THE SCIENTIFIC ACTIVITY OF BENJAMIN FRANKLIN*)

P. L. Kapitsa

From heaven he wrested lightning,
From tyrants—the scepter.

(Turgot on Franklin)

Franklin was born in America, in the city of Boston, in 1706. He died when he was 84 years old. His activity spans the entire eighteenth century and is closely connected with the rapid development then taking place in the natural and social sciences. This was the age of the “Enlighteners,” the age preceding the period of fundamental social upheavals in Europe.

Franklin’s name entered the history of world culture not only as the name of a major scientist, one of the founders of the theory of electricity, but also as the name of a major progressive statesman and public figure of America, who took the most active part in the struggle for its liberation from colonial status.

Contemporaries unanimously describe Franklin as an exceptionally charming man, broadly educated, with broad and humane views, an interesting and witty conversationalist. Franklin traveled often and lived abroad for many years, chiefly in England and France. There he had extensive contact with the leading people of his time and, toward the end of his life, became an extremely popular figure in Europe. In his homeland, America, Franklin remains to this day one of the most honored people in the entire history of the United States. Franklin’s varied activity and life have been well studied and are well known; many works have been devoted to him.

Franklin’s principal scientific discoveries in the field of electricity were made by him in the 1750s, before the work of Galvani and Volta, that is, before the epoch of galvanic current, and belong to the initial period of science’s conquest of this mighty force of nature.

*) A report read on January 17, 1956, at a ceremonial meeting of the Academy of Sciences of the USSR, the Soviet Peace Committee, Moscow State University named after M. V. Lomonosov, the Union of Writers of the USSR, and the All-Union Society for Cultural Relations with Foreign Countries, dedicated to the 250th anniversary of the birth of Benjamin Franklin.

In the 200 years that have passed since Franklin’s work, the science of electricity has advanced so far that today Franklin’s works are studied in secondary school, in those classes where pupils are only beginning to become acquainted with physics. All of us have known since youth the foundations of the doctrine of static electricity, although it is possible that some of us may have forgotten that, properly speaking, what was done here was done by Franklin. For example, does everyone remember that the names of the positive and negative poles were first introduced into science by Franklin?

A detailed description of Franklin’s scientific works is hardly of interest now, but the very history of the development of Franklin’s work in the field of electricity, it seems to me, is not only interesting but also useful for the modern scientist. This follows from the fact that the path of the development of science, i.e. the path of humanity’s cognition of nature, is a single one. In our search for scientific truths we often stray from the correct path, and then time is lost. Therefore, the less we deviate from the correct path, the more quickly and economically our knowledge and conquest of the forces of nature will develop. In studying the history of science, we find the factors that promote the rapid development of science. From this point of view, the history of the development of Franklin’s scientific work is of exceptional interest.

Franklin’s work on electricity was carried out by him over a short period of time: only 7 years, from 1747 to 1753. He first began to engage in scientific work when he was already 41 years old. By that time Franklin had already become a well-to-do man. The printing business, newspaper, famous almanac, and other printed publications he had founded in Philadelphia, then still a small city, enjoyed great success. Franklin began to engage in scientific work quite by chance, after he happened to attend a popular lecture with demonstrations on electricity. Such lectures were then widespread, since a number of electrical phenomena—such as the repulsion and attraction of electrified bodies, the electric spark, the unpleasant sensations caused by passing a discharge through a person—were then new and quite unusual, and served as excellent material for popular scientific lectures.

Shortly before Franklin attended lectures on electricity, the Leyden jar had been invented, which for the first time provided a method for condensing electricity in appreciable quantity. The possibility of performing experiments with a considerable reserve of electricity at once made demonstrations of electrical phenomena more vivid.

Franklin became very enthusiastic about experiments on electricity, and over the next 7 years he devoted a large part of his time to scientific work. These works at that time undoubtedly became leading in the devel—

THE SCIENTIFIC ACTIVITY OF BENJAMIN FRANKLIN

developing the doctrine of electricity and gained worldwide recognition. In this short period Franklin was recognized as the leading scientist of his time.

