Nothing more was done for the next twenty-five years to enlarge the knowledge of the phenomena of electricity. It stood, in fact, on a footing not very far advanced from what it had been two thousand years before. The achievements mainly consisted in a great number of entertaining experiments performed for the delectation of great and little children. Various machines had been made for exciting electricity, but they served only, or at least chiefly, for amusement, allowing ladies to fire off a cannon by a touch of their delicate hand, and bringing ladies and gentlemen together to behold the wonderful spectacle of an infant’s hair being made to stand on end, the little creature having been placed upon cakes of resin, and fastened to the ceiling by silken cords. The whole was little more than a repetition, on a greater scale and with improved means, of the ancient Greek experiment of rubbing a piece of amber on the sleeve of a philosopher’s coat.
The first great step towards a practical insight into the nature and phenomena of electricity, hitherto a mere plaything, was made in the year 1745 in the ancient Dutch city and university of Leyden. Two professors of the high school, John Nicholas Allamand, a member of the Royal Society of London, and Peter Van Musschenbroek, author of a treatise entitled ‘Introductio ad philosophiam naturalem,’ had been trying, like many other scientific men of the time, electrical experiments, when the thought occurred to them that the real reason why all the work of the same kind had as yet produced such slight results was that the electrical force was absolutely unstable. It slipped, so to speak, through their hands, before they could look at it; it vanished ‘like a dream, leaving no substance behind.’ One body, they knew, had the power of electrifying another, but only to let the mysterious force pass on, like a current of water running down a cataract. Could they but ‘bottle up’ electricity, what a grand gain would this be to science! So thought the two professors of Leyden university; and thought justly. They went on experimenting, with this end in view, till at last so-called ‘accident,’ the mother of millions of human inventions and discoveries, threw a brilliant light on the dark road along which they were groping their way.
One day Professor Allamand and Van Musschenbroek, together with a pupil named Cuneus—a sort of Wagner, it would seem, sitting at the feet of Dr. Faust—were trying the effects of electricity on a small iron cannon, suspended by silk threads, and connected by a wire with a glass bottle half full of water, when whey were startled by an extraordinary incident. Curious, like all students of occult sciences, young Cuneus took it into his head to see what would happen if he held the prime conductor of the electrical machine in one hand and the electrified bottle of water in the other. Something wonderful happened, indeed, causing profound amazement and terror to the three persons witnessing it, most of all to the immediate experimenter, who sank down on the floor, half dead with fright. Master Cuneus had received an electric shock. It was the first electric shock ever administered by artificial means to any human being.
Such was the origin of the long-famous ‘Leyden jar,’ or, as it was originally called, ‘Leyden phial.’ The whole of the scientific world of Europe was as much startled by the discovery that electricity could be imprisoned, like Ariel in an oak-tree, as the two Leyden professors and their pupil had been, and a perfect fury set in for more experiments. A professor of the University of Leipzig, in Germany, Dr. Winckler, started the excitement by submitting his body to frequent powerful shocks, opening up, besides, a scientific discussion in which he came forth as the champion of the proposition that the discovery of the ‘Leyden phial’ was due, not to the professors in the Dutch university, but to a German ecclesiastic, Ewald George von Kleist, who made the experiments of Messrs. Allamand and Van Musschenbroek a year before them. His own sensations in submitting to the force of electric shocks, Professor Winckler described, doubtless with some exaggeration, as being convulsed from head to toe, and the prey of violent agitations, which threw his arms about, and made the blood rush from his nose. Dr. Winckler did not venture upon many experiments; but his spouse, undismayed by the arm-shaking and nose-bleeding of her lord, and having the combined curiosity of a woman and a professor’s wife, continued upon her own person the electric shocks. However, she did not take many, nor did science gain by the sacrifice. When a few graspings of the ‘Leyden phial’ had deprived her of the power to walk, and, what was worse, to speak, she followed the example of her bleeding husband, and took ‘cooling medicines.’ All these wonderful facts were made widely known at the time, and created the most profound interest. Professor Musschenbroek, of Leyden, added not a little to the prevailing excitement by writing to his friend René Antoine de Réaumur, inventor of the thermometer named after him, a long letter, given at once to the public, in which he dwelt upon the terrible effects of the mysterious agency which he had helped to call into being, and wound up by declaring that he had become terrified by his own foster-child, and that he would not submit to another electric shock ‘for the whole kingdom of France.’
