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Buch, [Christian] Leopold von

Buch, [Christian] Leopold von

(b. Stolpe, Germany, 25 April 1774; d. Berlin, Germany, 4 March 1853)

geology.

Buch, one of thirteen children, was born on his family’s estate, about ninety kilometers from Berlin. His father, a Geheimer Legationsrath in the Prussian civil service, spent his leisure time in composing a history of Brandenburg, where the Buchs had been known since the twelfth century. His mother was a member of the famous Arnim family. The family fortune must have been considerable, since Buch’s scientific zeal and passion for travel were never seriously hampered by a need to work for a living. Indeed, throughout his life he wandered extensively and almost at will, much in the manner of the medieval traveling scholar.

When he was fifteen years old, Buch was sent to Berlin to study mineralogy and chemistry for a semester; these studies were a requirement for admission to the Bergakademie, the school of mining at Freiberg. Buch spent three years at the Bergakademie under the guidance of A. G. Werner, who taught lithology and geognosy, and was the chief exponent of the Neptunist theory of the origin of rocks. Alexander von Humboldt was a fellow student, and he and Buch became lifelong friends. After another year’s training in law and government (and incidentally mineralogy) at the universities of Halle and Göttingen, in 1796 Buch entered the Prussian civil service as an inspector of mines, and was commissioned to make a geognostic survey of Silesia.

Although Buch performed some early chemical experiments, like most of Werner’s followers he disliked chemistry, whose “despotic aid was in no way requisite for the independence of mineralogy.” Chemistry could at most be of practical value, and the furnace only provided information on the commercial value of ores. The real scientific interest of minerals lay in their intrinsic substance or essence, with which true mineralogy ought to concern itself. Buch stated that, in accordance with what he had learned from Werner, the specific gravity, hardness, cleavage, color, and luster of a mineral belong to the mineral itself, whereas chemical reaction was no more than an external activity (although he did use muriatic acid to distinguish between calcite and dolomite).

A good exposition of Werner’s natural system was given by D. L. G. Karsten, another of Werner’s students, who arranged a well-known private mineral collection and provided a two-volume catalogue raisonné for it. Both collection and catalog were bought by the Irish Academy of Science, whose president, Richard Kirwan, exclaimed, according to Buch, that only by studying both had he come to understand true, and hence Wernerian, mineralogy, whereupon he abandoned his chemical pursuits.

Chronology was of little importance for the Wernerians. Their willful neglect of this fundamental aspect of geology is partly explained by the tenets of Naturphilosophie—although few geologists actually studied Schelling and Hegel, whose philosophy may be considered an attempt to state explicitly what was implied in the thought of many during the Enlightenment. What Hegel has to say about geology is particularly revealing. He derides the simple conclusion that of two superimposed layers, the higher must be of later formation. It is, he says, as if someone looking at a house concludes with profound wisdom that the ground floor was built first, then the next floor above it, and so on. Hegel goes on to say:

But this sequence contains something more profound. The meaning and the spirit of the process is the intrinsic connection, the necessary relation of these formations whereunto the “after-each-other” adds nothing at all. The general law of this sequence of formations has to be understood, without need for any form of history; this is the essential…. It is Werner’s great merit, to have drawn attention to this sequence and to have looked at it throughout with correct eyes. The internal connection exists in the present as a “side-by-side” and this connection must depend upon the quality, upon the content of these things themselves; the history of the earth is thus on the one side empirical, on the other side concluded from empirical data. To determine how things were millions of years ago (and there we may be free with years) is not interesting, the real interest being confined to that which is now in existence—to this system of different formations [Encyklopädie, pt. 2, sec. 339, Zusatz].

Naturphilosophie here warns against finding out how the things that we see came into being, but encourages us to study the relationships of such things to see whether and how they are mutually consistent (whatever consistency may mean in the case of geological formations). These mysterious relationships had some part in Buch’s unflagging interest in superposition; they led him to his conclusion, on seeing a formation of micaceous schist that was covered in one exposure by slate and in another by sandstone, that the schist could not in these two occurrences be the same, although he could find no perceptible difference.