Most of the major scientific societies or academies acknowledged Franklin’s scientific merits by electing him a member, and a number of universities conferred upon him the honorary title of doctor.

Naturally, the question arises: how could it have happened that Franklin, who had never before engaged in physics, in a distant, small town in America, far from the centers of world science, already a man of mature age, was able in a few years of work to stand at the head of the development of an entire scientific discipline?

And this took place in the middle of the eighteenth century, when science was pursued by people at the level of knowledge of such scholars as Newton, Huygens, Euler. There can be no question of dilettantism here. How, then, could Franklin achieve results that remained inaccessible to professional scientists?

It seems to me that the explanation must be sought in the fact that Franklin was the first to understand correctly the essence of electrical phenomena and therefore opened the right path for further research in this field. An analogous sharp shift in the development of an entire, most important branch of physics—radioactivity—took place before the eyes of many of us.

After Becquerel discovered the phenomenon of radioactivity in 1896, in the course of a number of subsequent years an extremely rich body of experimental material accumulated on the study of physical phenomena connected with the radioactive property of matter. In all this diversity of experimental material there was no order, since the essence of the phenomenon of radioactivity itself had not been understood. Rutherford was the first to find that the physical phenomena connected with radioactivity are at once explained if one assumes that radioactivity is a process of the disintegration of matter. In order to see this, Rutherford did not need profound erudition; what was chiefly needed was his great imagination, insight, and boldness. At such initial stages in the development of science, the precision and punctuality characteristic of professional scientists may rather hinder the advancement of bold assumptions of this kind.

At the initial stage of the study of electricity it was necessary that such a bold step be taken. And Franklin took it.

Before Franklin’s work, a great deal of experimental material had already been accumulated, but the facts were scattered, and the hypothesis he put forward not only united these facts into a coherent picture, but also indicated the correct path for further research.

Franklin set forth his basic hypothesis in a letter to Peter Collinson in 1749. It gives a clear picture of the processes that occur when bodies are electrified. This picture remains essentially correct to this day.

Here is an excerpt from this letter: “Electric matter consists of particles that are extremely small, since they can permeate ordinary substances as dense as metal with such ease and freedom that they encounter no appreciable resistance.”

Today we call these “extremely small particles” electrons. Franklin further regarded every body as a sponge saturated with these particles of electricity. The electrification of bodies consists in the following: a body that has an excess of electric particles is positively charged; if a body has a deficiency of these particles, it is negatively charged. Franklin proved this quantitatively by means of a very vivid experiment.

Let us imagine that two people are standing on wax cushions, i.e., on insulators. One of them electrifies a glass rod by rubbing it. Then, if he touches the other person with it, both of them become electrified with respect to the earth, which is easily proved by the fact that either of them, on touching a grounded object, produces a spark. If, however, immediately after electrification the people standing on the insulators touch each other, a spark will pass between them; after this their electrification with respect to the earth will disappear. This is proved by the fact that, when they touch a grounded object, no spark appears any longer.

Franklin’s hypothesis proceeded from the material nature of electricity and explained these experiments in a simple way. If an insulated person touches another insulated person with a glass rod, one of them loses electric matter, while the other acquires it to the same extent. One of them is charged positively, the other negatively. If they touch each other, a discharge occurs and, since a constant quantity of electric matter is conserved, the former equilibrium is restored. Of course, Franklin at that time had no possibility of experimentally perceiving the material character of electricity and therefore had no way of determining who in fact receives electric matter and, consequently, is positively charged, and who loses it, i.e., is negatively charged. Therefore he assumed at random that electrified glass is positively charged, perhaps thinking that woolen matter, when rubbed against glass, rubs electricity into it. Only at the end of the last century, after the discovery of the particles of electricity—electrons—did it become known that it is not the positive electrode, as Franklin thought, that accumulates electric particles, but the negative one. In order not to change the customary designations of positive and negative polarity, the electron was assigned a negative charge.

I shall cite one more experiment of Franklin’s, which is also of great scientific interest.

Franklin extended the property of mutual repulsion of similarly charged bodies to charges located on metallic conductors. He believed that charges, repelling one another,

will tend toward the outer part of the electrified metallic body. He proved the validity of his supposition by the following experiment.

