Abraham Gottlob Werner was a German geologist who set out an early theory about the stratification of the Earth's crust and propounded a history of the Earth that came to be known as Neptunism.
Education
According to his own “Biographical Notes, ” Werner received his first formal education from his father, who encouraged his early interest in mineralogy.
He also studied with a private tutor before entering the Waisenschule at Bunzlau (now Boleslawiec, Poland) at the age of nine.
After five years of this work, in 1769, Werner was enrolled in the recently founded Bergakademie Freiberg and began studies intended to prepare him for the administration of the Duke of Solm’s ironworks.
However, in Freiberg, he was induced to enter the Saxon mining service; and since no one could expect to achieve an advanced position in the service without a degree in jurisprudence, Werner left the Bargakademic after two years to enter the University of Leipzig, where he studied for three years.
During his first two years at the university, he devoted himself mainly to the necessary courses in law, but he became increasingly interested in the study of languages and what is now called historical linguistics, and his interest in mineralogy persisted, until he abandoned the study of law altogether, leaving the university in 1774 without a degree.
Career
In 1773, however, he had written his first book, Von den äusserlichen Kennzeichen der Fossilien, which was published in 1774.
During his forty-two years there, largely because of his fame as a mineralogist and his skill as a teacher, the little mining academy became one of the most famous schools in the world.
His first important mineralogical work, however, Von den äusserlichen Kennzeichen der Fossilien, was not a mineral system but a classification of external characteristics of minerals, designed to aid the worker or the student in the field.
And finally, its identification is not aided in any way by placing it, in lectures and mineral collections, among earth pitch, the three coal species, graphite, and so forth; but it is helpful to place it with the far more similar zircon and the other gems.
Werner accepted the offer, joining the faculity in 1775, and remained at the school for the rest of his life.
He moved in a brilliant circle of friends and was received at the Saxon court.
During his last years he suffered increasingly from ill health, going frequently to take the waters at various health resorts.
He also attempted to establish some standards of quantification and thus to clear away the vagueness in the terminology, then in use.
As chemistry and crystallography developed, mineralogists came to rely more on chemical analysis and less on external characteristics, but Von den äusserlichen Kennzeichen der Fossilien, published when werner was twenty-five years old, continued to be an important work into the nineteenth century.
Thomas Weaver’s translation into English was published in Dublin in 1805, and a revised translation by Charles Moxon appeared in 1849.
Werner remained convinced of the importance of external characteristics, not only in the identification of minerals but also in the study of their composition.
On the other hand, he recognized that external characteristics cannot form the basis of a mineral system.
He was convinced that ultimately mineral systems must be based on chemical composition, and to that end he kept abreast of developments in chemistry and helped to bring about the building of a chemical laboratory at the Bergakademie and the engagement of W. A. Lampadius as teacher of chemistry.
A good example is his classification of the diamond among the earths rather than the combustibles, even though he was well aware that the diamond is a carbon.
Werner considered crystallography to be only a branch of mineralogy, which, although important to the study of mineralogy, is unsuitable as a basis for a mineral system and of limited practical value.
However, he did study crystallography himself.
He emphasized its importance in his lectures, and urged his students to study it.
He was well acquainted with the work of Romé de l’Isle and Haüy, being especially interested in the study of primary crystal forms, especially with what Haüy came to call laws of decrement (décroissement).
His fullest exposition of his ideas on this subject was published without his permission in 1816 under the title “Werner’s oryctognostische Classifikationslehre. ”
Werner believed that there are only two possible kinds of kinship among minerals.
One leads to a complete transition, or Ubergang, in which “the crystalliztion suite of one species is so closely related to that of another that both are able to cross over completely into the other. ”
In the other, which he called Aneinanderstossen (“coming in touch with one another”), the minerals are related to one another interruptedly, making a complete transition impossible. Werner’s mineral system, complete as it stood at the time, was published three times, once in 1789, once in 1816, and again in 1817.
In addition, parts of it appeared incorporated in other works.
In 1780 Werner’s partial translation of Axel Cronstedt’s Försök til Mineralogie was published.
Werner believed that, at the time, Cronstedt’s work was the best available on the subject.
His comments and additions so enlarged Cronstedt’s work that his translation became a textbook of mineralogy in its own right and was widely used as a teaching aid and reference work. In 1791-1793 Werner’s two-volume catalog of Pabst von Ohain’s mineral collection appeared.
In the article Werner emphasized that a mineral collection should be more than a systematic arrangement of minerals: it should further the understanding of the entire mineral kingdom.
He therefore cataloged Pabst von Ohain’s collection in five separate collections according to external characteristics, the natural order of minerals in a mineral system, the historical development of the earth’s crust, the places of origin of minerals, and the uses of minerals.
