F. U. T. Aepinus. Theory of Electricity and Magnetism. Edited and annotated by Professor Ya. G. Dorfman. Publishing House of the Academy of Sciences of the USSR. Series “Classics of Science,” 1951, 564 pp. Price 26 rubles 50 kopecks.

In the middle of the eighteenth century the Petersburg Academy of Sciences was in the second quarter-century of its existence. Despite so young an age—and perhaps precisely because of it—within what was then the only scientific institution of the country, the most current problems of the time were posed and resolved, among which questions of electricity occupied one of the most prominent places.

Being considerably younger than the Royal Society of London or the Paris Academy of Sciences, the Petersburg Academy did not display the routine and rigidity from which the named scientific corporations were not free. Characteristic in this respect was the attitude of prominent English and French scholars toward the then-new theory of the electrical nature of thunderstorm discharges. Benjamin Franklin writes in his memoirs that when his first letter was announced at a meeting of the Royal Society (it had been addressed to a member of the Royal Society, P. Collinson), containing a description of experiments set up and conclusions to which the investigator had come, the latter was met with laughter, and Collinson was refused publication of his correspondent’s memoir in the Philosophical Transactions. The same fate befell another member of the Royal Society, Mitchel, to whom Franklin had also sent his work. This is what he writes: “One article on the similarity of lightning with electricity I sent to an acquaintance of mine, also a member of the Royal Society, Mitchel. In his reply letter he informed me that the article had been read, but had provoked the laughter of the connoisseurs”*). It was still worse in France. Translated into French at the initiative of the famous natural scientist Buffon, Franklin’s work aroused a storm of indignation. The new ideas were so alien to established conceptions, of which the most vivid exponent was the then-famous French physicist, Academician Nollet, that the latter considered, as Franklin writes, that there was no American Franklin in the world at all, that all this had been staged by Nollet’s enemies in order to shake his influence. And even after Nollet became convinced that Franklin was a real, existing investigator and was continuously conducting his researches, the French scholar nevertheless issued a series of open letters to Franklin, “refuting” his views.

All this occurred in the 1750s of the century before last, while ten years earlier, in 1743, M. V. Lomonosov, in the “Ode on the Northern Lights,” expressed a thought testifying that already then, when Franklin had not yet thought about electricity**), the Russian scholar had a definite

) Benjamin Franklin’s own story.* University Pensilvania Press. Philadelphia, 1937, p. 164.

**) Franklin’s chance acquaintance with the field of electricity dates from 1746, when, having come to his relatives in Boston, he saw how a certain Spence, a doctor who had come from Scotland, demonstrated electrical experiments to the assembled public, but did this very ineptly, “since he did not possess sufficient knowledge.” This prompted Franklin, as he writes, upon returning to Philadelphia, to take up the repetition of the experiments.

notions about atmospheric electricity. In 1744, systematic research in the field of electricity was already being conducted at the Petersburg Academy. It was pursued by G. V. Richmann and M. V. Lomonosov; their investigations differed markedly from what was then being done abroad. Ya. G. Dorfman rightly notes: “While in Western Europe investigations of electricity had been carried on since the end of the sixteenth century, in Russia experimental investigations of electricity were begun by G. V. Richmann and M. V. Lomonosov in 1744. And, despite the fact that Russia entered this field of science a century and a half later than Western Europe, the studies of Richmann and Lomonosov were, from their very first steps, conducted on a higher scientific level than those of their foreign contemporaries. From the very beginning Russian physicists set themselves the task of quantitative measurements of ‘electric force.’ This is attested by Richmann’s own notes that have come down to us, on the basis of which the young adjunct M. V. Lomonosov composed a memorandum entitled ‘Electrical Experiments Most Worthy of Note’” (p. 469).

At the height of his work on electricity Richmann died (1753), struck by lightning. For several years the post he had occupied remained vacant. The Academy long searched for a worthy successor and in 1757 invited Aepinus to this post. Presenting his candidacy to the president for approval, the Academy wrote in its report: “And he has a sufficient reputation in the learned world, and Mr. Euler praises his art, although he has not proposed him and does not wish to let him go), and likewise Messrs. Kotelnikov and Rumovsky give very good testimony of him; the post of professor*) of physics, however, after the death of Professor Richmann, is still vacant, and no worthy aspirants have been found.”

