Abraham Gottlob Werner

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German mineralogist and geologist (1750–1817)

Werner was born in the traditional mining town of Wehrau, which is now in Poland. Most of his ancestors had worked in some position or other in the industry and his father was inspector of the iron foundry at the town. He began work as an assistant to his father before entering the new Freiberg Mining Academy in 1769. He studied at the University of Leipzig (1771–75) before returning to teach at the Freiberg Mining Academy. There he established his neptunist views on the aqueous origin of rocks and attracted a considerable following.

Werner's neptunian theory explained the surface of the Earth and the distribution and sequence of rocks in terms of a deluge, which had covered the entire Earth including the highest mountains. The rock formations were laid down when the flood subsided in a universal and specific sequence. The first layer consisted of primitive rocks, such as granite, gneiss, and slates, and contained no fossils. The next strata (the transitional) consisted of shales and graywacke and contained fossilized fish. Above this were the limestones, sandstones, and chalks of the secondary rocks and then the gravels and sands of the alluvial strata. Finally, after the waters had completely disappeared, local volcanic activity produced lavas and other deposits.

However, this fivefold scheme, while no doubt applicable in Werner's region of Saxony, presented great difficulties outside the area. There was much that Werner could not explain, such as where the enormous flood had gone to and the presence of large basalt tracts in Europe, which were found in areas free of volcanoes. For many years Werner's theories eclipsed those of the plutonists, led by James Hutton, who emphasized the origin of igneous rocks from molten material. But as knowledge of the strata of Europe increased it became clear that there were too many regions in which Werner's sequence bore no relation to reality.

Yet neptunism certainly had its attractions, with Werner's disciples distributed throughout Europe. The advantages of the theory were that it was theologically acceptable, it was simple, and it showed how the Earth could be formed in the short time available.

Werner was also a mineralogist and he constructed a new classification of minerals. There was a major split among 18th-century mineralogists as to whether minerals should be classified according to their external form (the natural method) or by their chemical composition (the chemical method). Werner finally adopted, in 1817, a mixed set of criteria by which he divided minerals into four main classes – earthy, saline, combustible, and metallic.

The German naturalist Abraham Gottlob Werner (1749-1817) wrote the first modern textbook of descriptive mineralogy and was the major proponent of the Neptunian theory of the earth.

Abraham Werner was born on Sept. 25, 1749, at Wehrau in Upper Lusatia (Prussian Silesia). His ancestors had been employed in the mining industry for several hundred years, and his father was the overseer of a foundry in Wehrau. When he was 10 years old, Werner went to school at Bunzlau, Silesia, but five years later he returned home to become his father's assistant. However, his interest in mineralogy became so strong that he abandoned this practical career and in 1769 entered the Mining Academy of Freiberg. After two years there he matriculated in 1771 at the University of Leipzig.

Investigations in Mineralogy

During his stay at Leipzig as a student, Werner became acutely aware of the unsatisfactory character of the numerous systems used at the time to describe and classify minerals. Two conflicting approaches, based respectively on the chemical composition and on the physical characters of minerals, had created a confused association of unrelated observations, imprecise definitions, and impractical tabular arrangements. In the amazingly short time of a year, Werner wrote and then published Vonden äusserlichen Kennzeichen der Fossilien (1774; On the External Characters of Fossils, or of Minerals), the first modern textbook of descriptive mineralogy. Although Werner recognized that a true and final classification of minerals should be based on their chemical composition, he emphasized that it should be preceded by a method which would allow a precise identification of the various minerals by means of their external characters and physical properties.

Werner's description of the external characters of minerals, which occupies the major part of his book, remains an outstanding illustration of his unusual gift of observation and his knowledge of minerals. However, the quality of his work on mineralogy decreases abruptly with the discussion of the crystalline forms, for he was a practical or applied mineralogist to whom the mathematical aspect of mineralogy was superfluous. He never realized the basic importance of crystallography, which he thought was applied mathematics rather than a branch of mineralogy.