A metal teapot was placed on an insulator and electrified. It was necessary to find an experiment that would prove that the charge is distributed over the outer surface of the teapot. For this purpose a chain was placed inside the teapot, which could be gradually drawn out of the teapot by means of an insulated handle. The degree of electrification of the teapot was determined by the repulsion of two small balls suspended from it on threads. The experiment consisted in lifting the chain out of the teapot by the insulated handle and observing how, as it was drawn out, the degree of electrification of the teapot decreased.

Franklin reasoned as follows: while the chain is inside the teapot, its surface increases the inner surface of the teapot; when the chain is drawn outward, it increases the outer surface of the teapot. Franklin concludes: if the charge spreads only over the outer surface of an electrified conductor, then only when that surface is increased will the electrification decrease. This is in fact what is observed when the experiment is carried out.

I have cited these two experiments not only as brilliant in their simplicity, but also as the most fundamental in their results. Franklin gives a description of all his work in letters to his friend Collinson in England.

In these letters a larger number of various experiments is described, which have now become classical: the obtaining of an electric wind, the properties of the discharge of charges from a point, and others. In these same letters Franklin, from the standpoint of his hypothesis, gives a correct explanation of a number of already known electrical phenomena, for example the picture of the accumulation of electric charges in the Leyden jar, and on this basis he makes a flat capacitor. Collinson reported Franklin’s work to the Royal Society. Later he published it as a separate book, which became Franklin’s principal scientific work. This book went through a number of editions and was translated into many languages.

I shall not describe Franklin’s other experiments, but will mention only the experiments proving the electrical nature of lightning. These experiments became famous during Franklin’s lifetime and brought him the greatest renown. Although even before Franklin the hypothesis had been expressed that lightning and the discharge obtained from electricity produced by friction are one and the same phenomenon, though on different scales, no experimental proof of the correctness of this hypothesis had been found.

The clarity and correctness of Franklin’s understanding of the phenomena of electrification made it possible for him to find an experiment that for the first time convincingly proved the electrical nature of thunderstorm discharges. The idea of Franklin’s experiment was as follows.

Suppose that between a thundercloud and the earth there is placed a long vertical metal rod insulated from the earth.

If a thundercloud has an electric charge, then a charge of the opposite sign is induced in the upper part of the rod. If this upper end of the rod is made pointed, the induced charge will drain away and the rod will become charged with electricity of the same sign as the cloud.

Franklin believed that the presence of this charge could be detected by the spark that would arise if one touched the conductor with the free end of a grounded wire. Franklin assumed—as later became clear, mistakenly—that for this experiment to succeed the rod had to be placed on an elevation, so that it would be closer to the cloud. Since there was no such elevation near his house, he thought that he would not be able to carry out the experiment. He described in detail how it should be done, and proposed that others perform it. He himself decided to carry out an analogous experiment, but by a somewhat different method, one that did not require an elevation.

For this experiment, instead of a metal rod he decided to use a cord, raising it upward with a kite. Since during a thunderstorm there is always wind, the kite could be launched; and since rain is also falling, the cord, becoming wet, would become conducting and could replace the metal rod. To make it easier for the cord to become charged, provision was made for the induced charges to be able to drain away at the upper end of the cord. For this purpose Franklin placed points at the corners of the kite frame. In order to insulate the cord from the ground, a silk ribbon was tied to its lower end, protected from the rain. To the end of the cord near the ground a metal key was suspended, from which Franklin, during the thunderstorm, drew a spark. In this way, in the presence of his friends and acquaintances, he proved the electrical nature of the thunderstorm discharge. The kite experiment was carried out by Franklin on April 12, 1753; at the same time he first found that thunderclouds, as a rule, are negatively charged.

The French scientist Dalibard built, at Marly, an insulated rod exactly according to Franklin’s description, and on May 10, 1752, during a thunderstorm, electric sparks were obtained from it in the experiment for the first time; thereby, successfully—somewhat before Franklin himself, but by his method—the electrical nature of a thunderstorm was proved.