Von Ohain’s collection was ultimately sold to the government of Portugal and shipped to Brazil, where it was used in the teaching of geology and mineralogy in Rio de Janeiro.
And the catalog, which was widely used in Europe, was one of the important avenues through which Werner’s influence on mineralogy and geology was spread. None of the complete editions of Werner’s system was prepared by Werner himself.
It was also Hoffman who, along with another student, A. W. Köhler, revised the system in 1812 (this is the version which was published in 1816).
The most striking difference between them is that the earlier work covers only 183 species, whereas the later one covers 317.
Of these 317, Werner had independently discovered eight and had given names to numerous others.
The names of the eight minerals that he discovered, as well as twenty-six other names which he employed, are still used today to designate the same minerals to which Werner applied them.
Werner’s scientific life spanned a time of unusual interest in mineralogy, an interest not confined to scientists but fostered to a large extent by romantic conceptions on the one hand and utilitarian considerations on the other.
The store of mineralogical knowledge was rapidly increasing; and advances in chemistry, crystallography, and geology were opening new paths for the study of mineralogy.
Through his teaching and writing he contributed greatly to the dissemination of knowledge.
Thus, Werner was a steadying influence at a time of great and varied activity.
Werner’s interest in historical geology stemmed partly from his interest in mineralogy and partly from his interest in mining.
A list of writers on geology that he prepared includes among others Steno, Lehmann, Ferber, Hamilton, Füchsel, Saussure, Buffon and Moro.
His own ideas were undoubtedly influenced in one way or another by what he had read and, in fact, his theories bear a rather striking resemblance to those of Steno, with whose work he was apparently familiar.
But whatever the background of his theories.
Werner thought, on the basis of the geological knowledge of his day, that they were firmly supported by the evidence—a fact which goes far to explain the popularity of his system.
Unlike Steno, Lehmann, Moro, and many other earlier and even contemporary writers on geology, he felt no need to fit his theories into the biblical story of creation.
There is no indication in his writings, published or unpublished, that any of the floods which are an important part of his theory was the biblical flood.
Thus, although his theories, being basically neptunistic, were more acceptable to the defenders of the biblical account of creation than those of the vulcanists, he himself was in no way engaged in the religious aspects of the controversy.
The two basic postulates of the Wernerian theory were that the earth was once enveloped by a universal ocean and that all the important rocks that make up the crust of the earth were either precipitates or sediments from that ocean.
Werner placed the rocks in four (later five) classes according to the period in which they were formed, believing that characteristics of the rocks were the result of the depth, content, and conditions of the universal ocean at the time when they were formed.
His classification was basically historical.
As he himself put it.
Although he did not conceive of the immensity of geological time on the same scale as present-day scientists do, he did write of a time “when the waters, perhaps 1, 000, 000 years ago, completely covered our earth …” and in his lectures he spoke of the history of the earth “in contrast to which written history is only a point in time. ”
In order to discover the time sequence of rock formation, he used various means, such as compositional and textural features and, especially, the structure of rocks and stratigraphic relations, which he considered the most important clues to the understanding of the history of the earth’s crust.
His theory included two unexplained general risings of the universal ocean as well as some local floods; but he believed that, in general, the waters had receded very slowly but steadily.
The four periods of formation and their corresponding classes of rocks were the primitive, the floetz, the volcanic, and the alluvial.
At the beginning of the primitive period, according to Werner’s theory, the universal ocean was very deep and calm; and the first rocks were chemical precipitates which adhered to an originally uneven surface, granite being the first rock formed.
Gradually the waters became less calm, so that later rocks of the primitive period are not as crystalline as the older ones; and toward the end of the period there was a general rising of the waters, followed by a comparatively rapid recession, which explains the position of some of the later primitive rocks relative to the older ones.
Once again there was a general inundation, with the waters this time reaching a greater height than ever before.
It is with these variations from stormy to calm to stormy and the general inundation that Werner explains the relative position of the floetz rocks and their often broken stratification.
The volcanic and alluvial periods are almost contemporaneous and both extend into the present (as does the floetz period).
The volcanic and alluvial rocks, however, are not deposits from the universal ocean but the result of local conditions.
Werner added the transition period and the class of transition rocks to his system after the discovery that some rocks which he had previously classified as primitive contain fossils.
According to his explanation, the relatively low-standing waters toward the end of the primitive period were calm at first, but gradually they became increasingly stormy, destroying some of the previously formed rocks as well as some living organisms, which had just begun to develop.
The rocks of the first three periods, which constitute most of the earth’s crust, were precipitates or deposits from the universal ocean, those of the two later periods the result of local conditions.