Naturphilosophie was not wholly harmful in its influence on geology, however. The idea of plumbing essential relationships stimulated geologists in their task of classifying minerals. It must likewise have acted as a stimulus to field geology, holding out as it did a promise of revealing the portentous thoughts of the World-Spirit. Werner’s students were so zealous, d’Aubuisson tells us, that they ran out into the mountains as soon as classes were over. Moreover, for practical purposes the skill to recognize and name rocks and ascertain their distribution in the terrain, coupled with the empirical knowledge of their association with ores, coal, and salt, led to excellent results.

The Neptunist system was in principle very rigid. The primitive rocks—granite, gneiss, and micaceous schist—were deposited in that order, followed by the Floetz formations, graywacke shale, and limestone. These were followed by alluvial deposits and the products of volcanoes. In practice, this theory was a bit more flexible; Werner modified it by adding a transition formation that fell between the primitive rocks and the Floetz formations and that could consist of slate, marble, and so forth. He also allowed for intercalation of all kinds of rocks as accidental formations. Only the independent (selbsländige) formations had to conform to the rule that, according to Werner, must hold everywhere on earth. He believed that this rule about the right order of succession was necessarily true and did not have to be verified outside Saxony. This is in line with the claim of Naturphilosophie that all significant features in nature could be deduced by logic alone.

The height at which a given formation occurred was of great importance, and on many of his trips Buch measured relevant heights. “With due precautions,” he said, “I have hardly any trouble in carrying a mercury barometer with me.”

In principle, only granite could form the highest mountains, being the first rock deposited before the universal ocean withdrew from its highest level. As the water level descended, other formations would be deposited in their proper order. What is most baffling today is the notion that mountains and valleys were at once formed in their present shapes and positions. Steep precipices of a granite mountain were ascribed to chaotic conditions in the primitive ocean. Gneiss could be deposited—like crystals in a beaker—on such a vertical wall, its streaky pattern thus standing on end.

This was the original and most rigid version of Werner’s theory: many incongruous elements had to be brought in to account for what is actually observed. Buch showed great versatility and some originality in applying a startling number of odd and drastic devices. He was grievously unlucky in these guesses and rightly complained of frequent disappointments.

An awkwardness existed in the trees that were found in some coal mines, standing upright in the position in which they had grown. Since this could not have happened under water, the Neptunists were forced to postulate a previous withdrawal of the ocean from all altitudes above those of the mines, and then to hypothesize a return of the water to explain younger formations covering high mountains. They supposed that large caverns in the earth could in turn drain and fill the oceans. Buch found this idea attractive, since the currents in the ocean could then be used to explain the positions of some rock formations.

One of Buch’s earliest geognostic publications (1797) dealt with Landeck, a corner of Silesia on the Bohemian frontier. The paper aroused a great deal of interest, and was translated into French and English. In it, Buch provides a Neptunist interpretation of the region and states that the area, which is enclosed on all sides by mountains, had once been a lake. The lake had overflowed at a point on the east side of the area, and a valley, through which the Landeck area is now drained, had been carved out there by erosion. (In later years Buch stubbornly denied that erosion could modify a landscape to any extent.) The mountains that surround Landeck are composed of primitive gneiss and micaceous schist, except for a gap in the northern corner of the area. In this corner, the mountains are composed of the same Floetz sandstone that covers the Landeck plain. In the northern corner the sandstone reaches 500 meters above its general level. Buch’s conjecture was that the sandstone came down from the north and in rushing through the gap in the primitive mountains dammed itself up to such a height.

