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‘First let me talk with this philosopher: What is the cause of thunder?’ asks Shakspeare in ‘King Lear’ but without giving a reply. The ‘philosopher’ of Shakspeare’s days had no answer to make; nor had any others long after. From the dawn of history till within comparatively modern times, thunder and lightning were mysteries to the human mind; nor did there exist so much as a surmise that there might be any connection between them and the equally mysterious agent called electricity. The latter force indeed revealed itself early to attentive observers, though in forms very different from those known at the present time. The Greeks found out that amber, or ‘electron,’ attracted certain other bodies under friction, and named the force after it; and the Romans were aware that the shocks discharged by the torpedo fish were of electrical nature, and they used them for the cure of rheumatic complaints in the reign of the Emperor Tiberius. Both Greeks and Romans also observed the sparks emitted, under certain circumstances, from clothing and from the fur of animals. But this represented the total sum of knowledge about electricity for ages and ages.

It was not until the year 1600 that Dr. William Gilbert, physician to Queen Elizabeth, made a great step forward by showing in his celebrated work, ‘De magnete, magneticisque corporibus, et de magno magnete tellure, physiologia nova,’ that the two classes of phenomena, the magnetic and the electric, are emanations of a single fundamental force pervading all nature. Dr. Gilbert further discovered that many other substances besides amber possess the electric power, and that this power is easily excited when the air is dry and cool, and with difficulty when it is moist and warm. These discoveries caused great commotion in the European learned world, yet produced no further result for another half a century. In 1650, Otto von Guericke, burgomaster of Magdeburg, the inventor of the air-pump, who had studied with deep interest Dr. Gilbert’s book, succeeded in constructing a little electrical machine, composed mainly of a ball of sulphur mounted on a revolving axis. By the aid of this instrument, very rude in construction, he produced powerful sparks and flashes of electric light, and it helped him likewise to discover, first, that bodies excited by friction communicate their electricity to other bodies by mere contact, and, secondly, that there resides in electrified substances the power of repulsion as well as that of attraction.

Those who followed in the wake of the ingenious burgomaster of Magdeburg for the next ninety or hundred years, till towards the middle of the eighteenth century, did very little towards adding to the already acquired knowledge of electricity. Sir Isaac Newton constructed an electrical machine of glass, very superior to that of Otto von Guericke, with which he made some amusing experiments; but, strangely enough, drew no conclusions from them, treating the mighty force under his eyes as only a plaything. This was all the more singular as a contemporary of the great philosopher, Francis Hauksbee, like him a Fellow of the Royal Society, called attention, in a volume entitled ‘Physico-mechanical Experiments,’ published in 1709, to the great similarity between the electric flash and lightning, hinting that the two might possibly be offspring of the same mysterious force. Dr. Wall, in 1708, said that the light and crackling of rubbed amber seemed in some degree to represent thunder and lightning. Another member of the Royal Society, Stephen Gray—the first man in England who made the study of electricity the devotion of his life, but of whose career very little is known beyond the fact that he was very poor, and a pensioner of the Charterhouse—added numberless experiments to those previously made, and was bold enough to declare, in 1720, six years before Sir Isaac Newton’s death, that ‘electricity seems to be of the same nature with thunder and lightning—if we may compare great things with small.’ For this audacity in ‘comparing things’ he was sharply taken to task by all the scientific men of the age, and, as deserved, set down as a man out of his senses.

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—

Where blind and naked ignorance

Delivers brawling judgments, unabashed

On all things, all day long.

If it was a ludicrous spectacle to see these wandering lecturers, with their glass tubes and pocket-handkerchiefs, the movement nevertheless produced, apparently quite by accident, a striking result. It occurred through one of the peripatetic preachers of electric revelation coming face to face with Benjamin Franklin, a printer established at Philadelphia, when on a visit to his native town of Boston, Massachusetts, North America.

