Jean-Baptiste Élie de Beaumont was a French geologist and engineer. He prepared the great geological map of France in collaboration with the French geologist Ours Pierre Dufrénoy.
Background
Jean-Baptiste Élie de Beaumont was born on September 25, 1798, in Canon, Calvados, France. He 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.
Education
Under the Empire, Élie de Beaumont’s parents, who were living at Canon, engaged a Benedictine monk, Dom Raphaël de Hérino, to serve as tutor to him and his brother, Charles-Adolphe-Eugène. 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 Collège Royal Charlemagne. At this collège he obtained fourth honorable mention in elementary mathematics in the general competition of 1816.
In 1817, after a year of higher mathematics at the Collège 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 students from the last three graduating classes. He entered the École Royale des Mines on November 15, 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 processes 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.
Career
During the summer of 1821 Élie de Beaumont 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 January 1, 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’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.
On July 6, 1794 the Committee of Public Safety issued a decree 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 December 5, 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 director-general of bridges, highways, and mines. On June 11, 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 June 15, 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, promoted to mining engineer on June 1, 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 April 25, 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 September 1, 1824 to the Service des Mines at Rouen and placed in charge of the Seine-Inférieure (now Maritime) and Eure departments. 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, noting their observations on Cassini de Thury’s map, drawn up on 180 sheets on a scale of 1 fine 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 December 20, 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 June 22, 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, 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 of systems to twelve. In 1834, at the Société Géologique de France, 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 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 stated, 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 Élie de Beaumont devoted his course at the Collège de France to volcanic and metalliferous emanations; he continued it on July 5, 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 lfis surveys for the geological map.
On May 5, 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.
Élie de Beaumont was director of the Service de la Carte Géologique from its orgamzation 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.
Membership
Élie de Beaumont was one of the founders of the Société Géologique de France in March 1830. On December 21, 1835 he was elected to the Académie des Sciences, in the mineralogy section; on December 19, 1853 he was named perpetual secretary for the mathematical sciences, replacing Arago.
Personality
A dogmatic, cold, and distant mathematician, Élie de Beaumont appeared to his contemporaries as a misguided pundit.