The technical details of both these experiments of Franklin and of others are very interesting, since they show his great experimental inventiveness. On becoming acquainted with the history of the development of Franklin’s work, one is struck by the speed with which Franklin’s views entered science. Despite the opposition of a number of prominent scientists, such as, for example, Abbé Nollet or Wilson, Franklin’s ideas in a very short time became firmly established in science. Of course, scientific truth is one and will always make its way into life, but whether this path is swift and more direct depends on people, not on truth.

In this respect Franklin’s activity can even now serve as an example of how, to use modern language, one must introduce one’s scientific achievements into practice.

Franklin strove to make each of his works at once the property of as wide a circle of people as possible. In Philadelphia, from among the local citizens, he organized a Philosophical Society; there he gave demonstrations and delivered lectures. Franklin often went abroad, where he communicated extensively with the scientific community. Franklin carried on an intensive scientific correspondence with a number of leading scholars in France, Italy, and England even at the time when America was at war with England. He independently learned French, Italian, and Spanish; he also knew Latin.

His ability to fight for new ideas manifested itself especially vividly when he had to introduce the lightning rod into life. But this will be discussed later. Let us now return to the question of the further development of Franklin’s work on electricity. In connection with Franklin’s ideas, scientists in many countries were engaged in experiments to study the nature of electricity. In our country, in Petersburg, Lomonosov and Richmann constructed rods for studying atmospheric electricity and called them a “thunder machine.”

Unfortunately, the works of Lomonosov—not only in the field of electricity but, more importantly, in chemistry, where he first discovered the law of conservation of matter—although they had fundamental significance, could not at that time exert such an influence on the development of world science as they undoubtedly deserved.

It seems to me that the chief reason here lies in the fact that the social conditions in which Lomonosov lived and worked did not give him the opportunity to communicate with scholars of other countries and to travel abroad. The isolation of the work of Lomonosov and Richmann undoubtedly also hindered the influence of Russian science on world science.

Especially sad was Richmann’s fate. In his works Richmann correctly indicated that the further development of Franklin’s experimental work should proceed along the path of finding a quantitative description of the phenomena of electrification.

Seeking a method for the quantitative measurement of the charge of the electrified rod of a thunder machine during a storm, Richmann, in order to make a quantitative reading, imprudently bent down and came too close to the conductor. He was killed on the spot by an electrical discharge to the head. This happened in 1753.

After Franklin’s works, the largest stage in the development of the science of electricity was the transition to a quantitative description of electrical phenomena. This was done by Coulomb, and only in 1785. It is well known how, with his torsion balance, he discovered his fundamental law of interaction of electric charges. Coulomb found that the force of interaction depends on the square of the distance between the charges.

The theoretical works of Gauss, Laplace, and Poisson that followed developed this basic law of nature into that coherent theory of the electrostatic field which we use so widely today. But in the history of the development of the doctrine of the electric field there is one comparatively little-known page that has a bearing on Franklin’s fundamental work and is worth recalling.

Almost 100 years after Coulomb’s work, in 1877, Maxwell published an article on the unpublished works of Henry Cavendish in the field of electricity. Maxwell, as the first director of the Cavendish Laboratory in Cambridge, built with funds provided by Cavendish’s descendants, had been given access to Henry Cavendish’s archive. In this archive he found a manuscript by Cavendish, fully ready for publication, experimentally proving the same inverse-square law of distance discovered by Coulomb. The experimental proofs in Cavendish’s experiment differed substantially from Coulomb’s experiment; the method was simpler and the proofs more precise than Coulomb’s. There was no date on Cavendish’s manuscript, but Maxwell assigned it in any case to years no later than 1775; consequently, it was at least 10 years before Coulomb’s discovery of the law.

In his work, Cavendish proceeded from the fact that one can theoretically show that on a hollow metallic conductor the entire electric charge can be distributed on the outer surface only if these charges repel one another according to the inverse-square law of distance. But experimental proof of the spread of charge over the outer surface of a conductor had already been given by Franklin with the experiment of the electrified teapot and chain, which I have already mentioned; it was only necessary to find a way to make this proof more exact.