There are, in the records of scientific discovery, few figures so interesting, because so full of marked individualism, as that of Benjamin Franklin. He was not a man of genius, in the accepted sense of the word; nor was he even a man of high talents. But he was nevertheless a decidedly great man, his greatness consisting in the largest development of that undefined faculty known as common sense. Benjamin Franklin was the very ideal of a ‘practical’ man, that is, a man valuing thoughts only as leading to actions, and new ideas only as the road to visible results. The success of his career in life was but an illustration of his thoroughly practical character. Born at Boston in January 1706, the son of a tallow-chandler and soap-boiler, he was destined by his parents to follow the same trade, but not relishing the melting pots, he got apprenticed to an elder brother, a printer at Boston. Harsh treatment drove him away from this place before the terms of his apprenticeship were over, and with scarcely a penny in his pocket, and the experience of only seventeen years in his brain, he made his way to Philadelphia. A year after, when eighteen years of age, he was induced to sail for England, and was fortunate enough to find employment as a compositor in a printing office in London, but so poor as to be compelled to take a lodging for eighteen-pence a week. However, his self-reliance never deserted him; he managed to go unscathed through all the perils of poverty and friendlessness in a great city, and after a few years went back to Philadelphia, with a small stock of money and a wealth of experience. He now set up as a master printer, and gradually, though by very slow degrees and ceaseless toil, devoted to multifarious objects, rose into prosperity. For upwards of twenty years, from 1728 to 1748, he was the most energetic and active man of business in Philadelphia. He was not only a printer, but an author, an editor of newspapers, a compiler of almanacks, a publisher, a bookseller, a bookbinder, and a stationer. He made lamp-black and ink; he dealt in rags; he sold soap and geese feathers; also, as he frequently made known to his fellow-townsmen in printed notices, he had always in stock ‘very good sack at six shillings a gallon.’ To dispose of the numerous articles in his store he invented the art of advertising, unknown before him at Philadelphia. All the inquiring minds of the ‘Quaker City’ assembled regularly in the shop of Benjamin Franklin, ‘the new printing office near the market,’ which came to form the centre of intelligence, and the source from which all public movements went forth.

The reward for all this activity was that at the end of twenty years Benjamin Franklin had accumulated a handsome fortune, his average income amounting to over two thousand pounds sterling a year: then considered a very large sum, and of probably three times the purchase value it would possess at the present day. With increasing wealth, the active printer, happy in all his family relations, thought himself justified to seek a little occasional leisure, which he found chiefly in visits to Boston, his native town. It was on one of these visits, made in the summer of 1746, that he went with a friend to a lecture-hall, scarcely knowing what was to be the intellectual entertainment prepared for him. It proved a discourse, with illustrative experiments, upon electricity, by a Dr. Spence, duly armed with a three-feet glass rod and silk pocket-handkerchief. Benjamin Franklin was not merely interested: he was startled. It was to him, as he afterwards declared to one of his friends, the opening of a new world.

Perhaps the subject which attracted so suddenly the attention of Benjamin Franklin might have escaped it again, in the pursuit of his many vocations, but for another accidental circumstance. It so happened that, immediately after his return to Philadelphia, there came a parcel of books from England, accompanied by a present in the shape of an electrical tube. The sender of it was the London agent of the Library Company of Philadelphia, Mr. Peter Collinson, a member of the Royal Society, and as such sharing the general interest in the electrical experiments of Dr. Watson. The tube, which was accompanied with full directions for its use, was no sooner unpacked, than Franklin seized it eagerly and began experimenting, at the same time inspiring the most sanguine of his friends to follow his example. Glass tubes, made similar to the one sent from London, were soon procured from a local manufacturer, and then began a general rubbing. ‘I never before,’ Franklin wrote, early in 1747, ‘was engaged in any study that so totally engrossed my attention and my time as this has lately done; for what with making experiments when I can be alone, and repeating them to my friends and acquaintances, who, from the novelty of the thing, come continually in crowds to see them, I have, during some months past, had little leisure for anything else.’ To the greater number of those friends and acquaintances who came flocking in crowds to the shop of the Philadelphia printer, the electric tube was, probably, only looked upon as a new toy; but it was vastly different as regarded himself. His keen practical eye seemed to discern at once that the manifestations of the mysterious force on which he was experimenting contained the germ of something that might be utilised by men, or brought into obedience to the human will.

It is not very clear from the published correspondence of Franklin what his earliest views on the subject were, but there are many indications that he conceived for a while that the ‘electric fire’ might be employed in arts and manufactures. In his usual humorous style he spoke of these utilitarian aims of his in a letter to Mr. Peter Collinson, written in the early summer of 1747: ‘Chagrined a little that we have not been able to produce hitherto anything in the way of use to mankind,’ he wrote, ‘and the hot weather coming on, when electrical experiments are not so agreeable, it is proposed to put an end to them, for this season, in a party of pleasure on the banks of the Schuylkill. Spirits at this party are to be fired by a spark sent from side to side through the river, without any other conductor than the water: an experiment which we some time since performed, to the amazement of many. Then a turkey is to be killed for our dinner by the electrical shock, and roasted by the electrical jack, before a fire kindled by the electrified bottle, when the healths of all the famous electricians in England, Holland, France, and Germany are to be drunk in electrified bumpers, under the discharge of guns from the electrical battery.’

