Makers of Electricity

by Brother Potamian; James J. Walsh

During a short stay that he made at Paris after his return, he sought the society of men of science as far as possible, and succeeded in getting in touch with all that was most promising in scientific progress at the time. He was already known rather favorably by many of the scientific men of the capital because of the paper on The Statics of Vaults, a monograph on static problems in architecture, which he presented to the Academy of Sciences in 1779. His next military assignment was to Rochefort. Here he composed his monograph on "The Theory of Simple Machines," which carried off the double prize that had been offered by the Academy of Sciences for the solution of problems connected with this important question. This attracted the attention not only of the scientific world, but also of his military superiors. As a result, he was sent successively to Cherburg and to the Isle of Aix, to direct engineering works, and accomplished the tasks involved with success.

Two years later, when he was about forty-five years of age, he was elected member of the Academy of Sciences by a unanimous vote. He was a man of great personal magnetism, and all those who came in contact with him learned to like him for his straightforward character and for the absolute righteousness of his life. Few men have made firmer friends than Coulomb, as few have ever shown more unselfish devotion to duty and to conscience than he, though under circumstances that were neither spectacular nor theatrical. It was harder to face the deadly climate of Martinique than it would have been to take one's place at the head of a forlorn hope in an outburst of enthusiastic courage; and Coulomb was to have other trials of quite as deterrent a nature, and was to meet them with the same imperturbed sense of duty.

Graft is sometimes supposed to be temptation peculiar only to our own times, but the opportunities for it have always been present in such work as Coulomb had to oversee, and the army engineer of all ages has had to stand or fall before it. It was proposed, about this time, to build a system of government canals in Brittany. Such a canal-system would, as is easy to understand, cost an enormous sum of money and give magnificent opportunities for speculation of various kinds. No small objection had been made to the project, on the score that it would not confer all the benefits on the region that were claimed for it, and Coulomb was commissioned by the Minister of Marine to determine the question of the advisability of constructing the canals, and of the probable effect which they would have on the commerce of the country.

After careful investigation, he came to the conclusion that the advantages which were expected to accrue from the project would not compensate for the enormous expense that would be entailed. This decision aroused the angry protest of a strong political faction, who expected to reap wealth and personal advantages of many kinds from the scheme, and who protested bitterly against Coulomb's report. He was able to support his conclusions in the matter, however, with such unanswerable mathematical and engineering arguments, that his opinion prevailed and the project was given up.

As a consequence, instead of the opportunity to serve a political party with every avenue to preferment and, above all, to wealth open for him, he found himself, for the time being, deprived even of the opportunity to devote himself further to his favorite occupations in military engineering. The excuse given for this interruption in his career, for there has always been an excuse for such action, was that proper representations for permission to make the report had not been made to the Minister of Marine; and instead of commendation, Coulomb received what was practically a reprimand.

Wounded by this injustice, which was manifestly due to the fact that his honest report had displeased those who expected to reap personal benefit from the canal project, and disgusted with a service in which such things were possible, Coulomb sent in his resignation. The Minister of Marine realized that the acceptance of the proffered resignation would surely expose the ministry at least to suspicion as to the reasons why Coulomb's report was not accepted with good grace. Permission to retire from the service was refused, as this would insure his silence. He was ordered back to Brittany to continue his work there, possibly with the idea that this unfavorable experience would be sufficient of itself to make him understand what was expected of him and render him a little more complacent to the wishes of those in authority. If any such ideas were entertained, they were destined to grievous disappointment. Coulomb was not of those who, seeing duty plainly, refuse to follow it because some personal advantage or disadvantage intervenes. Selfish reasons did not appeal to his character nor obscure the issues.

He went back to Brittany, ready to express his firm opinion in the matter and with integrity of soul untouched. The consequence was that the provincial authorities, recognizing their true interests, acknowledged the error they had come near falling into, and now wished to reward the engineer handsomely for his unswerving devotion to duty. Coulomb as promptly refused a reward for doing his duty as he had ignored even the appearance of a bribe to avoid it. Only after considerable pressure was he prevailed upon to accept the best timepiece they could procure, on which the arms of the province were engraved. It had what was quite rare in those days, a second's hand, and he constantly made use of this in all his experimental work thereafter. A French biographer says that, never was a souvenir better chosen nor more suitably employed. Coulomb's merits were recognized by the government authorities not long after, and he was made superintendent of the fountains of France. A few years later, he was promoted to the position of Curator of Plans and Relief Maps of the Military Staff of France, and was chosen as one of the commission of the French Academy of Sciences who went to England in order to study hospital conditions there. At this time, he was at the acme of his career. His grade was that of Lieutenant Colonel of Engineers, a position much higher in the foreign armies at that time than would be the post with the corresponding title in our army. He had been made a Chevalier of St. Louis, and it looked as though a brilliant future were opening out before him. Each year, for a decade, had seen the publication of one or more memoirs on important subjects, nearly every one of which contained some original material of the highest value, destined not only to add to Coulomb's reputation, but to furnish basic information for the further development of science.

In 1789, however, the Revolution broke out, and there was an end to all Coulomb's opportunities for work. He was utterly out of sympathy with the movement, the worst consequences of which he foresaw from the beginning, and he at once handed in his resignation of the various positions that he occupied under the government. He went into almost absolute retirement, devoting himself to the education of his children. During this time, however, he did not cease to cultivate science, inasmuch as he gave the finishing touch to various papers which he had previously outlined. Unfortunately, however, his departure from Paris made it impossible for him to continue his investigations in electricity for want of apparatus, and so there is a ten years' interruption in his life of scientific activity and of original work. Besides, it cannot be surprising that he should not have had the heart to go on with his work under the awful social conditions that prevailed. Many of his friends lost their lives during the stormy period of the Revolution; most of the others were banished or were in hiding. His beloved country had gone into an unfortunate eclipse, as he could not help but consider it; most of the nations of the earth were indeed in league against her, and the end was not yet in sight. It would be too much to expect of human nature that it should devote itself to abstruse problems in science at moments of such disturbance as this, and so some of the possibilities of Coulomb's original genius were lost to science during that calamitous period.

Like many of the great discoveries of science, Coulomb's most important work was done in the course of other investigations, and came by what might be called a happy accident. He had been investigating the qualities of wire of various kinds, especially with regard to their elasticity, so as to be able to determine the limits of their use in various engineering projects. When he discovered that the elasticity of torsion of a wire was a constant property, he proceeded to utilize it in the calculation of such delicate phenomena as those of electric and magnetic forces. The first instrument for this purpose that he constructed consisted simply of a long magnetized needle suspended horizontally by a fine wire. Supposing this needle to be at rest, if one moves it away from the magnetic meridian by a certain number of degrees, the twisted wire will have a definite tendency to untwist and to bring back the needle to its original position by a series of oscillations whose frequency can be readily observed.

For such observations, it is possible to obtain the value of the force acting on the needle and causing it to move to and fro at a given rate. This was the underlying idea which received very simple expression in the ingenious instrument which Coulomb devised and called a torsion-balance. With it, he set about determining the law which governs the mutual action of magnets and of electrified bodies with regard to distance, and found it to be the same as that which Newton found to hold for bodies distributed throughout the universe, that is, that attraction and repulsion vary inversely as the square of the distance. He also proved, with the aid of his torsion-balance, that the forces of attraction and repulsion vary as the product of the strength of the poles in one case and as the product of the electric charges in the other. These were the important discoveries of Coulomb's life; they served to earn for him the right to have his name given to the unit of electrical quantity, the coulomb.