Experiments in electricity now became the prevailing mania. Louis XV. of France set the fashion among crowned heads of having his soldiers electrified, to see what benefit he, or they, would derive from it. On the instigation of Abbé Nollet, considered a man of high scientific attainments, and who made several important discoveries in electricity, the King submitted, in his own presence, 180 of the tallest men of his life-guards, fastened hand to hand by iron wires, to repeated charges from a connected group of Leyden jars. The big fellows were not visibly influenced by the electric shocks, experiencing not so much as the historical nose-bleeding of Professor Winckler of Leipzig, still less the dumbness of his worthy spouse. On the contrary, the wire-bound royal guards, conscious of but very slight sensations from the electric shocks, and feeling somewhat indignant at this, and of being made scientific tools without at least getting a strong bump on the head, spoke out strongly, declaring the whole matter to be an imposture.
Having failed to electrify his soldiers, Louis XV. tried his monks. It struck his Most Christian Majesty that perhaps the human creatures who had the honour of fighting for him were endowed by nature with rather tough hides, and that the case might be different in regard to the softer beings upon whom devolved the task of praying for him. Accordingly, the King issued orders that all the monks of the grand convent of the Carthusians at Paris, over 700 in number, should be electrified by the same connected group of Leyden jars which had been tried upon the company of life-guards. The result was entirely different, and most gratifying to the King. The shock had no sooner been given when the whole file of monks gave an instantaneous jump, uttering a howl at the same time. There were some eye-witnesses of the affair who asserted that the Carthusians jumped and howled even before the shock had been given, on seeing some one approach the Leyden jar; but this was officially denied. King Louis XV. was so delighted with this result of his scientific investigations, that he proposed to submit all the monks of all the monasteries of France successively to the process of being electrified, so that it might be accurately ascertained upon what religious orders and communities it took the greatest effect. His Majesty likewise was pleased to suggest, that, after all the monks had been electrified, the nuns might be tried in their turn. But the proposal was vetoed at Rome. There came definite orders from the Supreme Pontiff forbidding the contact of any more persons in the service of the holy Catholic Church with the sinful electric wire; and the Carthusians of Paris remained the last monks, as they had been the first, brought to jump and howl at the touch of a Leyden jar.
From France and the continent of Europe the mania for electrical experiments spread into England. But here it was taken up in a thoroughly practical spirit, worthy of the genius of the nation. Instead of aiming merely at the production of wonderful phenomena, made to create astonishment, a number of scientific gentlemen formed themselves into a body for the express purpose of seeking to ascertain the nature, effects, and conditions of the mysterious agent which had obtained the name of electricity. At the head of this body of inquirers was Dr. William Watson, a member of the Royal Society, indefatigable in the pursuit of science, and with him worked Martin Folkes, then president of the Society, Lord Charles Cavendish, Dr. Bevis, and other distinguished men. They set themselves, first of all, to ascertain in what manner electricity was communicated through the solid earth, as well as through fluid bodies; and, secondly, to enter upon experiments showing the amount of speed at which the force travelled. With the first object before them, they made some curious trials in the month of July 1747, which attracted all London. They hung a wire over the Thames, close to Westminster Bridge, attaching the one end to a Leyden jar, and giving the other to a man who held it in the left hand, while he grasped with the right an iron rod, standing in the river. Facing the latter, on the opposite side of the Thames, not far from the operators with the ‘jar,’ was stationed another person, also grasping an iron staff planted in the river. After the charge had been given, it was found that the electricity, after travelling by the wire over the river, had come back by the water, the person holding the iron staff on the starting side not only experiencing a shock himself, but several individuals touching him. Not content with this experiment, showing the transmission of electricity, Dr. Watson and his friends made another, on a larger scale, a week afterwards, on the New River, at Stoke Newington, London. They spanned, by chains and wires, a circuit embracing 800 feet by land and 2,000 by water, with the result of finding that the water transmitted the electric force by itself, if merely an iron staff was placed in it. But they also discovered at the same time that moist land would carry the force, equally with water. To ascertain the latter fact more distinctly, the investigators made a third experiment at Highbury Barn, Islington, setting up some miles of wire, separated partly by land and partly by water. The conduit of the electric force throughout the whole distance was found to be uninterrupted, which led Dr. Watson to proclaim his conviction that the agent was far more abundant throughout nature than had been formerly believed.