Like many outstanding scholars who came to Russia, Aepinus found here his new homeland, hospitably received him and provided broad opportunities for scientific creativity. Aepinus’s activity proceeded not only in the field of science. Five years after moving to Petersburg he was appointed director for the educational section of the Land Gentry Cadet Corps, and in 1765 Catherine II “deigned to enroll him among the teachers of the heir, the future emperor Paul I.” Aepinus was given assignments in the “Foreign Collegium” (p. 464). He showed himself especially in the field of public education. To his pen belongs the “Memoir on the Organization in Russia of Lower and Secondary Education.” Aepinus spent more than forty years in service in Russia. In 1798, at the age of seventy-four, he retired, settled in Dorpat (Tartu), where he died in 1802.

Aepinus had been concerned with questions of electricity even before moving to Russia, but he wrote his first significant work in this field in Russia. On September 7, 1758, he spoke at a ceremonial meeting (“assemblée”) with a report (“public act”): “Discourse on the similarity of electric force and magnetic force.” The report was published in Russian, Latin, and German.

At the annual meetings, as a rule, reports were presented on the most important scientific themes, especially those stirring the scientific world. Let us recall that five years earlier Lomonosov had spoken at such a meeting with the celebrated “Discourse on Air Phenomena Arising from Electric Force and Concerning the Origin of Northern Lights.”

*) Before coming to Russia, Aepinus was a member of the Berlin Academy, headed by L. Euler; the latter did not cease his service in the Petersburg Academy of Sciences, where his scholarly activity had begun and where he returned after his departure from Russia sixteen years earlier (1833).

**) In the eighteenth century the full members of the Academy were called professors.

“proceeding.” It was then recognized that the theory of electricity was the most urgent task, and, on Lomonosov’s initiative, a competition was announced for the solution of the problem: “To discover the true cause of the Electric force and to give its exact theory.” Lomonosov himself drew up the program for this problem, appended to his published “Word”*). Essays were submitted to the competition—as dissertations were called in the scholarly writings of the eighteenth century—from all parts of the world; Euler’s treatise received the prize in the hundred chervontsy. But the “true cause of the electric force” was not found, and the “exact theory” that would have explained all the accumulated data was not given. The ever-increasing discoveries, following one after another, complicated this field of natural science, putting forward ever newer and newer problems.

One of the most difficult questions was that of the connection between electrical and magnetic phenomena. It was finally solved in the 1820s–1830s, after the discovery of the magnetic field of an electric current and after Faraday, through the discovery of electromagnetic induction, succeeded in turning the phenomenon observed by Oersted back upon itself. These discoveries served as the scientific foundation on which modern electrical engineering arose; its beginning dates to the middle of the nineteenth century.

But a century before that, in the 1750s, it was clear to the most farsighted investigators that the study of electrical and magnetic phenomena and their interrelations concealed within itself great possibilities. The Petersburg Academy of Sciences, having designated this topic for a report at its annual meeting, showed the whole world what great importance it attached to this problem. It must be borne in mind that for a century and a half, since the time of W. Gilbert, the opinion had been firmly established that there was nothing in common between electricity and magnetism. The very topic, in the eyes of eighteenth-century physicists who adhered to the old ways, might have seemed, as Ya. G. Dorfman justly notes, paradoxical (p. 489). But progressive scholars never hesitated to raise their hand against what was old and obsolete; Epinus undoubtedly belonged to such scholars. In his speech he noted: “The boldness with which I set myself up in the present condition, perhaps, may appear to you, most honored listeners, reprehensible.” Experiments and observations confirmed him in the propositions he advanced. “One must think,” he wrote, “that nature is in some way either envious in her mysteries, or loves to sharpen the human mind and test its diligence: for she hides so carefully the phenomena appearing in the works of art that they can never be seen at first glance, but only after countless trials does she allow the knowledge of her mysteries. In the same manner nature acts as well, and usually follows her own way in considering the similarity of the electric and magnetic force. For from the very beginning the visible and always simple phenomena of both have such a resemblance to each other that one might think of the similarity of the causes of the magnetic and electric force; and was it not by the skill of the investigators of nature that through countless studies of the magnetic and electric force this mystery could be fully known? The more difficult it is, the more gratifying it will be, as is usual in human affairs, when we can discern the perfect similarity between both forces” (p. 391).