Since Werner believed that the contents of the universal ocean had varied from time to time and from place to place, his theory could account for variations from the general principle that the rocks had been laid down by the universal ocean in layers one above the other.
For instance, if the essential contents had at some time been missing from some part of the ocean, an entire formation might be missing from the corresponding area of the earth’s crust.
Also, there is nothing in the theory to preclude the formation of similar rocks at different times.
Thus, it is only in an idealization of the system that the rocks of the earth’s crust can be envisioned as enveloping the earth in layers much like the layers of an onion.
In fact, the theory was flexible enough that, with the addition of factors such as differential settling and the subsequent effects of erosion, cave-ins, etc. , it could explain virtually all the phenomena which were observable in Werner’s time.
By the academic year 1778-1779 he had recognized that he could not cover this theoretical part of the course as thoroughly as he wished in one year and at the same time give sufficient practical instruction.
He therefore announced that he would offer the theoretical introduction as a separate course entitled “Lehre von den Gebirgen, ” Although this was the course which eventually attracted students from all over Europe and from the Americas, bringing fame to the Bergakademie and spreading Werner’s theories, it did not attract many students at first; and it was not until the academic year 1786-1787 that it began to be offered yearly.
In the meantime, Werner had written his “Kurze Klassifikation und Beschreibung der verschedenen Gebirgsarten, ” which was published in the 1786 volume of Abhandlungen der Biihmischen Gesellschaft der Wissenschaften and subsequently in at least two pamphlet editions. Short though it is, the “Kurze Klassifikation” is important to the history of geology for a number of reasons.
Although it contains no discussion of Werner’s theories, it exemplifies them; and it is the only printed presentation of those theories to come from Werner’s own hand.
The principle of geologic succession is implicit in it.
The rocks are classified according to the period of formation, and virtually all are assumed to be of aqueous origin.
It gave clear definitions of rocks, many of which had not previously been generally agreed upon.
And it inspired the research of many geologists, including many who did not accept Werner’s theories, well into the nineteenth century.
But the “Kurze Klassifikation” is also important in another way.
In a note on the section dealing with volcanic rocks, Werner asserted for the first time that all basalt is of aqueous origin, thus precipitating the great basalt controversy.
Until the end of the eighteenth century, it was generally agreed that granite is of aqueous origin; and many other rocks now considered to be magmatic played only a minor role in discussions of the origin of volcanoes.
Therefore, for a long time, the whole question of the relative importance of fire and water as agents in the creation of the earth’s crust revolved about the origin of basalt, since basalt is so abundant and so widely distributed.
Werner’s assertion received a great deal of publicity, however; and the debate was resumed with a fervor not shown before, as a host of geologists rushed into the field to seek evidence for one theory or the other. As early as 1776 Werner had maintained that not all basalt is volcanic in origin.
He had previously felt that the theory of the volcanic origin of basalt was “paradoxical, ” and an examination of the basalt mountain at Stolpen in Saxony had convinced him that that formation at least was of aqueous origin.
In the spring of 1787, he examined the basalt deposit at Scheibenberg, in the Erzgebirge, where he found layers of sand, clay, and wacke below basalt.
He took this as indisputable evidence of the correctness of his assumption and subsequently wrote an article explaining his discovery.
This article appeared in the Intelligenzblatt of the Allgemeine Litteraturzeitung of Jena in the autumm of 1788.
In the meantime, the Magazin für die Naturkunde Helvetiens had offered a prize for the best essay in answer to the question “What is basalt?”
Two of Werner’s students entered entered the competition: J. C. W. Voigt, who advocated the volcanic origin of basalt, and J. F. W. Widenmann, who defended aqueous origin.
With the appearance of Werner’s article, Voigt wrote a letter to the Intelligenzblatt “cor recting” Werner; Werner replied with some heat.
Subsequently Werner wrote seven more short articles on the subject, all but one of which appeared in Bergmännisches Journal in the spring of 1789.
In September of the same year the Magazin fur die Naturkunde Helvetiens published both Voigt’s and Widenmann’s essays in the same issue that carried Werner’s article on the origin of volcanoes.
Widenmann won the prize; but neither essay settled the controversy, and the matter continued to be debated and investigated with keen interest for many years.
Werner, however, took no further part in it except to explain in his Neue Theorie von der Entstehung der Gänge (1791) that basalt veins.
like others, are the result of settling from above. At the time, neither side had any means of proving conclusively that it was right.
Petrography alone could not provide sufficient proof; microscopic methods were not then available; and chemical analysis, which showed great constitutional uniformity among basalts but great diversity among lavas, was hardly convincing.
