Charpentier, Johann (Jean) De
Charpentier, Johann (Jean) De
Charpentier, Johann (Jean) De
(b. Freiberg, Germany, 7 December 1786; d. Bex, Switzerland, 12 September 1855),
mining engineering, glaciology.
Charpentier’s father, Johann Friedrich Wilhelm de Charpentier, was a professor at the Mining Academy of Freiberg; his mother was Luise Dorothea von Zobel. He followed the family profession of geology and entered the Mining Academy, which was directed by the famous neptunist Abraham Gottlob Werner, who had also taught Humboldt and Buch.
Graduating with distinction, Charpentier began his career in the coal mines at Waldenburg, Lower Silesia (of which his brother Toussaint was director), where he solved an engineering problem that had baffled Humboldt. From 1808 to 1813 Charpentier traveled in the Pyrenees, where he directed a copper mine at Baigorry. His researches on Pyrenees geology were published in 1823 in a work that received the prize of the Paris Academy of Sciences. In 1813 his friend Charles Lardy, also a student of Werner’s, secured Charpentier the post of director of the salt mines of Bex, in the canton of Vaud.
These salt mines held a special position in the Swiss economy, for they were the only ones in the Confederation and importation of salt was not only expensive but also subject to political conditions, especially if imported from France. The efficiency of the Bex mines was therefore a matter of national concern, and Charpentier was successful in raising it substantially. Instead of continuing the practice of searching for salt springs, he cut galleries into the rock and extracted the rock salt, springs, he cut galleries into the rock and extracted the rock salt, which was taken to basins where water was added to form a saturated solution; it was then pumped into other containers and evaporated.
In 1818 the disaster of the Glacier de Gietroz in the Val de Bagnes (it had dammed a lake which burst through the ice with great loss of life) turned Charpentier’s attention to glaciers. He knew the views of Jean-Pierre Perraudin and of his friend Venetz on the formerly great extent of glaciers and rejected them as impossible; when he investigated them, however, he found to his astonishment that all the evidence supported such views. Immediately behind Charpentier’s house at Les Dévens, near Bex, two hughe blocks of rock lay unconformably on the slope of a hill. He was forced to the conclusion that only one means of transport could have brought these blocks from the mountains behind Bex to their present position: a glacier. (It was not then known on the Continent that this view had been published by James Hutton in 1795, John Playfair in 1802, and Sir John Leslie in 1804). Charpentier then devoted his time to a study of the Rhone valley and basin and the blocks of rock scattered in them all the way from the Alps to the Jura.
Erratic blocks had been recognized in Switzerland by Lang in 1708 and in 1715 by Laurens Roberg in Scandinavia, where Swedenborg and Linnaeus also observed them. The problem was to discover where they came from and how they had come. Some Swiss, such as Louis Bourguet and Moritz Anton Cappeler, thought that they were meteorites; this, however, would fail to explain why they were mineralogically identical with some peaks in the Alps, whence, as John Strange recognized, they had come.
In a masterpiece of absurdity, Jean-André Deluc imagined that there had been caverns in the earth which, when their roofs collapsed, catapulted the blocks—without evidence of the existence of such caverns or calculation of the energy required to hurl 100,000 cubic feet of granite 100 miles, in any case it would not explain why the blocks were spread not in all directions, but in groups opposite the mouths of the valleys containing mountains of similar composition.
This arrangement led many to conclude that the blocks had been brought to their positions by flood waters; this was the view of Saussure, Buch, H. J. C. Escher von der Linth, and Élie de Beaumont, all geologists of repute who failed to consider where such vast quantities of water had come from; where the water had gone; how blocks weighing hundreds of tons could have been moved a hundred miles and, in the Jura, uphill; why such waters had done no other recognizable damage; and why some of the blocks had sharp edges, unworn by rolling.
Another hypothesis ascribed the transport of blocks to icebergs or ice rafts on rivers, lakes, or an arm of the sea. Subscribers to this view included Daniel Tilas (1738), Jens Esmark, Sir James Hall, Charles Lyell, Roderick Murchison, and Charles Darwin. All of them failed to see that the surface of the lake, river, or sea would have had to maintain a constant level for a considerable time; that erratic blocks should be found exclusively at levels at which they were not; and that if some icebergs had floated blocks from the Alps to the Jura, then others must have floated Jura blocks to the Alps—where ther are none.