By the time Epinus delivered his speech, he had for a long time been working on the question that interested him, and the results he obtained, which he reported at the ceremonial meeting, allowed him to say in conclusion: “I have shown, and now, most honored listeners, I have shown the likeness between the electric and the magnetic force, and in this way I have fulfilled my intention” (p. 414).

*) Works of M. V. Lomonosov, vol. IV, St. Petersburg, 1898, pp. 348–351.

The author, however, did not limit himself to having discovered the most important facts. This was not his ultimate aim. “Before concluding,” Aepinus emphasized, “it remains for us to point to a most useful application which natural philosophy shows us” (ibid.).

Of course, in the eighteenth century, on the narrow basis of electrostatics, there was exceedingly little “most useful application” of the achievements of the doctrine of electricity. Before the discovery of the electric current and the invention of the powerful, namely electromagnetic, generator, electrical engineering was impossible. But even in those distant times the country’s highest scientific institution creatively shaped thought, directing it along the path indicated by Lomonosov in the aforesaid “Discourse on Air Phenomena Originating from the Electrical Force.”

If, in practical terms, researchers were bound by the imperfect state of the doctrine of electricity, then in the proper scientific sense the new step made in the Petersburg Academy of Sciences had enormous consequences. The “Speech on the Similarity of the Electric Force with the Magnetic” was, as it were, Aepinus’s preliminary communication; it was followed by the large treatise published in 1759: An Essay on the Theory of Electricity and Magnetism with an Appendix of Two Dissertations, of Which the First Explains Certain Electrical Phenomena, and the Second Certain Magnetic Phenomena.

In the history of science this treatise is recognized as fundamental for the theoretical investigation of electricity and magnetism. Aepinus’s treatise was printed in Latin and has not been republished since then. It appears here for the first time in a modern European language. Aepinus was one of the first scholar-electricians whose investigations were based not only on experiments and observations but also on mathematical calculations. Unlike those authors who, carried away by the formal mathematical method, defended the so-called theory of action at a distance, Aepinus did not share these views. Ya. G. Dorfman was the first in the literature to point to the erroneousness of the assertion by certain historians of science who attributed to Aepinus incorrect views known under the name of the theory of actio in distans.

More than a quarter of a century before Coulomb, Aepinus advanced propositions that underlie the law named after the French scientist. Aepinus states explicitly that the force of interaction of electric charges decreases inversely proportional to the square of the distance. It is generally known that the discovery of the phenomenon of electrostatic induction belongs to Aepinus. His name is also associated with the discovery of the electrostatic polarization of dielectrics.

The Leyden jar (an electrical condenser), discovered in the 1740s, was the subject of study by the most eminent scientists of the time, including Franklin. But Aepinus was the first to give a complete explanation of the Leyden jar, pointing out certain errors made by the American investigator. In Aepinus’s treatise there are passages testifying that, a hundred years before Federsen, the Russian academician expressed the idea of the oscillatory character of the discharge of the Leyden jar.

Aepinus’s treatise also contains purely magnetic investigations. On the basis of painstaking mathematical calculations, the author developed methods, excellent for that time, for magnetizing magnetic needles. Aepinus devoted much attention to terrestrial magnetism and asserted that the terrestrial globe possesses a magnetic core. Using the mathematical method, he was the first to calculate how a magnetic needle would behave in the earth’s magnetic field. In Aepinus’s treatise there are discussions of the origin of deposits of magnetic iron ore. In this one cannot fail to see the influence of Lomonosov’s well-known work “On the Birth of Metals from the Shaking of the Earth.”

The editor of the edition under review faced a number of difficulties. Above all, he had to establish the date when this remarkable scientific monument appeared, since Aepinus’s book was printed without an indication of the year of its publication. Ya. G. Dorfman, having carefully studied the treatise,

showed, relying chiefly on studies of the introductory part, that Epinus’s work was written in 1758 and published in the following year, 1759.

