beaumont was the elder son of Armand-Jean-Baptiste-Anne-Robert Élie de Beaumont and Marie-Charlotte-Eléonore Mercier Dupaty; their marriage united the families of two jurists who had achieved fame under the ancien régime.

Following a widespread custom of the bourgeoisie in the eighteenth century. Élie de Beaumont’s grandfather, Jean-Baptiste, a Norman lawyer, joined to his patronymic the name of an estate, in order to distinguish himself from his brother Jean-Antoine, docteur régent of the Faculté de Médecine of Paris.

Under the Empire, Léonce’s parents, who were living at Canon, engaged a Benedictine monk, Dom Raphaël de Herino, to serve as tutor to him and his brother, Charles-Adolphe-Eugéne. At the beginning of the Restoration, when the children had nearly completed their secondary studies, the family moved to the rue de la Muette, in Faubourg Saint-Antoine, a quarter of Paris not far from the Collége Royal Charlemagne. At this collège, where he was called Élie-Debeaumont, Léonce obtained fourth honorable mention in elementary mathematics in the general competition of 1816. In 1817, after a year of higher mathematics at the Collége Henri IV, he won first prize in mathematics and physics in the general competition and was second on the admissions list of the École Polytechnique, which methodically collected the country’s most gifted students for intensive training in mathematics. Graduated first in his class from the Polytechnique, he chose the Corps des Mines, which had not received any engineering student from the last three graduating classes. He entered the Ecole Royale des Mines on 15 November 1819.

The École des Mines offered four two-year courses. Baillet du Belloy, in his course on the working of mines, also discussed hydraulic engines, steam engines, and subterranean topography; Berthier taught docimasy (analytic mineral chemistry); Hassenfratz described the primary treatment process for all kinds of ores (that is, ore dressing, or beneficiation of ore); and Brochant de Villiers alternately taught one year of mineralogy and one of geology. Between the first and second years the engineering students worked in the laboratory, practiced drafting, and made plans of the catacombs. After the second year they undertook study trips of several months’ duration in a mining or metallurgical region, following an itinerary outlined in detail by the council of the École des Mines. Their studies were judged complete when they had attained a certain level in each subject area. In general, students had to spend a third year at the École des Mines in order to reach that level and then were required to take a second study trip.

This was the case with Élie de Beaumont, who, beginning in November 1820, also attended the Faculté des Sciences in Paris. During the summer of 1821 he devoted his first study trip to visiting the iron mines and forges in eastern France and began making geological observations in the Vosges, where his guide was Philippe Voltz, a mining engineer in Strasbourg who was particularly interested in paleontology. In 1822 a second study trip took Élie de Beaumont to Switzerland, where his guide was Jean de Charpentier, director of the salt mines of Bex and a former student of Werner’s at the Freiberg Bergakademie. Charpentier also acquainted Élie de Beaumont with his observations on glaciers: he was the first to propose that they had transported erratic boulders deposited on the Swiss Jura. Élie de Beaumont returned on foot to Paris, passing through Auvergne. The main portions of his journals of the two trips, which were considered useful in teaching others, were published in the Annales des mines in 1822 and 1824.

On 1 January 1823 Élie de Beaumont was named an engineering cadet at the same time as Charles Combes, who had been in the class after his. All the mining engineers, including the older ones like Hassenfratz and Héron de Villefosse, were concerned about France’s underdeveloped industry, especially vis-à-vis England. They thought that first priority should be given to putting France on an equal footing with its rival, especially in the use of steam engines, the development of collieries and mines, and in metallurgy. At the Ministry of the Interior their point of view was shared by the director general of bridges, highways, and mines, Louis Becquey.

The absence of outcroppings and the lack of knowledge of the substrata made prospecting for sedimentary deposits, particularly the search for coal beds, extremely uncertain. To all those concerned with the development of a mineral industry in France, the importance of preparing a geological map had become evident. The idea of representing the nature of the terrain on a topographical map was not new in France. In 1664 the monograph of the Abbé Louis Coulon, Les rivières de France, ou Description géographique et historique du cours et débordement des fleuves, rivières... de France, avec un dénombrement des villes, ponts, passages,..., had been reprinted, accompanied by a map indicating the boundaries of the granite and the sedimentary formations.