Leaving Silesia in September 1798, Buch set out on a walking trip to see Italy, especially Vesuvius, with his own eyes. While the Napoleonic Wars halted him for six months on the northern side of the Alps, he explored the Tyrol, often accompanied by his friend Humboldt. They found a good agreement with Werner’s teaching: peaks of granite in the highest central part, flanked by gneiss, schist, and limestone in due order. When, in the spring, Buch was able to cross the Brenner Pass, he expected to find a symmetrical arrangement on the south side; to his distress, he found quite different formations with enormous masses of porphyry and dolomite. The whole of Werner’s beautiful system collapsed in confusion. The device that Buch had used to impose order on Landeck came to his aid once again. Clearly, what had happened was that on the northern side of the pass the formation flood that had brought the gneiss, schist, and limestone had come, naturally enough, from the north and had been stopped by the granite mountains, which, according to Werner’s theory, were already there at their full height. The floods from the south had arrived independently, at other stages in the workings of nature, and hence had brought other rocks. (This idea of damming up the formation floods recurs several times in Buch’s work—for example, the Trauf, an escarpment that forms the northwest edge of the Jurassic system in southern Germany and consists of coral limestone, was considered to have been an effective barrier reef against floods coming from the south.)

As Buch continued his journey through Italy, the French campaign kept him near Rome for eight months. The imposing remains of extinct volcanoes proved so refractory to Werner’s theory that Buch complained, “Only two days at Vesuvius and all this confusion could be set right.” But when he had wandered around Naples for eight weeks, he wrote to the editor of Gilberts Annalen der Physik: “My friends who believed that after seeing a real volcano, I now could say something definite on the diverging opinions about our basalts, will be badly disappointed.” This refers to the battle over basalt, in which almost everyone with a claim to general knowledge took sides—although, regarding the whole of Werner’s and Hutton’s conflicting theories, basalts generally were not the most important issue.

From 1801 to 1803 Buch worked near Neuchâtel, and in the spring of 1802 he went to the Auvergne for six weeks. This excursion has often been referred to as momentous in bringing about Buch’s alleged conversion to Volcanism and even to Plutonism.

In Auvergne, Buch found hemispherical elevations that lacked craters and correctly interpreted them as tholoids. He was struck by the frequent eruptions of lava near the bases of volcanoes, and theorized that the flanks of the volcanoes were formed by thin strata of the country rock that had been heaved up to form the tentlike roof of a large conical cavern filled with lava. Buch’s theory of elevation craters was given considerable attention in the nineteenth century, although today it is not easy to see exactly what he meant by the term. He sometimes asserted that the elevation crater is not a volcano, and that it lacks a crater proper; a volcano may be spoken of properly only when a crater, and thus a direct channel to the interior of the earth, is present.

In Italy, Buch had looked in vain for the combustible matter—coal or pyrite—that, according to Werner, was necessary for volcanic action. In Auvergne he found volcanoes standing immediately upon granite, which precluded the presence of other, deeper rocks. He was then led to suppose that the granite was transformed into Domite, a type of trachyte found in the Puy de Dome, and then in a continuous action changed into basaltic lava.

Buch’s observational work was much better than his speculations. Both in Auvergne and elsewhere he recorded hundreds of observations with touching fidelity, irrespective of the hypothesis that each might support or gainsay. His writings, however, flatly contradict the facile assertion that he arrived in Auvergne a Neptunist and returned a Volcanist. While it is true that he had to concede that the basalt in Auvergne had been a lava, he could not believe that the basalt in Saxony was of the same origin. (Today these basalts are interpreted as sills, according to Hutton’s ideas on subterranean or Plutonic lava intrusions. Buch could not have held this view because of the important amount of erosion necessary for these sills to be visible.) In Saxony, such mighty masses of lava would have had to have been the product of correspondingly large volcanoes, the absence of which compelled him to seek other origins because Buch, like other Neptunists, excluded the action of erosion. (Werner himself was more tolerant in this respect and did not object to the concept of an original continuous deposit of basalt that later came to be separated by erosional valleys.)

