Im Steinbruch der Zeit. Erdgeschichten und die Anfänge der Geologie

Why is there an exhibition on the early history of geology in the Francke Foundations? There are two reasons for this.
Firstly, there is a cabinet with minerals in the baroque Wunderkammer - and such mineral cabinets belonged in each of these collections at that time, because the stones, the so-called 'inanimate nature', were also considered an important part of nature. Therefore, the exhibition is intended to explore the question of what significance stones and minerals had for the scientific and collecting culture of the early modern period.
On the other hand, the well-known geologist Christian Keferstein (1784-1866) from Halle donated his archive, library and collection of geological maps to the Francke Foundations. This collection has now been inventoried at the Study Center of the Francke Foundations and will be presented to the public in the context of this exhibition.

The exhibition tells the story of the early history of geology, when the natural history scholars became increasingly involved in the »quarry of time« and realized that the earth must be of an age unimaginable at that time. However, at that time they could not determine it exactly. On the other hand, we can find out by a quick look at the corresponding article on wikipedia that our earth is 4.55 billion years old. In determining this age, geoscientists were able to use the most modern technology to measure the radioactive decay of uranium and thus determine the age of meteorites or rocks. The researchers at that time had only their rationality and imagination. The result is a large number of »earth stories« that seem bizarre to us today.

Descend into the »quarry of time« and see the early modern geologists discover in natural history, mining and alchemy, collect and arrange, believe in the story of creation and this belief in nature measure, explore, measure and calculate, understand what their discoveries mean. We release visitors with a thought-provoking impulse to the face of the earth, which for the first time in the Anthropocene changed the face of mankind permanently.

Für alle, die Podcasts lieben, haben wir den Hörrundgang online veröffentlicht und geben Dominik Eulberg das Wort, der die »Erdsounds« für den ersten und letzten Raum der Ausstellung kreiert hat. Die eigens für die Jahresausstellung entstandenen Sounds stellen wir in voller Länge zur Verfügung.

Einen Überblick über die gesamte Ausstellung geben Ihnen die Kuratoren in ihrem zweiteiligen Rundgang:

In the Christian Middle Ages, people believed that the earth created by God was perfect from the beginning and has not changed since then, apart from the devastation once wreaked by the Biblical Flood. The age of the earth was not considered - the chronology of the Bible applied: God created the earth in six days.

Although the Bible was the standard of Christian knowledge, one also wanted to experience the perfection of the world established by God through observation of nature, through 'reading in the book of nature'. The first medieval studies of nature were based on the traditional knowledge of antiquity. They were intended to demonstrate the omnipotence of God and remained valid until the early modern age. The scholars of natural history were now also anxious to determine the age of the earth. Their calculations were based on the information in the biblical scriptures, rather than on geological evidence.

The Jesuit priest Athanasius Kircher (1602-1680) was one of the most famous scholars of his time. In his work Die unterirdische Welt he speculated about the interior of the earth. According to his imagination, the body of the earth had bowels filled with water and fire. He was not interested in a theory of the origin of the earth, but in a description of the earth as a wonderful creation of God.

Insights into everyday life in mining in the 16th century are provided by the pictures of the Annaberg mountain altar, of which you can see a copy in the form of a tapestry. Since the late Middle Ages, silver mining has made the Erzgebirge one of the most flourishing mining regions in Europe. Annaberg-Buchholz also profited from this. After silver deposits were discovered in 1491, the village received its town charter in 1497 and the church was built. Both the village and the church were named after the patron saint of the miners, Saint Anna.

Alchemy was also concerned with stones. In early modern times, alchemists were convinced of the idea that there was an anima mundi, a world soul, which controlled all growth and transformation processes in nature. In their view, metals and other substances also had their own soul. All things in nature, they believed, always strive for perfection. They regarded the interior of the "living earth" as a kind of womb, a place of constant growth and development, in which metals and minerals mature. The alchemists asked about the properties of these and were especially interested in the preparation and transformation of simple metals into higher-valued ones, for example into gold. The alchemists also explored the importance of the stone world for the production of medicines. In order to be able to produce medicines from metals, minerals or substances extracted from them, alchemists such as the physician Paracelsus (1493/94-1541) developed special processes. Thus alchemy became the basis for later chemistry and pharmacy.