Therefore Cavendish reproduced this experiment in a more perfect form. Instead of a teapot he took a hollow metallic sphere, and instead of a chain placed inside it, concentrically with it, a second metallic sphere. The two spheres could be either insulated or connected, depending on what was needed. Cavendish chose concentric spheres because this form of body made it possible to treat quantitatively the result obtained from the experiment. Cavendish’s experiment consisted in proving that the charge imparted to the outer sphere was distributed only over it and did not pass to the inner sphere.

Maxwell organized in Cambridge a repetition of Cavendish’s experiment, but with a more perfect measuring instrument, and showed that Coulomb’s inverse-square law is valid with an accuracy of almost one millionth, whereas by Coulomb’s torsion-balance method this law could be checked with an accuracy of only a little more than one percent.

Here the question arises: why, over the course of 100 years, did such first-rate scientists as Gauss, Poisson, Laplace, and others—the creators of the theory of the electric field—not notice that Franklin’s simple experiment with a kettle could already serve as experimental proof of the validity of one of the most basic laws of the electrostatic field—the law of Coulomb?

How could it have happened that Cavendish’s work remained unknown to everyone for 100 years? Maxwell, in his article, also points out that in this same work of Cavendish, ready for publication, in addition to Coulomb’s law, Ohm’s law had also been formulated and roughly verified. And this was done 70 years before that law was discovered by Ohm himself!

Naturally, one asks how it could have come about that so great a scientist as Cavendish, whom many called “the Newton of modern chemistry,” could neglect the publication of this work on electricity, which he, of course, could not but regard as fundamental.

History will hardly ever find an answer to this question, but the most probable explanation is that Cavendish simply forgot to send it to press.

At first this explanation seems incredible, since, it would seem, his fellow scientists should have known of these works and reminded him of them. But here a peculiarity of Cavendish’s character is revealed—he had neither friends nor comrades; in general he avoided people. A very wealthy man, the brother of the Duke of Devonshire, he lived an exceptionally secluded life, occupied only with his science. Even the servants of his household were forbidden to appear before his eyes in his rooms. His food was served on the table before he entered the dining room. Thus, because of this isolation from people, Cavendish’s scientific works—the fruits of his greatest scientific achievements, made in England—had no influence on the development of world science.

Much later, French scientists independently discovered these laws of nature. They passed their knowledge on to people, and these fundamental laws of nature rightly bear the names of Coulomb and Ohm.

Besides purely scientific works, Franklin has one more universally recognized achievement: his invention—the lightning rod. In the history of the introduction of this invention into life there is also much that is instructive. It is a long story; many research works have been devoted to it. Therefore I can only very briefly describe how Franklin invented and introduced the lightning rod.

I have already said that Franklin experimentally proved that lightning is nothing other than an electric spark passing between clouds and the earth when they have opposite electric charges. After the nature of the thunderstorm discharge had been revealed, the question naturally arose of how one could rationally combat

with the destruction and fires caused by lightning. It became clear that when lightning strikes a building, a ship, or any other elevated object, the harm is caused by the fact that a powerful electric current, passing through a poorly conducting medium, produces destruction and ignition. Therefore, if, when lightning strikes a building, the electric discharge is given the possibility of passing through a good conducting medium, such as metal, there will be no destruction. It became understandable why buildings with metal roofs and drainpipes were less subject to the effects of thunderstorm discharges. For example, the Temple of Solomon in Jerusalem was not once, in a thousand years, subjected to destruction by a thunderstorm, since it was covered with polished metal plates.

Naturally, after Franklin’s works, which revealed the nature of thunderstorm discharges, ideas at once began to appear among a number of people about the possibility of protection from lightning by diverting the electric discharge through well-conducting metal rods.

It is quite possible that a modest priest by the name of Prokop Diviš in a small town in Bohemia in 1754, proceeding independently from an understanding of the processes of electric discharges and using a grounded chain as a conductor for diverting the current, installed above the roof of his house a device closely resembling Franklin’s lightning rod. This undertaking ended sadly, since the townspeople, moved by superstitious fear, tore down and destroyed this device.

