Makers of Electricity

by Brother Potamian; James J. Walsh

Shortly after the beginning of the nineteenth century, Ampère, as one of his French biographers rather characteristically declares, redeemed whatever of mathematical sinning there might have been, in indulging in fond dalliance with the squaring of the circle, by a series of mathematical papers, each of which was in itself a distinct advance on previous knowledge, and at the same time, definite evidence of his mathematical ability. The first paper, published in 1801, was a contribution to solid geometry, bearing the title, "On Oblique Polyhedrons." His next paper, written in 1803, though not published until 1808, was a treatise on the advantages to be derived in the theory of curves from due consideration of the osculating parabola. Another treatise, written about the same time, had for title, "Investigations on the Application of the General Formulæ of the Calculus of Variations to Problems in Mechanics." This concerned problems which had interested and, in most cases, proved too hard of solution even for such men as Galileo, Jacques Bernoulli, Leibnitz, Huyghens and Jean Bernoulli. Arago's expression with regard to this work is: "The treatise of Ampère contains, in fact, new and very remarkable properties of the catenary (la chainette) and its development." He adds: "There is no small merit in discovering hiatuses in subjects explored by such men as Leibnitz, Huyghens and the two Bernoullis. I must not forget to add that the analysis of our associate unites elegance with simplicity."

It is not surprising, after such marks of mathematical genius, that Ampère was appointed to the chair of mathematics at the École Polytechnique, where he came to be looked upon as one of the most distinguished of French mathematicians. In 1813, he became a candidate for the position left vacant by the death of the famous Lagrange; and at this time, presented to the Academy general considerations on the integration of partial differential equations of the first and the second order. After his election to the Academy, Ampère continued to present important papers at its various sessions. Among these, three are especially noteworthy: one was a demonstration of Père Mariotte's law (known to English students as Boyle's law); another bore the title, "Demonstration of a new Theory from which can be deduced all the Laws of Refraction, ordinary and extraordinary"; a third was a memoir on the "Determination of the curved surfaces of Luminous Waves in a medium whose Elasticity differs in each of the three dimensions."

In his eulogy of Ampère, which, together with his article in the "Dictionnaire Universelle de Biographie," we have followed rather closely, Arago calls particular attention to the fact that in Paris, Ampère moved in two intellectual circles quite widely separated in their interests and sympathies. Among the first group, were the members of the old "Institute" and professors and examiners of the École Polytechnique and professors of the Collège de France. In the other, were the men whose names have since become widely known as students of psychology, of whom Cabanis may be taken as the representative. Ampère had as great a passion for psychology, and was as ready to devote himself to fathoming and analyzing the mysteries of the mind, as he was to work out a problem in advanced mathematics, or throw light on difficult questions in the physical sciences. These two sets of interests are seldom united in the same man, though occasionally they are found. At the end of the nineteenth century, we had the spectacle of very distinguished men of science in physics, and even in biology—Sir William Crookes, Sir Oliver Lodge, Professor Charles Richet, Professor Lombroso and even Mr. Alfred Russell Wallace—interested in psychic and spiritualistic manifestations of many kinds as well as in natural science; and, inasmuch as they did so, they would have found Ampère a brother spirit. Ampère indeed dived rather deeply into what would be called, somewhat slightingly, perhaps, in our generation, metaphysical speculation. At one time, he contemplated the publication of a book which was to be called "An Introduction to Philosophy." He had made elaborate theories with regard to many metaphysical questions, and had written articles on "The Theory of Relations," "The History of Existence," "Subjective and Objective Knowledge" and "Absolute Morality." Arago calls attention to the fact that Napoleon's famous anathema against ideology, far from discouraging Ampère, rather seemed to stimulate him in his studies, and he declared that it would surely contribute to the propagation of this kind of speculation, rather than to its suppression. It was simply another case of Napoleon overreaching himself, though this was in the domain of ideas and not in the realm of politics, where his fate was to reach him some time later.

How deeply interested Ampère became in metaphysics will perhaps be best appreciated from the fact that, for progress in metaphysics, exercise in disputation is needed, and had been the custom in the old medieval universities. Ampère once made an arrangement to travel from Paris to Lyons and stay there for some time, provided a definite promise was made that at least four afternoons a week should be devoted to discussions on ideology. The journey to Lyons, a distance of two hundred and fifty miles, was no easy undertaking in those days. The Paris, Lyons and Mediterranean Express now whirls one down to the capital of the silk district in a night; but in Ampère's time, it took many days, and the journey was by no means without inconveniences, which were likely to be so troublesome that a prolonged rest was needed after it was over. Ampère seems quite to have exhausted the interest of his friends in Lyons, who found his metaphysical speculations too high for them, though they themselves were specializing in the subject and would be glad to tempt him into discussions of the exact sciences; but in lyrical strain he apostrophizes psychological studies: "How can I abandon the country, the flowers and running waters for the arid streets of the city! How give up streams and groves for deserts scorched by the rays of a mathematical sun, which, diffusing over all surrounding objects the most brilliant light, withers and dries them down to the very roots! How much more agreeable to wander under flitting shades, where truth seems to flee before us to incite us to pursue, than walk in straight paths where the eye embraces all at a glance!"