In the middle of the eighteenth century, when Guettard had surveyed northern France, he had perceived that the different formations that constitute its soil form large concentric bands about Paris. In 1746 he published in the Mémoires de l’s Académie royale des sciences a map in which he proposed “to show that there is a certain regularity in the distribution of the rocks, the metals, and most of the fossil substances.” Subsequently he was commissioned by Bertin to explore the whole of France from the point of view of mineralogy and to publish descriptions and maps of the provinces.

Originally it had been planned to cover all of France by means of 214 mineralogical maps, but a lack of funds permitted only forty-five maps to be made. Monnet published them in 1780 in the Atlas et description minéralogiques de la France, entrepris par ordre du Roi... lre partie, comprenant le Beauvoisis, la Picardie, le Boulonnais, la Flandre Française, le pays, Messin, et une partie de la Champagne.

On 6 July 1794 the Committee of Publish Safety issued a decree (the text of which Hassenfratz had composed) that the engineers of the Corps des Mines were to search for mineral substances in their districts and to map their discoveries. The Journal des mines published several geological memoirs written by mining engineers, as well as mineralogical reports on several departments by Coquebert de Montbret. In collaboration with the latter, the geologist Omalius d’Halloy prepared, between 1810 and 1813, “Essai d’une carte géologique de la France, des Pays-Bas et de quelques contrées voisines.” It was published in the Annales des mines, but not until 1822, when the subject had become of current interest. This map, drawn on a scale of about 1:3,600,000, distinguished six great rock systems: primordial, penean, ammonean, cretaceous, mastozooic, and pyroidic.

Brochant de Villiers, commissioned in 1802 to teach geology at the École des Mines, had seen the importance of preparing a more detailed geological map. In 1811 he had presented to the director-general of mines, Count Laumond, a project for the execution of such a map. But Napoleon and his ministers, who did not understand the revolutionary economic role of the steam engine and were thus unable to grasp the importance of developing the coal industry, considered the establishment of a geological map to be one of those academic exercises that can be postponed indefinitely.

The Corps des Mines had to wait for the fall of the Empire to triumph over Napoleonic obtuseness. The royal order of 5 December 1816 instructed the council of the École des Mines, reestablished in Paris at the Hôtel Vendôme, to assemble all the materials necessary to complete the mineralogical description of France, and subsequently commissioned it to amass mineral collections and to publish geological and mining maps.

In 1820 the English geologist George Bellas Greenough published a geological map of England in six sheets, a copy of which he sent to the directorgeneral of bridges, highways, and mines. On 11 June 1822 the council of the École des Mines, judging the occasion favorable, repeated its intention to produce a geological map of France and invited Brochant de Villiers to present a new report on this subject to Becquey. On 15 June, Brochant proposed that a mission composed of himself and two young mining engineers go the following year to England in order to confer with and study the methods of the English geologists. Dufrénoy, prompted to mining engineer on 1 June 1821, was the first collaborator that Brochant thought of, and Élie de Beaumont’s good fortune was to complete his studies at the moment when a second assistant was being sought.

On 25 April 1823 Élie de Beaumont was invited by Becquey to leave immediately for Dover, “in order to improve his knowledge of the English language by speaking with Englishmen,” and to wait there for Brochant and Dufrénoy. Their mission lasted six months. They inspected, in particular, tin and copper mines in Cornwall, lead mines in Cumberland and Derbyshire, and coal mines and ironworks in Wales. Upon their return Becquey complimented them for their work and for the smallness of their expenses. Dufrénoy and Élie de Beaumont devoted 1824 to composing memoirs on their mission, which were published in the Annales des mines.