Geognosy and Neptunism

Upon publication of his book on minerals, Werner left Leipzig and returned to his home in Wehrau, where he became involved in the preparation of field trips to collect minerals and visit mines. However, the Mining Academy of Freiberg, strongly impressed by his performance, appointed him in 1775 inspector and teacher of mining and mineralogy. His dogmatic but stimulating teaching filled his students with enthusiasm, and they returned to their respective countries zealously spreading Werner's geological concepts. Therefore, a full account of his ideas is obtainable only through their writings and particularly those of his foremost follower, Robert Jameson.

Werner's concept of the earth's crust may be visualized as an extension of his great desire for rigid classification. He had only contempt for the speculative naturalists who were concerned with theories about the origin of the earth, and therefore he called his subject "geognosy, " or "earth knowledge, " which he defined as the science concerned with the arrangement of minerals in the various layers, and with the relationship of such layers, in order to reach an understanding of the constitution of the earth. He emphatically stressed the precision of his observations but did not hesitate to make sweeping generalizations about the whole earth from his very limited experience in Saxony. He gradually changed his hypotheses into so-called "facts" by the simple process of repeating them many times with unshakable confidence. Therefore, Werner's system, which pretended to avoid speculation, actually became the most speculative and erroneous attempt at explaining the origin of the earth.

Werner subdivided the earth's crust into a series of superposed and distinct "formations." He believed that these formations could be recognized all over the world and would therefore provide the key to the understanding of the geology of any country. He adopted the old idea that the earth originally consisted of a solid core completely surrounded by a universal ocean, which was at least as deep as the highest mountains and contained great quantities of mineral matter. Since the sea played a fundamental role in this system, the name of Neptunism was given to Werner's school. In this universal body of water, chemical precipitation took place, generating and depositing all forms of rocks in a constant succession.

Because Werner did not believe that the earth had any kind of internal fire or other deep-seated source of energy, he was forced to consider volcanic rocks as recent and accidental products, which he explained by means of the old concept of the combustion of underground coal beds. A further strange characteristic of Werner's was his denial of the disturbances of the earth's crust, such as folding or tilting, as proofs of the internal energy of the earth. Beds were supposed to have been deposited essentially in a horizontal position, and those dipping more than 30° were considered as having been "locally disturbed" by processes which were not elaborated upon. This refutation of mountain-building processes as an expression of internal energy was naturally coupled with Werner's equally dogmatic refutation of the occurrence of past volcanic activity.

Origin of Ore Deposits

Werner's ideas on the origin of ore deposits were corollaries of his general theory on geognosy. He stated that mineral veins were due to the filling by precipitates of fissures developed on the bottom of the universal ocean. The fissures were formed either by contraction or by the effects of earthquake movements. Consistent with his negation of the earth's internal fire, he refuted the idea that veins could have been filled by the products deposited by solutions or vapors originating from within the earth. Despite his ever present dogmatism, Werner did, however, demonstrate the value of a geometrical classification of veins, and he also gave excellent descriptions of their internal structures.

In bad health, Werner retired to Dresden, where he died, a bachelor, on June 30, 1817. His death was felt by most of the profession as a relief from a unique example of scientific despotism during which a man of genius tried unsuccessfully, for his entire life, to mold nature into an inflexible framework.

Further Reading

Biographical accounts of Werner are in Sir Archibald Geikie, The Founders of Geology (1897; new ed. 1962); Karl A. von Zittel, History of Geology and Palaeontology (1901); and Frank D. Adams, The Birth and Development of the Geological Sciences (1938; new ed. 1954).

Werner, Abraham Gottlob (ä'brähäm gôt'lōp vĕr'nər), 1750-1817, German geologist. In 1775 he became inspector and teacher in the mining academy at Freiberg, which through his efforts became one of the leading schools in Germany. In the last part of the 18th cent. he was the most notable figure in the investigation of rocks and minerals; he called the new science geognosy and defined it as the study of the layers of mineral matter. He was the first to classify minerals systematically. According to his theory of neptunism, the earth was originally an ocean of water from which were precipitated the solid rocks now forming most of the dry land. Although much of his theory has been rejected, geology is indebted to him for the application of chronology to rock formations as well as for his precise definitions.

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