Had Ampère been less successful as a mathematician or an investigator of physical science, these expressions would seem little short of ridiculous. As it is, they provide food for thought. Ampère seemed to realize that, for the intellectual man, the only satisfaction was not in successful research so much as in application of mind to what promised results. As in everything else, it was the chase, and not the capture, that counted. Seldom has this idea been applied to intellectual things with so much force as it seems to have appealed to Ampère, and one is reminded of Malebranche's famous expression, "If I had truth in my hand, I would be tempted to let it go for the pleasure of recapturing it."

The principal source of Ampère's fame, however, for future generations, was to be in his researches in the science of electro-dynamics. The name of this science will ever be inseparably linked with that of Ampère, its founder. It was for that reason, of course, that the International Congress of Electricians decided to give his name to the unit of current strength, so that it has now become a household word, and will continue so for ages to come. In spite of the resemblances, much more than superficial, between magnetism and electricity, the identification of these two with each other seemed as yet very distant. It is curiously interesting, however, to note that Ampère himself, in a program of his course, printed in 1802, announced that the "professor will demonstrate that electrical and magnetic phenomena must be attributed to two different fluids which act independently of each other." Ampère's fame was to be founded on the direct contradiction of this proposition, which he proposed and triumphantly defended by a marvelous series of experimental illustrations eighteen years later. In the meantime, the discovery of another distinguished scientist, doing his work many hundreds of miles away, was to prove the stimulus to Ampère's constructive imagination, so as to enable him to fill out many obscure points of knowledge with regard to magnetism and electricity.

This suggestive discovery was that of Oersted, the sketch of whose life and work immediately precedes this. Oersted demonstrated that a current of electricity will affect a magnetic needle. This epoch-making discovery reached Paris by way of Switzerland. The experiment was repeated before the French Academy of Sciences by a member of the Academy of Geneva, on September 11th, 1820. The date has some importance in the history of science, for just seven days later, on the 18th of September, Ampère presented, at the session of the Academy of Sciences, a still more important fact, to which he had been led by the consideration of Oersted's discovery while testing it by way of control experiment. This brilliant discovery of Ampère, Arago summed up in these words: "Two parallel conducting wires attract each other when the current traverses them in the same direction. On the contrary, they repel each other when the current flows in opposite directions. The phenomenon described by Oersted was called, very appropriately, electromagnetic, whilst the phenomena described by Ampère, in which the magnet played no part, received at his suggestion the general name of electro-dynamics, which has since been applied to them."

At first it was said that these phenomena were nothing more than manifestations of the ordinary attractive and repelling power of the two forms of electricity which had been so carefully studied, especially in France, during the eighteenth century. Ampère at once disposed of any such idea as this, however, by pointing out that bodies similarly electrified repel each other, whilst those that are in opposite electrical states attract each other. In the case of conductors conveying currents, there is attraction when these are in the same direction, and repulsion when they flow in the opposite direction. This reasoning absolutely precluded all possibility of further doubt in the matter, and this particular form of objection to Ampère's discoveries was dropped at once.

Having satisfactorily disposed of other objections, Ampère was content neither to rest quietly in his discovery nor merely to develop various experimental phases of it which would be extremely interesting and popularly attractive, but which at the same time might mean very little for science. With his mathematical mind, Ampère resolved to work out a mathematical theory which would embrace not only all the phenomena of magnetism then known, but also the complete theory of the science of electro-dynamics. Needless to say, such a problem was extremely difficult. Arago has compared it to Newton's solution of the problem of gravitation by mathematics. Considering the comparatively small amount of data that Ampère had at his command, this problem might very well be compared to that which Leverrier took up with so much success, when he set about discovering by calculation only the planet Neptune, as yet unknown, which was disturbing the movements of Uranus.

It might be thought that these discoveries of Ampère would be welcomed with great enthusiasm. As a matter of fact, however, new discoveries that are really novel always have, as almost their surest index, the fact that contemporaries refuse to accept them. The more versed a man is in the science in which the discovery comes, the more likely is he to delay his acceptance of the novelty. This is not so surprising, since, as a rule, new discoveries are nearly always very simple expressions of great truths that seem obvious once they are accepted, yet have never been thought of. They mean, therefore, that men who consider themselves distinguished in a particular science have missed some easily discoverable phenomenon or its full significance, and so, to accept a new discovery in their department of learning men must confess their own lack of foresight.