Here too, in the Francke Foundations, a pharmacy was founded around 1700 and medicines were produced, most of which were developed by the people themselves. Today, several handwritten collections of prescriptions provide us with insights into the recipes according to which the in-house orphanage medicines were produced. One exception is that of the professed alchemist Samuel Richter (born in the 2nd half of the 17th century, died after 1722, pseudonym: Sincerus Renatus). He did not belong to the personnel of the medicine expedition, but was demonstrably in contact with the Halle orphanage and exchanged ideas with them in the pharmaceutical-alchemistic field. In addition to recipes dealing with the Lapis Philosophorum, i.e. the philosopher's stone, he also mentioned numerous regulations for the 'improvement' of metals (their transformation into purer, nobler metals such as silver or gold).

In his work Natur-Kündigung Der Metallen, the economist and alchemist Johann Joachim Becher (1635-1682) discusses in detail, »[w]ie die Metallen gezeuget/ dann geboren/ und endlich aufferzogen werden.« The frontispiece of the volume gives an impression of the wealth and complexity of alchemical imagery:

In the crown of the tree, the alchemical symbols of the six metals gold, silver, mercury, copper, iron and tin are each located on a star-shaped background. The generation process of the seventh metal, lead, is symbolically represented. The one-legged man, who in alchemical imagery stands for the planet Saturn, to which the lead was assigned, lets a liquid fertilizing the earth flow out of a vessel with the symbol for lead (»ALO« = Latin for »I nourish«). The trunk of the tree bears the inscription »CONCIPIO« (»I receive«). On the crown of the tree the rays of the sun hit the tree, in which the word »GIGNO« is written (»I engender«). The bodies of heaven and earth, connected by the world soul, thus produce the metals which the miner (in the engraving on the right, leaning on a spade) can extract and process (»Elaboro« = I work) as soon as he has waited for their ripening process.

This section is about collecting stones which, like the objects from the other two 'realms of nature': flora and fauna, were an indispensable part of the art and natural history cabinets in the early modern period. Because they were 'inanimate' and not living beings, stones were considered the lowest form of natural phenomena. On the other hand, they were regarded as an initial state and thus as the basis of all animate nature. All other forms of existence were based on them, and in a certain way the stone remained contained in all higher forms of existence and beings of nature. This significance for the cosmos motivated the collecting of stones and their presentation in the natural history cabinets.

An example of the storage and presentation furniture for minerals of that time is the Mineral Cabinet in the Chamber of Art and Natural History of the Francke Foundations, which was built and furnished around 1740. Concealed by the doors is the serial number »1.A«. The cabinet is surrounded on the right by the cabinets »2.B« and »3.C«, which present plants, and on the left by »4.D« and »5.E«, which contain animals. Thus, given the numbering, one can see that the minerals were considered the beginning or the basis of the other phenomena in nature and are surrounded by these, the plants and animals. The cabinet is divided into three areas: at the bottom is the storage area with the drawers where the less spectacular pieces were kept. Above it is the presentation area with the glass doors for the more spectacular objects and above it is the artistic crowning painting that indicates the contents of the cabinet. From the collection catalog of 1742 we also know that the mineral collection was arranged according to the system of the Swedish biologist Carl von Linné. His system of arrangement for animals and plants is still in use today, but that for minerals did not prevail in the long run.

Gottlieb Friedrich Mylius (1675-1726) had studied law in Halle and Leipzig and worked as a lawyer in Leipzig. Probably also motivated by the collections in the Francke Foundations, he set up an important natural history cabinet and systematically collected minerals from the Saxon region. In his collection catalog of minerals, the so-called copper slate herrings of the Mansfeld region are also presented.

In the mines of the county of Mansfeld masses of well preserved fossilized fish were found in the copper slate. These were popular collector's items in the early modern period and often depicted in collection catalogs. Colloquially they were called copper shale herrings. The biological name of the now extinct bony fish is Palaeoniscum freieslebeni.

The two objects below come from other cabinets in the chamber, but are related to minerals and mining.