Buch further objected to the idea of a lava flow stopping at the edge of a flat hill top. Why, he asked, did it not flow on down the slope? He judged the steep precipices, formed by columns of basalt tens of meters long, to be as alien to the idea of the end of a lava flow as to the (in his opinion) exclusively gentle slopes made by erosion. The Neptunist concept of precipitation—which could often be sharply delimited by a slight change in the substratum—explained this phenomenon to Buch’s satisfaction. This provides a striking example of Buch’s persistent denial of the effectiveness of erosion, a denial that would seem to have become more stubborn with the years if we compare this with his 1797 explication of the valley that drains Landeck.

Buch published the results of his explorations in Geognostische Beobachtungen auf Reisen durch Deutschland und Italien, which appeared in two volumes (1802, 1809). This work was primarily of geological interest, although much of Buch’s later work may be considered a part of the belles letters of the century. (An earlier short work on kreuzstein, or harmotone, is the only one that has crystallography as its main subject.)

In 1806, when he was thirty—two, Buch was elected a member of the Royal Academy of Berlin. (In due time he was elected a member of academies in Paris, London, and Vienna, while scores of minor scientific societies competed to offer him honorary memberships.) In his speech to the Berlin Academy, Buch spoke of fundamental principles. He presented the interplay of natural forces as one great onward movement that unified all things, from the crystallization of granite to the highest strivings of human intelligence. No deity of any description played any part in this scheme of things; religion was apparently the least of Buch’s concerns.

Buch continued his travels, making a lengthy visit to Scandinavia in 1806 and 1807. In 1815 and 1816 he visited the Canary Islands. In two books of travels, Reise durch Norwegen und Lappland (1810) and Physikalische Beschreibung der Canarischen Inseln (1825), geological data occupy a modest space among Buch’s observations of the landscape, climate, flora and fauna, customs of the inhabitants, and vicissitudes of the road.

His explorations in the southern Alps had suggested to Buch that the towering height of the Dolomites might be the result of upheaval, for which he sought the active agent in porphyry, including monozite. He concluded that the magnesia in which this rock is rich would also have been active in transforming the original limestone into dolomite. Buch thus came to visualize great subterranean activities; in 1815, in the Canary Islands, he ingeniously demonstrated the interdependence of the volcanoes of the archipelago. Since two volcanoes never happened to erupt at the same time, he argued that eruption of one volcano relieved the pressure upon the others. Hence, the masses of material underneath all the volcanoes may be seen as filling one cavern, by which the volcanoes are interconnected.

Buch’s view of effective subterranean masses soon grew to encompass the whole world. A treatise of 1842, “Ueber Granit und Gneiss,” illustrates the later development of Buch’s Wernerism and demonstrates the remarkable consequences to which his refusal to consider erosion led him. Granite and gneiss cover southern Finland and Sweden, while, stretching west from Leningrad, Silurian strata cover the Baltic provinces and the isle of Gotland, and further recur in six small patches in Sweden. These latter, we would now say, represent erosional remnants, hills a few hundred meters high in which the Silurian strata are horizontal, as they are in Gotland and Russia. Buch was compelled to admit that the Silurian strata in the six hills are a remnant of a continuous sedimentary layer that had once extended through a large part of Sweden, but was hard pressed to account for the disappearance of the greater part of it. Since he could not explain it by erosion, he had recourse to the novel, non-Wernerian principle of metamorphism. In Buch’s conjecture, the Silurian rocks had been metamorphosed by the action, probably vaporous, of the underlying granite. This theory further served to explain the scarcity of granite in Scandinavia, about which Buch had worried a great deal; the granite is largely hidden from view by the large Silurian deposits that now appear as gneiss.

The basalt-topped hills were pushed up by a subterranean mass of basalt; the sheets on top thus represent possibly fiery extrusions. Buch thought that the lower mass of basalt, situated between the granite and Silurian layers, served as a shield against the metamorphic action of the granite and thus preserved the Silurian layers in their original state. He concluded that the large parts of Russia covered with nonmetamorphosed Silurian strata must be underlain by basalt.