In order to ascertain the speed at which the electric force traversed space, Dr. Watson and his friends next entered upon a series of experiments at Shooter’s Hill, near London. They sent an electric discharge a distance of four miles, observers being stationed at each end, and a gun fired at the touch of the Leyden jar, when it was shown conclusively that the movement of the electric force was instantaneous. This was an important step in advance, in overthrowing all formerly established conclusions as to the agency being produced by a succession of waves, like sound, and as such, moving slowly through space.
The field for electrical experiments was now becoming gradually more extensive, and a few more practical tests of Mr. Watson and his coadjutors led the way to the greatest knowledge of the all-pervading force that had yet been achieved, in the clear apprehension that lightning was but a manifestation of electricity. The new experiments were chiefly made with the so-called electrical tube, a glass rod, from two and a half to three feet in length and about an inch in diameter. It had been known for some time that the tube, when gently warmed, so as to be perfectly dry, and rubbed with a silk handkerchief, exhibited strong symptoms of electricity, to the extent of throwing off luminous sparks, which obtained the name of ‘electric fire.’ Dr. Watson found, to his surprise, that this electric fire was not general and always obtainable, but conditional upon circumstances. Having rubbed a glass tube while he was insulated by standing upon a cake of wax, he found that no electricity could be drawn from him by another person who touched any part of his body, but that the same person could obtain sparks from the tube by putting his hand near it. Dr. Watson likewise observed, in the same train of experiments, that if an electrical machine, together with the person turning the handle, were suspended by silk, electric fire was not apparent until he touched the floor with one foot, when the fire appeared upon the conductor. Having made a great number of trials of a like nature, Dr. Watson made known the important conclusion derived from them, namely, that glass tubes and all similar ‘electrifiers’ did not contain within themselves the subtle agent known as electricity, but formed only its temporary place of rest, as a sponge would that of water. Dr. Watson was near proclaiming the fact that electricity resides everywhere throughout the universe; but for a moment he only touched the fringe of it. The discovery of this grand truth was left to later investigators.
One curious result of the experiments made by Dr. Watson and his friends, and which they themselves probably did not expect, was the breaking out of a sort of public frenzy for making like trials, but after the most childish fashion. Everybody who had, or thought he had, the least tincture of science in him, procured a long glass tube, and went on rubbing it assiduously with his handkerchief, sitting in dark rooms and cellars, so as to be better able to watch the first appearance of the ‘electric fire.’ Ladies and gentlemen alike went on rubbing, with desperate energy, as if the fate of the world depended on their exertions. They sold ‘electrical tubes’ in pastry shops; every draper praised his own handkerchiefs as the best for rubbing; and lecturers upon electricity went about through the length and breadth of the land, with glass rods in their hands, delivering wonderful harangues, and trying to explain to gaping multitudes the mysteries of nature as regards electricity. The lecturers even crossed the Atlantic to America, visiting the chief towns, and preaching to large assemblies in places—