Charpentier analyzed all of these hypotheses and refuted them with evidence of his own finding. The debacle of the Glacier de Giétroz showed him that masses of water do not move big blocks. To ensure Venetz’s priority in the idea of the previous extent of glaciers, he had Venetz’s paper of 1821, which had been forgotten, printed by the Swiss Natural Science Society in 1833 and himself read a paper before that organization in 1834. It was met with incredulity and scorn.
Undismayed, Charpentier continued his observations and invited the incredulous to visit him and see the evidence for themselves. Among his visitors was Louis Agassiz, who was soon carried away with such enthusiasm for the theory of the Ice Age that he visited a number of glaciers and blocks and rushed into print, ahead of Charpentier, with his Études sur les glaciers 1840. Agassiz asserted that Europe had been covered with ice before the uplift of the Alps; that when the Alps were elevated, they lifted the plate of ice and pierced it in spots, so that blocks slid down the slope from the Alps to the Jura (the slope 1°8’); and that erratic blocks on the Jura were different in composition from those carried by glaciers (he had not observed that some erratic blocks may have been water-worn before they were transported by a glacier). In other words, he denied that glaciers extended from the Alps to the Jura. He also claimed that the stratification of the snowfields was carried throughout the glacier (he mistook the veined structure resulting from pressure for stratification) and that the direction of crevasses at the sides of glaciers, pointing outward and downhill, meant that the sides of glaciers traveled faster than their centers (the opposite of the truth). Agassiz afterward retracted these errors, but such is the power of publicity and enthusiasm that the origin of the theory of the Ice Age is today commonly attributed to Agassiz and not to its rightful scientific parent, Charpentier.
Charpentier received Agassiz’s book on 28 October 1840, three days before he finished his own Essai surles glaciers, which was published in February 1841. The scrupulous care with which he weighed the evidence and described the phenomenon of erratic blocks and the function of glaciers in transporting them makes this book a classic.
There are, however, two aspects of Charpentier’s glacier studies in which he failed. The first is a matter that he rightly saw as of prime importance: the meteorological conditions requisite for the former great extent of glaciers. He saw that glaciers were formed from increased precipitation after the uplift of the Alps; and he sought the cause of this increase in the percolation of water into fissures in the earth’s crust following the uplift until terrestrial heat converted this water into steam and vapor that subsequently fell on the Alps as snow. The problem still awaits solution, even after Robert Falcon Scott’s suggestion that heating of the Arctic Ocean makes its water available for evaporation by winds and deposition as snow.
The other aspect was the mechanism of glacier motion, which Charpentier ascribed to the expansion of water as it falls onto glaciers and is converted into ice. James Forbes of Edinburgh showed that glaciers move even in winter, when all water is frozen; and that when water freezes, the latent of ice melts the surrounding ice in a glacier (he found that the glacier stays at 0°C.). Forbes called on Charpentier in 1844 at Les Devens; and Charpentier, always open-minded toward new evidence, was prepared to admit the correctness of Forbes’s démonstrations.
Charpentier was a man of great personality and charm, always helpful and kind. His home became a place of pilgrimage for men of science to discuss glaciology and to see his great collections of minerals, shells, and plants, which are now in the Lausanne Museum. When his fame had become established, Charpentier received numerous offers to lucrative posts elsewhere but refused them all, preferring to stay in “his” mountains. He had married Thérèse Louise von Gablenz of Dresden, but she died young, during childbirth.
I. Original Works. Charpentier’s writings include Mémoire sur la nature le gisement du Pyroxene en roche, connu sous le nom d’Herzolithe (Paris, 1812); Essai sur la constitution géognostique des Pyénées (Paris-Strasbourg, 1823); “Notice sur la cause probable du transport des blocs erratiques de la Suisse,” in Annales des mines, 8 (1835), 219; and Essai sur les glaciers et sur le terrain erratique du bassin du Rhône (Lausanne, 1841).
II. Secondary Literature. On Charpentier or his work see Jules Marcou, Life, Letters, and Works of Louis Agassiz (New York, 1896); E. Payot, “Souvenirs d’hommes utiles au pays. Jean de Charpentier,” in Revue historique vaudoise (Lausanne)., 21 (1913), 161; and J. C. Shairp, P.G. Tait, and A. Adams-Reilly, Life and Letters of James David Forbes (London,1873).
Gavin de Beer