Buch dismissed as nonsense the notions that the stairlike outline of these hills could be due to weathering and erosion and that the relative height of the hills was due to protection by the more resistant basalt. On one of the six hills, Kinnekulle, no more than a mere dot of basalt is visible at the center of the uppermost Silurian layer; how, Buch asked, could this have afforded protection? Buch conceded that the Silurian layers in all the hills had once been continuous, but it is hard to understand what, in his view, had become of the missing segments. He believed that these rocks must have been reworked by metamorphism, but how they were brought down from the steps of the staircase is not explained. His account of the area is marked by his keen eye for geological observation, trained by Werner, but as soon as past events are brought into consideration, all is dim and misty. It might have been better if Buch had followed Hegel’s advice and refrained from peering into the past.

Buch’s somewhat more actualistic view of sedimentation displayed in this instance may have been the result of his extensive work in stratigraphy and paleontology. This had been Buch’s chief concern since his fiftieth year. His first major achievement in this field consisted in distinguishing between ammonites and nautilidae (1829, 1839) and observing the intricate suture lines in the former. The Wernerians, trained as they were in thoughtful observation and accurate description, soon felt at home with paleontology. We may imagine Buch’s delight as he contemplated the orderly succession of faunas, the characteristics of each being in part determined by its predecessors, and all bearing witness to that great onward movement he had enlarged upon in the speech to the Berlin Academy. He was aware of the value of guide fossils, and sought to enhance their usefulness with careful drawings and descriptions.

Buch’s fundamental error, perhaps, sprang from the prejudice, older than Naturphilosophie, that the earth was specially created as a place for man to dwell in. Hegel’s comparison with a house is suggestive of how time could be considered unimportant and of motives that might lead to the rejection of all except the barest minimum of erosion. It is not very interesting to know how long it took to build the house; we are interested in its present state and whether it is appropriate to our purpose. If we have to think about the building operations, they surely were carried out according to a plan. It would serve no purpose to build some walls with the intention of demolishing them in order to use the stones for other walls. The idea of a purposeful construction bars access to the principle of uniformity.

For more than forty years Buch brooded over one specific problem, that of the erratic blocks distributed over Germany. In southern Silesia, Buch had determined that these blocks came from the Sudets; he had identified the kinds of rocks and observed that they became smaller as they occurred in more northern locations. Farther north, there appeared blocks of a kind alien to the mountains of the south; Buch could but conclude that these, strewn copiously over half of Holland and large parts of Germany and Poland, had been brought from Scandinavia. He was, however, unable to decide what agent had brought them, and felt inclined to attribute their presence to the then rather commonly invoked mighty floods. In Switzerland, erratic blocks from the Alps were found in the Juras, at an appreciable height above the intervening Swiss plain; J. A. de Luc held that these had been hurled through the air by great explosions. Buch objected to this unlikely device, and judged it impossible that blocks from Scandinavia should have been so hurled across the Baltic Sea far into Germany. He further opposed the notion (propounded by Hutton and Agassiz and Charpentier) that the blocks had been transported by glaciers, and explained the polished surfaces of the rocks by ascribing them to differential movements along the curved, onion-like partings generally seen in fresh granite. He even contended that he had seen the same polish on a surface just laid bare by quarrying. Swedish scientists had measured the striae on the polished rocks to determine the direction of transport; Buch halfheartedly agreed with them, since they cited currents as a moving agent. But when Berzelius, among others, concluded that the masses carried southward must represent an appreciable erosion of the land in Sweden, Buch would have no part of it. However intimately he might have come to know the enormous volumes of Mesozoic and Tertiary formations, he apparently refused to give a moment’s thought to where these masses might have come from.

Buch, who never married, referred to himself as a wandering hermit. In later years, however, he got over his shyness in joining larger parties, and when, around 1830, scientists began to meet on field trips, Buch regularly attended. For example, in his last summer he met with naturalists in Koblenz, with Swiss geologists in Sion, with French scientists in Metz, and with German naturalists in Wiesbaden. He then traveled through Basel to Le Puy, where he had an appointment with Daubrée to study the basalt of the Vivarais. In the late autumn he was in Paris with Mitscherlich and Rose; Rose accompanied him back to Berlin by train.