In 1850, the Hall geologist Christian Keferstein (1784-1866) donated his mineralogical collection to the Francke Foundations. It comprised more than 10,000 objects in 19 collection cabinets - the collection is now in the Institute of Geosciences and Geography at the Martin Luther University Halle-Wittenberg, the collection cabinets have been lost. It consisted of two parts, a mineralogical collection, which was arranged according to the system of the mineralogist Abraham Gottlob Werner (1749-1817), and a geological collection, whose order referred to the regions of origin of the pieces.

The relationship of the Pietists of Halle to geology was always connected with the theology of physics, which means »natural theology« and means that the Pietists encouraged natural and scientific studies in order to realize how perfect God had arranged the world. The aim was to link all natural physical phenomena with Christian doctrine. The knowledge about God's creation was now gained through observation, experiment and the acceptance of general laws of nature. Physicotheologists regarded the acquisition of knowledge of natural history as their God-given mission and a way of praising the Creator. At the center of this was the biblical Flood as a fundamental upheaval in the shape and life of the earth. The correct interpretation of the Flood and its consequences promised answers to questions about the origin of minerals, rocks and fossils.

The Flood also offered an explanation for the fossilized animals and plants that were found even on mountains and far away from any body of water. Originally, these fossils were not regarded as fossils but as games of nature (lat. lusi naturae). Also the presence of sediment layers above sea level, whose formation by water was already assumed at that time, could be explained in this way.

One problem of the theologically inspired research of that time, however, was that petrified plant and animal species were found that did not correspond to the plant or animal species of the present day. That these might be species that were extinct was unthinkable to the Pietists. According to their belief, God had completely arranged the world so that there could be no change of species or evolution. They accepted the assumption that these species did exist, but in distant regions of the earth and still undiscovered.

The thesis that these animals and plants exist in distant parts of the world, and that they had just not yet been discovered, was also advocated by the Querfurt theologian and deacon David Sigismund Büttner (1660-1719). In the environment of Halle's pietism, it was he who dealt most intensively with palaeontological phenomena. He corresponded with August Hermann Francke and sent him a large number of objects for the natural history cabinet of the orphanage. His main work on the »Deluge« was to serve »the natural knowledge of God and his creature«.

In Halle itself it was Johann Joachim Lange, the son of one of August Hermann Francke's closest confidants, who dealt with mineralogical-geological and mining issues. In 1723, he was offered a chair for mathematics at the University of Halle, but it is said that he was more interested in natural history. The first doctoral thesis on the geology of the region around Halle, which is exhibited here, was published in his environment. The author Johann Jakob Lerche was mainly interested in the economically useful resources in the soil.

Here, Johann Joachim Lange ties in with his own publications, thus demonstrating a usefulness thinking typical of Pietism: nature is arranged by God to be of use to man. For Lange, this leads to the requirement that man should explore nature from the aspect of usefulness and then exploit it. For this reason, Lange has given lectures on mining science at the university and has encouraged young people in publications to deal with questions of regional geology.

Lange also dealt with questions of mineralogical systematics. The trigger for this was the famous work Systema Naturae by the Swedish naturalist Carl von Linné (1707-1778) from 1735, in which he developed for the first time a uniform system of hierarchical order categories for all »Drey Reiche der Natur«. Johann Joachim Lange studied Linné's systematics very intensively and also taught it at the university. His probably best known and most influential work was the publication of the Systema Naturae in Latin and German, for many years the only German translation of this fundamental work.

This chapter is dedicated to the development of geology into a recognized science and is divided into two parts: While in the 18th century the Bible and Deluge theories were still at the forefront of the debate, »geognosy«, as it was then called, soon detached itself more and more from the traditional references to the Bible or combined it with new theories about the construction and development of the solid earth's crust. Pure speculative thinking was now replaced by empirical experience in the field, which had to be interpreted correctly.

Natural history, mining, alchemy, the passion for collecting and belief in creation: around 1750, geology began to develop as an independent natural science on this basis. This was already evident in the many theories of the 18th century, which speculated on the course of the earth's history and sometimes told of huge underground fires. In most cases, however, they focused on the biblical Deluge, the effects and mechanisms of which were passionately debated by nature-researching physicians, theologians and scholars, including world-famous universal geniuses such as Gottfried Wilhelm Leibniz, but also nature-researching professors such as the Hall physician Johann Gottlob Krüger (1715-1759).

In the second half of the 18th century, the typical methods of geology became established: minerals and rocks were determined on the basis of their sensual and chemical properties, rock layers were examined stratigraphically and the first geological maps were produced.

