In the twentieth century we are witnessing the flowering of this new kind of science of individual atoms in the form of atomic physics, radiology, radiochemistry, and most recently geochemistry – a small part of astrophysics. Geochemistry deals with the scientific study of chemical elements, i.e., the atoms of the Earth’s crust and the whole planet. It studies their history, their distribution and motion in space and time, and their ‘genetic’ correlations on our planet. It is distinctly different from mineralogy, which studies in the same time and space of Earth’s history only the history of atomic compounds, molecules, and crystals. In this strictly limited terrestrial planetary field, geochemistry discovers phenomena and laws whose existence we could only anticipate in the boundless fields of celestial space.
It is obvious to us now that the chemical elements are not distributed chaotically in conglomerates of matter in spaces such as nebulae, stars, planets, atomic clouds, and cosmic debris. Their distribution depends on the structure of their atoms. The atomic geometry of space and time, expressed by the history and distribution of atoms throughout the whole length and duration of the cosmos, exists in large and small forms, in the structure of both a cosmic nebula and a minute organism.2 The same laws regulate great celestial bodies and planetary systems, as well as the smallest molecules and maybe even the more restricted areas of the separate atoms.
More than two and a half centuries ago, the Dutchman, Christiaan Huygens3 (1629–1695) – one of the greatest scientists – discovered the inevitable identity of matter and the forces of the Universe, and the manifestations of life throughout its entirety. The identity of matter and forces was based on the gravity laws of his contemporary, I. Newton. It embraced also the Cartesian philosophy that reigned supreme in physicists’ minds and hindered the understanding of Newton’s scientific discoveries and generalizations of 1676 up until 1730–1740. In the seventeenth century, the notion of the unity of, speaking in modern terms, matter and energy throughout the entire cosmos, the whole of space and time, that had sometimes sprung up in the course of centuries, became part of the scientific understanding of the Universe. But Huygens was one of the few scientists who had clearly expressed the inevitable consequence of this notion: the cosmic unity of life we study in the biosphere.
One hundred fifty years after Huygens, the Englishman W. Hyggins, through scientific experiment and observation by spectrum analysis, proved the identity of chemical elements (atoms) of the stellar worlds based on terrestrial manifestations. The present-day creative explosion of ideas has not shattered this essential principle. He expressed it in the new concept of the identity of the basic elements (electrons, neutrons, protons, and the newly discovered positive electrons, or ‘positrons’), which make up atoms or chemical elements, and also in that of the genetic, though complicated connection existing between the atoms of different structures. Studying the laws and regularities of the history of elements of our planet, and studying the structure of the Earth’s atoms, we study at the same time the regularities of the smallest spaces and smallest moments that are indivisibly connected with the great whole of the cosmos. There are deep analogies between them and even more than just analogies.
Protons, electrons, positrons, photons, and quanta embrace the whole of time and space – all three aspects of the cosmos. They also constitute and embrace atoms. But chemical manifestations of atoms studied in geochemistry are only a small part of the phenomena connected with these main elements of the cosmos. The chemistry of the cosmos and geochemistry, or the atomic chemistry of the planet in space and time, is a small though important part of the reality studied by science. But we must remember and mention at once that the material substratum of space and time is not determined by chemical phenomena and the chemical characteristics of atoms.
2 forms of existence of chemical elements
Geochemistry, or the history of the chemical elements of our planet, could appear only after the new notions about the atomic and chemical elements had come into being. It could appear only recently, but it is rooted deeply in the history of science. Now we can see how the separate studies of different scientists of the past, which were not quite clear to their contemporaries, appear in a new form under the influence of the great scientific generalizations of the present – how they are receiving a new meaning and prove to be interconnected. Unfortunately, I cannot dwell upon the history of these ideas and upon the rise of geochemistry in detail. The preliminary work has not been done yet, and no full and coherent account can be given here of the way human thought has developed in this field.
No doubt, in the seventeenth century and earlier, systematic studies of geochemical problems were undertaken. A future historian of science will discover a fruitful scientific trend, list the names, trace a series of discoveries, observations and facts that are getting more and more precise, and find the roots of the most significant contemporary empirical generalizations and scientific ideas. This trend had become especially powerful and important by the end of the seventeenth century. Here I shall mention the name of the man who probably realized more of the scope and the importance of the phenomena encompassed by modern geochemistry than anybody else. This was Robert Boyle (1627–1691), a founder of the theory of chemical elements and a creator of modern chemistry.
The history of natural waters and of the world’s ocean in particular, the atmosphere as a weighty gaseous medium, the solution of gases in water, the first exact delineation of chemical elements in terrestrial bodies, and the beginning of precise chemical analysis of terrestrial products have all originated from Boyle’s works. I cannot, however, dwell upon these and other forgotten scientific studies, which have not actually passed unnoticed, and which have had a certain influence on the contemporary scientific mind. They lasted for almost two centuries. As early as in the second half of the eighteenth century, geochemical problems began to arouse scientific interest, although the idea of a chemical element was vague and far from the notions of the nineteenth and twentieth centuries.
G. F. Rouelle senior (1703–1770), and his even greater junior contemporary, L. Lavoisier (1743–1794), whose creative work was stopped while fully blossoming, had already posed these problems clearly enough. We cannot imagine the heights Lavoisier4 could have reached. Before his death he began to approach the deepest geochemical problems in his works concerning water and the physiology of breath [respiration]. Rouelle – the senior – published very little, but he influenced his contemporaries greatly by his public experimental lectures on chemistry that he delivered in Paris at the Royal Botanical Garden. All the intellectuals of Paris, or even of Europe, gathered for these lectures, and numerous foreigners who were in Paris – often great minds – attended these lectures. Nowadays it is very difficult to realize Rouelle’s influence; nobody has even tried to do it. But it is indubitably enormous, as it spread from Paris throughout Europe and survived his death. In the works of Lavoisier on the history of elementary gases and on the history of water, there are shining examples of geochemical generalizations expressed in the scientific language we are used to. Due to the great influence of Lavoisier’s ideas on the whole of modern chemistry, geochemical problems were introduced as well. Since then, some of these problems have begun to be included in chemistry courses.
His elder contemporary, Leclerc de Buffon (1707–1788), who was still very far from our present-day notion of chemical elements, presented in his history of minerals a series of brilliant and interesting generalizations and posed a series of significant geochemical problems. He was able to do this not only because he was a profound observer of nature who covered all the scientific knowledge of his time, but also because he lived in the midst of social activities and was an agronomist and a technologist. We find geochemical problems in his chapters on the history of native elements, and on that of metals in particular. But we find them also in other parts of his Les Epoques de la Nature (1780) and Histoire Naturelle, Générale et Particulière (1749 and following years). Not only was Buffon a great writer, he was also one of the greatest and most profound naturalists, one of the few people who had indeed observed the Universe as a whole. In these “Essays” we shall come across his ideas and their consequences more than once.
We cannot but mention also M. V. Lomonosov (1711–1765), another contemporary of Rouelle