Buch was free of all anxiety that others should unfairly profit from his accomplishments; in the accounts of his journeys, each new phenomenon is recorded either as a matter of fact or as something first observed by a companion. An extreme example was his anonymous publication, in 1826, of a geological map of Germany, which embodies the solid core of a long life’s work. This map, which covered forty—two sheets, was reissued in 1842.

Buch’s many published works are written in a highly attractive style that easily conveys his thoughts. His proficiency as an author enables us to learn of the theory and practice of Neptunism, about which the scarce and constrained writings of Werner tell us little.

A week before his death Buch was with friends in the Humanist Club until late at night. He complained of nothing more severe than chilblained toes, but the next day his first serious illness set in. He was buried in the Buch family vault at Stolpe.

BIBLIOGRAPHY

I. Original Works. Buch’s works were brought together as L. von Buch’s gesammelte Schriften, J. Ewald, J. Roth, H. Eck, and W. Dames, eds., 4 vols. (Berlin, 1867–1885); Vol. I contains J. Ewald, “Leopold von Buch’s Leben und Wirken bis zum Jahre 1806,” pp. v-xlviii. For the individual works listed below, the Roman and Arabic numerals in parentheses refer to the Gesammelte Schriften.

Among Buch’s works are “Mineralogische Beschreibung der Karlsbader Gegend,” in kohler und Hoffmann Bergmannisches Journal, 5 , pt. 2 (1792), 383–424 (I, 3–23); Beobachtungen über den Kreuzstein (Leipzig, 1794) (I, 24–35); Versuch einer mineralogischen Beschreibung von Landeck (Breslau, 1797) (I, 38–72); “Considérations sur le granite,” in Journal de physique, 49 (1799), 206–213 (I, 101–108); “Mémoire sur la formation de la leucite,” Ibid., 262–270 (I, 109–117); “Sur les volcans,” in Bibliographia Britannica, 16 (1801), 227–249 (I, 132–142); Geognostische Beobachtungen auf Reisen durch Deutschland und Italien, 2 vols. (Berlin, 1802–1809) (I, 143–523); “Ueber das Fortschreiten der Bildungen in der Natur,” his inaugural address to the Königliche Akademie der Wissenschaften (17 April 1806) (II, 4–12); Reise nach Norwegen und Lappland (Berlin, 1810) (II, 109–563); Physikalische Beschreibung der Canarischen Inseln (Berlin, 1825) (III, 225–646); and “Ueber Granit und Gneiss,” in Abhandlungen der Königlichen Akademie der Wissenschaften, Berlin (1844) (IV, pt. 2, 717–738).

His unpublished diary is in the possession of the geology department of the University of Berlin. Buch was responsible for the first geological map of Germany (1826), although it does not bear his name. Consisting of forty-two sheets, it was the first map of this sort to cover a fairly large area of Europe. It was reissued in 1842.

II. Secondary Literature. Works on Buch are H. von Dechen, Leopold von Buch; sein Einfluss auf die Entwicklung der Geognosie (Bonn, 1853); S. Günther, A. v. Humboldt, L. v. Buch (P), Vol. XXXIX in the series Geisteshelden (Führende Geister) (Berlin, 1900), 185–271; W. Haidinger, “Zur Erinnerung an Leopold von Buch,” in Jahrbuch der Kaiserlich-Königlichen Geologischen Reichsanstalt, IV (1853), 207–220; G. F. Hegel, Encyklopädie der philosophischen Wissenschaften, 3rd ed. (Heidelberg, 1830), pt. 2, “Die Philosophie der Natur,” sec. 339, Zusatz; H. Hölder, Geologie und paläontologie in Texten und Geschichte, II, pt. 11 of Orbis Academicus; Problemgeschichten der Wissenschaft (Freiburg im Breisgau, 1960), see Index; and R. Hooykaas, The Principle of Uniformity in Geology, Biology and Theology, 2nd ed. (Leiden, 1963).

W. Nieuwenkamp

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