and apparently he was close to Schelling, but his thought was independent. His contribution to the history of geochemistry is connected with the study of the chemistry of organisms. He was the first in the era of the new chemistry to suggest the importance of the chemistry of organisms, and in this respect he was far ahead of his time.
The roots of Reil’s aspirations and ideas go far back into the medical tradition. Beginning with the petrochemists of the seventeenth and eighteenth centuries, maybe even with Paracelsus (Bombast von Hohenheim, 1493–1541), the importance of chemistry in medical systems and in the understanding of healing the sick had never left the intellectual horizon of doctors. Generations of doctor-chemists follow one another incessantly for centuries. Reil considered the thorough, quantitative chemical study of organisms necessary, and he searched there for the answer to the manifestations of life. He was an innovator whose work was stopped by death at the very beginning. It is difficult to say what Reil’s contribution could have been, had his life been longer.
This was also the way of thinking of one of the most striking people of the first half of the nineteenth century: Alexander von Humboldt. In his early works, especially in “Flora Fribergensis Specimen” (1793), written before he plunged into South American nature, A. von Humboldt had come very close to many of the present-day problems of geochemistry. These studies of the young Humboldt were interrupted by his long journey, the processing of its results and the creation of the striking synthesis presented in his Cosmos. As an old man, in the fifth volume of Cosmos, he returned to one of the geochemical problems: the influence of life on its surroundings. But death stopped this work in the middle of a word.
In the paper of 1793 mentioned above, there was a brilliant effort to describe living organisms from the point of view of their chemical elements; being a mineralogist and a geologist, Humboldt never ceased seeking for their origins in the inert matter surrounding the plants. Decades passed until the problem was posed again as clearly as it had been by Humboldt. His way of putting forward the problem of the geographical spreading of organisms goes far beyond the limits of the studies of his followers; and deeper than the new branches of geography that appeared under its influence; it approaches the geochemical concepts of our days. He considered living matter to be an unbreakable and regular part of the planet’s surface, inseparable from its chemical environment.
During the entire nineteenth century, the field of contemporary geochemistry was being prepared. Step by step, the picture of the unity of the chemical composition of the Universe was becoming clear. This unity was first put on an experimental basis after the idea of the cosmic origin of meteorites penetrated the scientific mind. That idea was born in the first quarter of the nineteenth century, thanks largely to the continuous (1794–1826) scientific work of E. F. Chladni (1756–1827), an original scientist who, like Humboldt, stood apart from German university science. Chladni, who was not a chemist, followed his own path in life and was an innovator in science. The chemical composition of meteorites being identical to that of terrestrial bodies was first stated by E. C. Howard (1802), and at the same time J. L. de Bournon found out how they differ mineralogically. Both statements soon entered the scientific mind, but conclusions were drawn much later.
The notion that the chemical elements of living organisms were identical to those of inert matter was slowly acknowledged by science. Until the 1740s, it was not considered scientifically proven and was checked by special experiments. By the middle of the nineteenth century, following the methods brilliantly worked out by H. Davy, scientists had discovered the principal features of plant nutrition, which were then immediately taken up on a planetary scale (i.e., studied not only in their biological, but also in their geochemical aspects). This tradition has continued since the time of Lavoisier.
J. B. Dumas (1800–1884), J. Boussingault (1802–1887), K. Sprengel (1787–1859), J. von Liebig (1803–1873) and many researchers who followed them, or their contemporaries whose work was partly independent, stated the geochemical significance of green life. As we shall see, this life refers to the main part of the living matter of the biosphere. Dumas, Boussingault, and Liebig discovered the importance of green life in the gas exchange of the planet, and apparently it was Boussingault who had the deepest understanding of it, for he understood the geochemical aspect of the phenomenon best of all. He came across it outside the laboratories – in nature – during his long stay in the tropics and his studies of volcanic phenomena and minerals. In this field he was one of the shrewdest thinkers of the nineteenth century, and up till now we find in his works new material that has not been covered by scientific thought yet. Sprengel and Liebig furthermore discovered the real significance of the ashy elements. The theoretical constructions of Liebig influenced our understanding of these phenomena and completely reversed the explanation of the century-long characteristic of human culture – the importance of fertilizers for the productivity of soils. They also showed the geochemical role of green plants by using the compounds of phosphorus (this was clear to Boussingault too), potassium, and other elements needed by the plant.5
At the same time chemists did other studies on the minerals, waters, gases, and rocks surrounding us. Many scientists, especially chemists, considered mineralogy to be “the chemistry of the Earth’s crust,” as I. J. Bercelius called it. Gradually, precise research on the nature of minerals amassed an enormous amount of material. At the same time, by the end of the nineteenth century, the chemical analysis of rock formations, the research on waters, and the chemical study of fossil minerals gave a solid basis for empirical generalizations, for the creation of biochemistry.
Now we can see (it was remembered in 1931–1932) that different people understood the process being in progress quite clearly, and that the notion and the word “geochemistry” had already been created by that time. It was done in the 1830s and early 1840s by an original scientist from Basel – C. F. Schoenbein (1799–1868). His ideas were forgotten, but a historian of thought cannot forget the real influence of such an outstanding and brilliant personality as Schoenbein, who discovered ozone and worked in his own peculiar way. Schoenbein was not alone; he exerted a great influence on his surroundings. His articles and, as we can see now, his letters, are full of ideas and research that went beyond the limits of the science of his day; these were partly echoes of the past and partly anticipations of the future. Apparently, a friend of Schoenbein’s, M. Faraday (1771–1867), was not indifferent to his geochemical interests; his life was closely connected with that of Humphrey Davy whose significance for geochemistry I have already mentioned.
In 1842 Schoenbein wrote: “A few years ago I had already put forward the idea that we must have geochemistry before speaking about a real geological science that pays at least as much attention to the chemical nature of the matter comprising the Earth, and to their origin, as to the relative antiquity of these formations and the fossils of antediluvian plants and animals buried there. Of course, we can be sure that the geologists will at last cease to follow the trend they are supporting now. In order to broaden the limits of their science, they will have to look for new auxiliary means as soon as fossils fail to satisfy them. They will undoubtedly introduce mineralogy and chemistry into geology then. The time for this to happen does not seem to me very far from now….”6 Now these words seem prophetic to us. Schoenbein was mistaken regarding one point though: the time for his ideas came only in the twentieth century, decades after his death; then the word he had created was reborn and embodied by a new geological science.
By 1850, namely during the period of 1847–1849, brilliant and outstanding geochemical generalizations were published in scientific works that had collected an enormous amount of exact facts, which thereby entered general scientific thought and influenced it. This was done by three prominent naturalists who worked independently from each other, and whose works complement one another. None of them could cover the whole field of geochemistry by one synthesis but, as we see now, the results of their extended works which appeared almost simultaneously, presented a general outline for our new science. Nevertheless, their contemporaries did not see it – they noticed only contradictions and could not perceive them as part of one and the same whole.
These three naturalists were: Prof. K. Bischof (Bonn), who published