Élie de Beaumont, appointed as mining engineer in May 1824, was assigned on 1 September 1824 to the Service des Mines at Rouen and placed in charge of the Seine-Inférieure (now Maritime) and Eure departments. On 29 June 1825 Becquey wrote to Brochant:

I have reread your report of 15 June 1822 and the opinion of the council of the École des Mines. All these documents have strengthened me in the resolution that I announced to you in 1820: having a geological map of France made. This work is important: its results should be eminently useful and its execution can only bring honor to the Royal Corps of Mining Engineers. Consequently I approve the various measures that you proposed to me in concert with the council of the École des Mines. The mineralogical description of France ought therefore to include all the information relative to the nature of the terrain that could be of interest at once to geology, the art of mining, and all the other arts practiced on mineral substances, as well as information on the different kinds of formations, their relationships, their boundaries, exploited and unexploited deposits of useful minerals, and finally, the location of mine mills, In order to present without confusion such manifold and very often closely related data, one should draw up: (1) a general geological map of France including all information on the nature of the formations; (2) departmental geological and mineralogical maps. The work will commence with the general geological map.... Your proposed geological division of the work among the engineers seems to me clear and precise. I easily follow the twisting diagonal line by which you divide France, which goes from the northwest to the southeast, running along the boundary of the great chalk massif from Calvados to the vicinity of Saumur, Châtellerault, and Auxerre, then turning back toward Avallon and Chalon and, beyond that, following the course of the Saône and the Rhone.... Each year please inform me in advance of the probable expense, since funds are so limited that I must be sure of being able to meet expenses before authorizing them. According to the information that you have presented, the total expense for 1825 will be approximately 3,000 francs, including everything.

Dufrénoy in charge of the western division, and Élie de Beaumont, in charge of the eastern division, spent the first five years, from 1825 to 1829, exploring their sectors on foot during the summer months, nothing their observations on Cassini de Thury’s map, drawn up on 180 sheets on a scale of 1 line for 100 toises (1:86,400). From 1826 to 1828 Dufrénoy was assisted by E. de Billy, and Élie de Beaumont by Fénéon. In 1830 they went to the Alps with Brochant to verify the abnormal contact, observed by Élie de Beaumont, of granite and an underlying calcareous layer; this inaugurated their joint expeditions, which were continued until 1836. On 20 December 1841, they presented to the Académie des Sciences the Carte géologique générale de la France, drawn on six sheets on a scale of 1:500,000, and the first volume of the Explication. The 100-page introduction to the latter is still the best that can be placed at the beginning of modern treatises on physical geography.

Dufrénoy and Élie de Beaumont, appointed mining engineers first class in May 1832, henceforth received the same promotions at the same time: chief engineer in May 1833 and inspector general in March 1848.

From 1825 Élie de Beaumont devoted himself almost exclusively to geology, on which he started to lecture in 1827 at the École des Mines and in 1832 at the Collège de France, where in 1848 he had as auditors the students of the first École d’Administration.

On 22 June 1829 Élie de Beaumont presented to the Académie des Sciences his first ideas on tectonics, showing that the various mountain chains are of different ages. In this exposition, to which Arago devoted seventeen enthusiastic pages in the Annuaire pour 1830 of the Bureau des Longitudes, Élie de Beaumont distinguished six systems of uplift, each characterized by one direction. In 1833, in a note inserted in the translation of Henry De la Beche’s Manual of Geology, he increased the number systems to twelve. In 1834, at the Sociéte Géologique de France, of which he had been one of the founders in March 1830, his hypotheses were sharply criticized by Ami Boué.

In 1833, in a memoir entitled Sur les groupes du Cantal, du Mont-Dore et sur les soulèvements auxquels ces montagnes doivent leur relief actuel, Dufrénoy and Élie de Beaumont unfortunately borrowed from Leopold von Buch the theory of elevation craters. They thought that great lava flows can spread only over surfaces that are almost horizontal. Occasionally a force acting upward from below, which they supposed was the upward from below, which they supposed was the upheaval of a plug of solid lava, would raise the flows thus formed and build what they called an elevation cone. At the point of application of this force, they sated, a crack with divergent fissures was produced; this divided into triangular sectors the fragments of lava that henceforth constituted the sides of the cone. When flows or thrusts produce a gap at the summit, this constitutes an elevation crater. Since there are spaces between the lava sectors thus formed, Dufrénoy and Élie de Beaumont developed formulas for the calculation of their area as a function of the diameter of the base of the cone and the slope of its sides. After stating these formulas, they believed, contrary to the evidence, that they were verified by observation in central France and then at Vesuvius and Etna, which they inspected the following year with Buch.