Undoubtedly, Franklin, with his sharp practical mind, saw earlier than anyone else the possibility of finding protection from lightning by diverting the current. But it was much more difficult for him to find the most rational form of the lightning rod and to compel public opinion to recognize it as an effective means of combating the destructions caused by thunderstorms. Franklin coped brilliantly with this task, and his activity in this direction may to this day serve as an example of how new technical ideas should be put into practice.

Franklin not only did not take out a patent on his lightning rod, but made it possible for anyone who wished to use it free of charge. Moreover, he conducted a large and skillful campaign of propaganda for introducing it into life. For lack of time, it is impossible to recount the full history of the introduction of the lightning rod; therefore I shall dwell on the most striking moments.

It is quite possible that no invention ever aroused such a storm of varied objections as did, 200 years ago, that small metal rod which in our day crowns almost every structure and is a standard element of its design.

Two hundred years ago the objections to the lightning rod were of the most varied kinds and arose on the most diverse grounds; there were also such argu—

ments: “lightning in the hands of Providence is an instrument of retribution, and therefore it is a sin to resist it.” Another, no less “convincing” argument was: “thunderstorms occur when evil spirits, demons, go out from under the obedience of the Almighty.” Therefore the only proper way to fight them was the ringing of bells, which drives away evil spirits. This is why for a long time it was considered necessary to ring the bells during a thunderstorm. Since, naturally, church bell towers are most vulnerable to lightning strikes, bell-ringing during a thunderstorm was not a safe occupation. Even after the invention of the lightning rod, for a long time they were not installed on churches, and the bells continued to be rung. In Germany, at the end of the eighteenth century, over 33 years 120 bell-ringers were killed by lightning and 400 bell towers were destroyed.

But Franklin’s chief struggle over the lightning rod was not centered on superstitious-religious objections, which held sway among the less cultured strata of the population. The struggle was with the very top of the society of that time. Both scientific and political objections arose against the lightning rod.

When Franklin described the action of the lightning rod, besides its obvious function of giving the electric current an unobstructed path along a metal rod into the earth, he also pointed to the possibility that another process might exist.

Franklin believed that if a thundercloud is above a structure and if the lightning rod is furnished with a point, then a slow leakage of electric charge can occur from it. We now call this phenomenon a silent discharge. It would neutralize the charge of the cloud and discharge it. Therefore Franklin admitted that the lightning rod not only protects a building, but in general can prevent lightning discharges. Franklin’s scientific opponents, for their part, believed that the leakage of charge from a point would not only fail to neutralize the charge of the cloud, but would create more favorable conditions for the occurrence of lightning. Therefore the lightning rod was more likely harmful, since it made possible the occurrence of lightning discharges that without it would not have occurred at all.

The scholars who held this point of view considered especially harmful and dangerous for a building its proximity to another building equipped with a lightning rod.

Public interest in these questions was very great, and this is well illustrated by the well-known case when, in Saint-Omer, in France, Monsieur de Vissery installed a lightning rod on his house; his neighbors were so frightened and indignant at this that they took him to court. The trial caused much commotion and lasted several years in the period between 1780 and 1784. It is interesting that the young lawyer Maximilien Robespierre spoke in defense of the lightning rod, and this celebrated case marked the beginning of his fame. It is also curious that one of the experts for the plaintiff was Marat, who considered the lightning rod a dangerous contrivance and was opposed to

his installation. After a long struggle and appeals, de Vissery won the case.

Franklin’s tactics throughout this struggle for the lightning rod are interesting. He usually did not speak publicly, but by means of conversations and by means of his enormous correspondence he continuously influenced leading scholars and public figures. Through such propaganda he created for himself a powerful army of the foremost people of the time, which fought for the implementation in life of his brainchild—the lightning rod.

In England the struggle against the lightning rod acquired a sharply political character. The English scholar Wilson tried to prove that the harmful action of the lightning rod could be avoided if its end were made blunt, thereby preventing the charge from draining away. Since the time of this dispute coincided with the epoch of America’s liberation from colonial status, and Franklin became a major political figure of young America and one of the most active fighters for freedom, every citizen of England who furnished his lightning rod with a point, rather than with a blunt end, was considered politically unreliable.