Werner’s theory was better substantiated by evidence and reasoning than those of his opponents. He trained in his methods of research, who had originally gone out to prove him right, were in many instances in the forefront of the investigations that ultimately proved him wrong. Werner could never bring himself to place basalt among the volcanic rocks.
But in order to remain faithful to his idea of a universally applicable geological system into which all observable phenomena would fit, he had to work out a theory of the origin of ore deposits which would be consistent with his general theory of the origin of the earth’s crust.
The result of his work in this area was the Neue Theorie von der Entstehung der Gäng, published in 1791.
He distinguished between veins and ore beds, giving an explanation which is in principle historical: minerals which occur in veins are very diverse and give every indication that they were formed during different periods than the surrounding rocks, whereas those in ore beds have the same direction as the strata among which they are found, indicating that they are of contemporaneous origin.
He supported this premise on the basis of the structure of veins, comparisons of the structure of veins with that of the country rock, the structure of druses in veins, fragments of country rock in veins, analogy with existing rents, and the laws of mechanics.
In veins they are usually coarser and better crystallized because in veins they were not so much affected by the activities of the waters, and thus the deposition of materials in veins could proceed much more calmly than the depositions in beds and strata.
On the basis of the structure of the vein stuff and the pattern of association of certain minerals, metals, and ores in veins, he tried to establish their relative ages and the sequence of their formation.
and his theory met with opposition even in his own day and was later discarded.
However, many of its elements were of lasting value.
Werner formulated basic questions about the origin and history of veins and their contents, established criteria for determining the relative age of veins and vein materials, and presented a comparative study of the structure of veins and rock masses.
His student Breithaupt was probably the first to stimulate widespread research on the paragenesis of minerals, but it was Werner who set up the problem and gave impetus to a search for a solution.
Perhaps the most important contribution of Von der Entstehung der Gange, however, was that it made the study of vein formation an integral part of historical geology. After the appearance of the second volume of his catalog of Pabst von Ohain’s mineral cabinet in 1793.
Werner published little on geology.
In 1794, he published a fifty-page article, “Über den trapp der Schweden, ” and a lecture which he had given before the Gesellschaft für Mineralogie zu Dresden was published after his death under the title “Allgemeine Betrachtungen über den festen Erdkorper. ”
This work, however, was nothing but the introduction to his course on geognosy.
A collection of works on mining and ferrous metallurgy, for which Werner had written three articles and coauthored another, appeared in 1811; however, all the articles had been written much earlier.
before 1785.
In his later years. He was always surrounded by students and received numerous visitors.
The manuscripts that he left to the Bergakademie are extensive; but during the last twenty years of his life.
his contributions to geology were made known largely by word of mouth.
Yet he remained a towering figure in his field.
Probably no other geologist has ever been so extensively eulogized by followers and opponents alike as he was during the two decades following his death.
Views
He taught that the rocks were the precipitates of a primeval ocean, and followed each other in successive deposits of world-wide extent.
Volcanoes were regarded by him as abnormal phenomena, probably due to the combustion of subterranean beds of coal.
Basalt and similar rocks, which even then were recognized by other observers as of igneous origin, were believed by him to be water-formed accumulations of the same ancient ocean.
R. Jameson, the most distinguished of his British pupils, was for many years an ardent teacher of the Wernerian doctrines.
His work represents the culmination of a long development in mineralogy and the beginning of a new mineralogy, of which he was fully conscious. Although many earlier writers had speculated on the origin of the earth’s crust, Werner is rightly called the father of historical geology, for he was the first to work out a complete, universally applicable geological system.
He explained the formation of rents as a result of diagenetic settling–compaction of the originally wet rock masses and the simultaneous loss of the support of the high-standing waters as these receded–shrinkage, and earthquakes.
Quotations:
He wrote: “One can indeed recognize in the external character of minerals the differences of their composition, provided both are previously determined, but the correlation between these two features cannot be discovered in them. ”
"I had to be guided completely in the classificatory presentation or tabulation of these masses by the discoverable time sequence of the particular formations if I wanted to remain true to my plan to sketch through this classification a foundation for a complete canvass of the universal formation of these masses. "
In this work Werner defined veins as “particular mineral depositories of tabular shape, which in general traverse the strata of rocks …and are filled with mineral masses differing more or less from the rocks in which they occur. ”
He also gave a historical definition of the concept of a vein formation: “I designate all veins of one and the same origin as a vein formation …whether they are close together in one region or widely separated from one another in distant countries, …”13Werner built his theory of the formation of veins on two major premises.
The first of these is that “all true veins are really rents which (of necessity) were originally open and were only later filled from above. ”