The two-part colored map of the Saxon Erzgebirge shows typical scenes from the mining industry, which has a tradition of over 800 years in this region and has shaped its economic and cultural development. The knowledge and techniques of mining in the Erzgebirge were trend-setting for geology on its way to science, especially in the German-speaking countries. After the Seven Years' War, mining experienced a real modernization push. Mining academies were founded to educate experts on a scientific basis in order to optimize the mining of raw materials for the economic well-being of the country. The famous mining academy in Freiberg, Saxony, was founded in 1765 and quickly became the center and international model of this development.

The figurehead of the Freiberg Academy was the mineralogist and mining inspector Abraham Gottlob Werner (1749-1817), whose finely crafted bust of Meissen porcelain watches over the volcanic objects here. He was undoubtedly the best known and most influential geologist of that time, attracting students from all over the world to the small mining town in the Electorate of Saxony. Among them were the Romantic Novalis (1772-1801), the explorer Alexander von Humboldt (1769-1859) and the geologist Leopold von Buch (1774-1853). Werner not only established geognosy, as geology was then called, as an empirically working empirical science of experience, but was also the main representative of Neptunism. The followers of this once popular theory of rock formation were convinced that almost all rocks were gradually formed in a primordial ocean and deposited when the water level fell, resulting in typical stratigraphic sequences over time. They had closely observed these in the Central German mountain landscapes. Active volcanoes, which were not to be seen there anyway, were considered by the Neptunists to be secondary phenomena, without any significance for the history of the earth. The older theory, however, represented by the volcanists, considered fire-breathing volcanoes to be the most important rock-forming force, even if they could only speculate about their function. After his death, Werner's Neptunistic theses quickly lost their importance, but his methods of geognosy shaped the research practice of the young geology well into the 19th century.

Around 1780, the question Did basalt come into being in water or in fire? sparked off a heated dispute between Neptunists and volcanists that lasted for many years and became famous as the basalt dispute, which we even encounter in Goethe's Faust. It can be regarded as the founding debate of modern geology in Germany, so to speak. In the end, victory was won by the volcanists, whose view finally became generally accepted in the early 19th century. For their research, among others in the Eifel and the French Auvergne, left little doubt that basalt could by no means be a child of water. Today we know that basalt is a volcanic rock that is formed when thin magma emerges from the earth's surface or from the ocean and cools down relatively quickly to form basalt lava. The oceanic crust consists mainly of basalt, but the fine-crystalline rock is also frequently found on the mainland, for example in the German low mountain ranges.

When lava cools down more slowly and contracts, tensions can arise in the rock. The shrinkage cracks that occur in this process run perpendicular to the cooling surfaces, resulting in the formation of polygonal - often hexagonal - prismatic columns. This columnar basalt can be found all over the world, in Germany for example in the Eifel, in the Erzgebirge or in Upper Lusatia, where this specimen also comes from.

Famous are the large basalt pillar areas in Northern Ireland and on the Scottish west coast, such as on the small island of Staffa. Scipione Breislak's (1750-1826) Atlas of Basalt Formations showed contemporaries the richness of the sometimes bizarre basalt landscapes of Europe and Mexico on high-quality copperplate engravings.

The volcanists attributed central importance to fire-breathing volcanoes and supposedly large underground fires for the formation of rocks, although they did not yet recognize the underlying principle of rising rock melts (magma).

Werner and his followers and opponents were still strongly oriented towards the idea of classical stratovolcanoes with large craters such as Etna or Vesuvius, which produced ash and lava flows and were always popular destinations for research and cavalry tours.

Initially, in the second half of the 18th century, research methods of geology had gradually developed, such as mineral and rock analysis, the study of rock layers in the terrain, the preparation of geological maps or the description of fossils. Now, around 1800, geology was in its heyday and developed into a veritable fashion science. Elaborate research trips and excursions often led to completely new insights and were indispensable for every geologist who thought highly of himself.