King George III of England demanded of the Royal Society, the English Academy of Sciences, that it renounce its decision in favor of a point on the Franklin lightning rod. To this demand of the king, the president of the Royal Society, Sir John Pringle, physician to the king and a personal friend of Franklin, gave the following well-known answer: “Both by his duty and by his inclinations he will, to the best of his ability, always carry out the wishes of His Majesty, but he is unable either to change the laws of nature or to alter the action of their forces.”

For these words he was dismissed from the post of royal physician and removed from the presidency of the Royal Society.

In the course of the struggle over the question of the lightning rod, all methods were used: slander, insinuations, both personally against Franklin and against his friends. Franklin maintained great calm, paying no attention to personal attacks, and invariably said that in questions of science truth is revealed only by experiment.

Indeed, experiment resolved this dispute, but many decades later, when the theory of gas discharges and of the electrostatic field had reached the modern level. We now know that this entire dispute had no foundation, since for an ordinary lightning rod it makes no difference whether it ends in a point or a blunt end. At a small distance from the ground, the geometrical form of the end of a lightning rod cannot noticeably influence the distribution of the electric field above the ground.

But one of the leading specialists in thunderstorm discharges, Dr. Schonland, points out that the process of neutralizing the charge of a cloud by means of the quiet discharge predicted by Franklin can nevertheless be carried out, but only when the point of the lightning rod is at such a great distance from the ground that it is comparable with the height of the cloud. This is the case for lightning rods placed on

THE SCIENTIFIC ACTIVITY OF BENJAMIN FRANKLIN

the tallest American skyscrapers; then it is indeed possible to observe from the point of the rod a quiet discharge that does not turn into lightning. Shonland adds that this, undoubtedly, would have given Franklin a feeling of just satisfaction, had he been able to know it.

Today the lightning rod is an integral part of all our structures, and, of course, it is impossible to calculate the number of buildings, structures, and ships that it will save from destruction or protect from fire. This merit is justly attributed to Franklin’s initiative.

I shall speak only briefly about Franklin’s activity in other fields of science, since, in addition to the famous achievements described, he also had achievements in other areas.

Franklin studied geophysics, produced a map of the Gulf Stream current, invented a musical instrument with rubbing glass spheres, an economical stove still widespread in America and France, street lamps, bifocal spectacles for senile farsightedness, and much else. In addition, thanks to his sociable character and lively mind, Franklin often consulted and promoted the development of science. Of course, information about most of these consultations has sunk into eternity, but some has come down to us.

Thus, for example, Louis XVI asked Franklin to be a member of a commission on the question of the value of the method of treatment proposed by Doctor Mesmer, who made use of so-called “animal magnetism.” It is interesting that the notorious Doctor Guillotin, inventor of the guillotine, took part in the same commission. Franklin denied the existence of animal magnetism, but considered it not a harmful method of treatment, since it entertains well-to-do people without causing them harm, which cannot always be said of other unfounded medicinal methods of treatment.

Franklin regarded the flights of the Montgolfier brothers very approvingly.

One must also note that sphere of Franklin’s activity which was connected with the opportunities for the development of world science that Franklin possessed as a major statesman of his time.

Franklin believed that scientific achievements are the property of all mankind, and that concern for the development of world science must stand outside political and military conflicts between peoples. Thus, during the war with England, when the famous explorer Captain Cook was returning from a voyage, Franklin gave instructions to all American ships and privateers to treat Captain Cook with respect wherever they might meet him during his journey. It is also of interest for our own day that Franklin, while sitting in Congress, persuaded it not to extend to scientific equipment the embargo imposed on all goods of English origin.

Studying Franklin’s biography, one comes to understand more and more why there exists universal respect and reverence for this great man, whom the people of America gave to humanity.

In an epoch of rapid growth in the natural sciences, every country produced its own great progenitor of science: for us it was Lomonosov; in England—Newton; in Italy—Galileo; in Holland—Huygens; in France—Descartes; in Germany—Leibniz; in America—Franklin. The achievements of these great scholars are the pride of all mankind.

And we, Soviet people, are grateful to the American people, who gave and brought up for humanity the great Franklin.