In 1846–1847 Éile de Beaumont devoted his course at the Collège de France to volcanic and metalliferous emandations; he continued it on 5 July 1847 at the Société Géologique de France in a statement that was the first complete theory of metalliferous veins. It is his most solid scientific work besides his surveys for the geological map.

On 5 May 1838, at the Société Philomathique, Élie de Beaumont appeared like a mathematician lost among the natural sciences, applying to sedimentary folds considerations borrowed from the theory of ruled surfaces; and these considerations, moreover, were not original, since, as Babinet observed, they had already been stated by Monge in another form.

A growing detachment from observation and a love of calculation led Élie de Beaumont, beginning in 1850, to connect the stylized directions of the mountain chains to a system of terrestrial great circles forming regular pentagons in gnomonic projection. This was the point of departure for his delusory theory of the pentagonal grid, which he represented in 1866 on the Carte géologique générale de la France and which was taught for some thirty years at the École des Mines.

On 21 December 1835 Élie de Beaumont was elected to the Académie des Sciénces, in the mineralogy section; on 19 December 1853 he was named perpetual secretary for the mathematical sciences, replacing Arago. In December 1859 he married Thérèse–Marie–Augusta de Quélen, the widow of the marquis du Bouchet; she died childless in 1866.

Élie de Beaumont was director of the Service de la Carte Géologique from its organization in 1865 until 1868, when, having reached the age of retirement, he had to cede to Combes the chairmanship of the Conseil Général des Mines, an office which he had held since 1861.

A dogmatic, cold, and distant mathematician, Élie de Beaumont appeared to his contemporaries as a misguided pundit—an impression not lessened by his attachment to the theory of elevation craters and to the pentagonal grid, his noncomprehension of the discoveries of Boucher de Perthes, and his unreserved support of the gullible geometer Michel Chasles during the scandal that developed from the latter’s presentation to the Academy of forged manuscripts which he had purchased.

BIBLIOGRAPHY

I. Original Works. Élie de Beaumont’s papers are too numerous to cite individually. A nearly complete list is in the Royal Society of London Catalogue of Scientific Papers, I (1868), 476–479; VI (1872), 648; VII (1877), 607; and IX (1891), 787. Poggendorff, I (1863), 657–658, and III (1898), 404, is incomplete.

The major works were written with Dufrénoy: Voyage métallurgique en Angleterre, ou Recueil de mémoires sur le gisement, l’exploitation et le traitement des minerals d’étain, de cuivre, de plomb, de zinc et de fer dans la Grande-Bretagne, 2 vols. (Paris, 1827); Mémoires pour servir à une description géologique de la France, 4 vols. (Paris, 1830–1838); Carte géologique de la France (6 feuilles), Tableau d’assemblage des six feuilles de la carte géologique (Paris, 1841); Explication de la carte géologique de la France, 2 vols. (Paris, 1841–1848); Description du terrain houiller de la France (Paris, 1842).

II. Secondary Literature. Works on Élie de Beaumont are J. Bertrand, Éloge historique de Élie de Beaumont (Paris, 1875); P. Fallot, “Élie de Beaumont et l’évolution des sciences géologiques au Collège de France,” in Annales des mines, 13th ser., Mémoires, 15 (1939), 75–107.

Additional materials may be found in the Archives Nationales (Paris), F 14.27231, and in the library of the École des Mines de Paris (Élie de Beaumont’s papers).

Arthur Birembaut

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Élie De Beaumont, Jean-Baptistearmand-Louis-L

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