Many geologists of the early 19th century, known as catastrophists, believed that the earth had repeatedly been fundamentally changed by enormous natural disasters in the past. Some of them considered the biblical Flood to be the latest and for the time being last catastrophe that has shaped the present appearance of the earth. After 1830, the conviction prevailed that the earth had been undergoing constant change since its creation, which was unspectacular, extremely slow and often deep inside. Even if it cannot be observed directly, it is still able to bring forth and remove mountains - through periods of time beyond all imagination. The »Discovery of time« was one of the most important achievements on the way to modern geology.

The illustrations from the Agenda Geognostica show selected tools, devices and measuring instruments of early 19th century geology: geological compass with degree arc (12), degree arc with plumb line (13), simple clinometer (14), differential barometer (15), register thermometer according to James Six (16) and Daniel Rutherford (17). In addition to the obligatory hammer, the main tool of the geologist, the compass with degree bow and the barometer for measuring altitude were indispensable. The book also deals with the handling and practical suitability of the expensive and sensitive equipment and recommends reliable manufacturers. Good instruments, which facilitated the mapping work, were indispensable for the geologist. They provided more and more, and above all more accurate data to unlock the secrets of the rock world.

Ideal profile representations of the earth's crust, which became more and more popular in the course of the 19th century, were intended to clearly illustrate all essential geological conditions and processes at a glance. They reflect the state of knowledge at the time of their creation, but also the authors' individual views on the driving forces and principles of the earth's history.

Around 1800, geology developed into a veritable fashionable science that attracted both natural scientists and laymen, including the Haller jurist Christian Keferstein (1784-1866), to whom this chapter is dedicated. Even as a child he was enthusiastic about stones and started an extensive collection, which he later donated to the Francke Foundations. As an amateur geologist, he gained a certain reputation, among other things through his ambitious pioneering project of a geological map of all of Germany.

Johann Wolfgang von Goethe (1749-1832) assured in his letter that he would follow Keferstein's work on the geological maps with interest and that he would from time to time discuss it with the performing artists. In addition, he was confident that the map project would »not lack any good effects [...]«.

A few years after their meeting in Paris, Alexander von Humboldt (1769-1859) thanked Keferstein for a letter and the sending of »your so extremely instructive and important work«. He went on to write: »Since I had the pleasure of seeing you in Paris, you have not ceased to direct your activity toward the structures of Germany.« Humboldt promised to »contribute everywhere, to the best of my ability, to promote your work«. From his acquaintance with Humboldt, Keferstein had obviously not only promised to intercede with him in influential circles, but had also asked him to present copies of his works to the Prussian king and the crown prince. This »most kindly expressed wish«, however, »unfortunately does not allow my situation to be fulfilled directly, since iron laws of form [...] determine these broadcasts«. Keferstein was well aware and wanted to profit from the fact that Humboldt occasionally used his proximity to the Prussian royal house to support cultural and scientific concerns and to promote young talented artists and scientists.

The historical maps from the estate of the Halle geologist and mineralogist Christian Keferstein are now also available in the digital collections of the August Hermann Francke Study Center.

»Wir können also das Menschengeschlecht als eine Schar kühner, obwohl kleiner Riesen betrachten, die allmählich von den Bergen herabstiegen, die Erde zu unterjochen und das Klima mit ihrer schwachen Faust zu verändern. Wie weit sie es darin gebracht haben mögen, wird uns die Zukunft lehren.«

Johann Gottfried Herder (1744–1803)
Ideas on the philosophy of the history of mankind (1784–1791)

The exhibition ends with a leap in time to the present. It thus follows the annual theme of the Francke Foundations Berge versetzen. Über Tatkraft in Geschichte und Gegenwart. This motto is to be seen in a very positive light in view of the successful reconstruction of the foundations. In the context of this exhibition, we would like to reinterpret it, since mankind today is shaping and changing the earth in a way never seen before. At the latest since the beginning of the industrial revolution some 250 years ago, man has been intervening massively in the global ecosystem and influencing atmospheric, biological and geological processes to the benefit of his ever-growing needs. What has developed over millions of years can be irretrievably destroyed within a few generations. In view of the unimaginably long history of the earth, which was revealed in the 19th century, man was long considered an almost insignificant marginal phenomenon without much influence. Now he is once again moving right into the center of events. Therefore, not only geologists are discussing whether a new geological epoch of the earth has begun as a result of this profound human intervention: the Anthropocene - the age in which man fundamentally changed the earth. The final chapter of the exhibition is intended to provide food for thought.