The longer he experimented, the more fascinated grew Benjamin Franklin with his study of the phenomena of electricity. In order to be able to devote himself completely to his darling science, he sold his printing and publishing business in the year 1748, and went to live in a suburb of Philadelphia, not far from the banks of the Delaware. At the same time he purchased a complete set of electrical apparatus, the best that had yet been manufactured, which had been brought over from Europe by the same Dr. Spence who had given him his first ideas about electricity at Boston. With these more perfect means he now continued his investigations, arriving before long at results that formed an epoch in the history of electricity.

The results achieved were wholly of a practical kind. With that strong common sense which formed the most marked feature of his character, Benjamin Franklin, at a very early period of his experiments, came to the conclusion that of the actual nature of electricity we know nothing, and, in all probability, never can know anything, with our finite senses. But, never losing sight of this starting point, he treated electricity as astronomers do the movement of the heavenly bodies. Of the incomprehensible forces that keep countless worlds in their courses through measureless space, astronomers know no more than the most ignorant of mankind; still they are able to arrive at very accurate calculations concerning the directions followed by stars and planets, and the amount of time consumed in their wanderings through the inconceivable universe. To such astronomical endeavours Franklin limited all his researches, and it was precisely because he so limited them that he achieved greater successes than any other investigator of the phenomena of electricity.

Together with many smaller matters, Benjamin Franklin added three great discoveries to the knowledge of electricity. The first was that the electric fluid—so called for want of a better word to express the action of the mysterious force—will run its course more easily and quickly through sharply pointed metals than in any other way. This had never before been demonstrated, nor, probably, been ascertained. The second great discovery of Franklin was that of positive and negative electricity, or, as he called it for some time, plus and minus, the latter names being really the most descriptive. Of the actual existence of these two divisions of the great and marvellous agency, now attracting and now repelling each other, much was known previous to Franklin, but he was the first to make them clearly understood, and to bring their effects within reach of calculation. To these two discoveries Benjamin Franklin added a third, the greatest of all. He established the identity between the electric force and lightning, and upon it based one of the noblest inventions of all ages, that of the lightning conductor. And perhaps there never was any invention acknowledged more deeply by mankind. The French Academy expressed it when, on Franklin’s entrance, all the members rose, and the President exclaimed ‘Eripuit cœlo fulmen.’

The identity of the electric force and lightning, vaguely surmised by previous inquirers, and expressed at times in hints, was not only firmly asserted by Benjamin Franklin, but at a comparatively early part of his investigations proved by him in experiments. His broad practical way of looking at facts succeeded in grasping a truth which all the learned men before him, who had busied themselves with electrical experiments, had not been able to lay hold of, simply because they lost themselves in philosophical abstractions. The professors sought the unattainable, and he confined himself strictly to what he considered within reach, and it was thus he gained his end.

The thoroughly matter-of-fact way in which Franklin went to work is strikingly exhibited in his own description as to how he came to the conclusion of the oneness of lightning and electricity. In reply to a friend and correspondent, living in South Carolina, who had asked him how he came to such an ‘out-of-the-way idea’ as that of the majestic fire from the cloud-capped firmament being exactly the same with the puny gleam from a stick of glass, rubbed with the sleeve of an old coat, Franklin wrote a highly characteristic letter. ‘I cannot answer your question better,’ he told his friend, ‘than by giving you an extract from the minutes I used to keep of the experiments I made. By this extract you will see that the thought was not so much an out-of-the-way one but that it might have occurred to any electrician. The extract, dated November 7, 1749—a date worth remembrance in the history of scientific progress—was as follows in its entirety:—‘Electrical fluid agrees with lightning, in these particulars: 1. Giving light. 2. The colour of the light. 3. In the crooked direction of the flame. 4. In the swift motion. 5. In being conducted by metals. 6. In the crack, or noise, of the explosion. 7. The subsisting in water, or ice. 8. In the rending of bodies it passes through. 9. In destroying animals. 10. In melting metals. 11. In firing inflammable substances. 12. The sulphurous smell. The electric fluid is attracted by points, and we do not know whether this property is in lightning. But since they agree in all the particulars wherein we can already compare them, is it not probable that they agree likewise in this? Let the experiment be made.’