The editor’s and commentator’s chief task was to show how closely this publication of the Academy of Sciences was connected with all its activity, and what the role and significance of Epinus’s work were in the history of the teaching on electricity and in the history of physics in general. Ya. G. Dorfman carried out this task at a high scholarly level, with the deep knowledge of eighteenth-century science characteristic of him and with an understanding of its strengths and weaknesses.

Ya. G. Dorfman’s article “Epinus and His Treatise on the Theory of Electricity and Magnetism” occupies a considerable place in the published edition (pp. 461–538). An entire section of this article is devoted to the state of the science of electricity and magnetism in the 1740s–1750s and to the significance of the investigations in this field carried out by Academician Richmann and Lomonosov. At first glance this section may seem too extensive. But one must take into account the circumstance that this is one of the most glorious pages in the history of Russian science, and that it has been developed quite insufficiently. In view of the fact that the “Classics of Science” series is used by teachers and students in higher educational institutions, it must serve as an aid in the study of the history of science. In this respect the editor’s article can be used as an extremely valuable aid. Whereas Lomonosov’s works on electricity have been the object of study for more than a century, the works of Richmann have been scarcely touched by historians of science, and some of his works—very valuable ones, as Ya. G. Dorfman has shown—have been entirely forgotten. In Ya. G. Dorfman’s exposition these works serve as a vivid background for the further development of the doctrine of electricity, in the history of which Epinus’s works played such an important role.

Among the most difficult questions that the commentator had to clarify is the question of the relation of Franklin’s works to Epinus’s creative activity. The point is that Epinus adhered to the unitary Franklinian theory and did not conceal the colors in which he gave due credit to its author. Therefore, in the history of science Epinus was considered one of those investigators who contributed to the magnification of Franklin’s fame. Having studied in detail the works of both scholars, Ya. G. Dorfman arrived at conclusions differing from the traditional assertions of historians of physics: “Epinus—writes he—based his work on Franklin’s unitary theory. He did this not at all out of any special reverence for Franklin. On the contrary, Epinus critically examines every argument of Franklin’s and very sharply notes his errors and inconsistencies in his conclusions. But, in seeking to construct a quantitative theory of electricity and magnetism, Epinus obviously decided to base it on the simplest premises, so as not to complicate the calculations. The theory of one electrical fluid proposed by Franklin made it possible to approach the mathematical treatment of phenomena much more simply than the theory of two electricities, i.e., of two kinds of charge carriers. Therefore, without binding himself by the approval of Franklin’s views in all their details, Epinus borrowed from his theory only the most general propositions” (pp. 492–493).

The originality and fruitfulness of Epinus’s ideas were recognized by all the outstanding scholars of the eighteenth and nineteenth centuries who became famous for their work in the field of electricity. Ya. G. Dorfman cites detailed statements by such authorities as Volta, Saussure, Cavendish, Coulomb, Faraday, and many others, who acknowledged that the works of the Russian academician in a number of cases had a decisive influence on them. By a large number of facts Ya. G. Dorfman confirmed his assertion about the exceptionally important significance of Russian science in the history of the doctrine of electricity. His conclusion is entirely logical: “It is no accident that Russian

Bibliography

physics of the eighteenth century, which brought Lomonosov and Richmann into its orbit, as well as Aepinus. Between the experimental investigations of Lomonosov and Richmann, on the one hand, and the theoretical works of Aepinus, on the other, despite all the differences in their scientific views and methods, there exists a definite historical connection. Aepinus’s treatise, which initiated quantitative calculations in the theory of electricity and magnetism, was a historically inevitable step after the works of Richmann and Lomonosov, which laid the foundation for quantitative experimental investigations of electrical phenomena. Thus, “the introduction of a quantitative interpretation of phenomena into the science of electricity and magnetism represents an outstanding achievement of the Petersburg physicists of the eighteenth century” (p. 537).

A valuable supplement to Ya. G. Dorfman’s article is provided by the notes placed at the end of the book.

M. Radovsky