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Benjamin Franklin's activity and resource in the field of invention really partook of the intellectual breadth of the man of whom Turgot wrote:

"Eripuit cœlo fulmen, sceptrumque tyrannis."

"He snatched the thunderbolt from heaven,

And the sceptre from the hands of tyrants."

And of which bit of verse Franklin once dryly remarked, that as to the thunder, he left it where he found it, and that more than a million of his countrymen co-operated with him in snatching the sceptre. Those persons who knew Franklin, the inventor, only as the genius to whom we owe the lightning-rod, will be amazed at the range of his activity. For half a century his mind seems to have been on the alert concerning the why and wherefore of every phenomenon for which the explanation was not apparent. Nothing in nature failed to interest him. Had he lived in an era of patents he might have rivalled Edison in the number of his patentable devices, and had he chosen to make money from such devices, his gains would certainly have been fabulous. As a matter of fact, Franklin never applied for a patent, though frequently urged to do so, and he made no money by his inventions. One of the most popular of these, the Franklin stove, which device, after a half-century of disuse, is now again popular, he made a present to his early friend, Robert Grace, an iron founder, who made a business of it. The Governor of Pennsylvania offered to give Franklin a monopoly of the sale of these stoves for a number of years. "But I declined it," writes the inventor, "from a principle which has ever weighed with me on such occasions, viz.: That as we enjoy great advantages from the inventions of others, we should be glad of an opportunity to serve others by any invention of ours; and this we should do freely and generously. An ironmonger in London, however, assuming a good deal of my pamphlet (describing the principle and working of the stove), and working it up into his own, and making some small change in the machine, which rather hurt its operation, got a patent for it there, and made, as I was told, a little fortune by it."

The Franklin Stove.

The complete list of inventions, devices, and improvements of which Franklin was the originator, or a leading spirit and contributor, is so long a one that a dozen pages would not suffice for it. I give here a brief summary, as compiled by Parton in his excellent "Life of Franklin." "It is incredible," Franklin once wrote, "the quantity of good that may be done in a country by a single man who will make a business of it and not suffer himself to be diverted from that purpose by different avocations, studies, or amusements." As a commentary upon this sentiment, here is a catalogue of the achievements of Benjamin Franklin that may fairly come under the title of inventions:

He established and inspired the Junto, the most useful and pleasant American club of which we have knowledge.

He founded the Philadelphia Library, parent of a thousand libraries, and which marked the beginning of an intellectual movement of endless good to the whole country.

He first turned to great account the engine of advertising, an indispensable element in modern business.

He published "Poor Richard," a record of homely wisdom in such shape that hundreds of thousands of readers were made better and stronger by it.

He created the post-office system of America, and was the first champion of a reformed spelling.

He invented the Franklin stove, which economized fuel, and suggested valuable improvements in ventilation and the building of chimneys.

He robbed thunder of its terrors and lightning of some of its power to destroy.

He founded the American Philosophical Society, the first organization in America of the friends of science.

He suggested the use of mineral manures, introduced the basket willow, promoted the early culture of silk, and pointed out the advisability of white clothing in hot weather.

He measured the temperature of the Gulf Stream, and discovered that northeast storms may begin in the southwest.

He pointed out the advantage of building ships in water-tight compartments, taking the hint from the Chinese, and first urged the use of oil as a means of quieting dangerous seas.

Besides these great achievements, accomplished largely as recreation from his life work as economist and statesman, Benjamin Franklin helped the whole race of inventors by a remark that has been of incalculable value and comfort to theorists and dreamers the world over. When someone spoke rather contemptuously in Franklin's presence of Montgolfier's balloon experiments, and asked of what use they were, the great American replied in words now historic: "Of what use is a new-born babe?"

"This self-taught American," said Lord Jeffrey, in the Edinburgh Review of July, 1806, "is the most rational, perhaps, of all philosophers. He never loses sight of common sense in any of his speculations. No individual, perhaps, ever possessed a greater understanding, or was so seldom obstructed in the use of it by indolence, enthusiasm, or authority. Dr. Franklin received no regular education; and he spent the greater part of his life in a society where there was no relish and no encouragement for literature. On an ordinary mind, these circumstances would have produced their usual effects, of repressing all sorts of intellectual ambition or activity, and perpetuating a generation of incurious mechanics; but to an understanding like Franklin's, we cannot help considering them as peculiarly propitious, and imagine that we can trace back to them distinctly almost all the peculiarities of his intellectual character."

Franklin's Birthplace, Boston.

The main outlines of Franklin's life and career are so familiar to everyone, that I may as well pass at once to the story of his work as an inventor. We all know, or ought to know, that Benjamin, the fifteenth child of Josiah Franklin, the Boston soap-boiler, was born in that town on the 17th of January, 1706, and established himself as a printer in Philadelphia in 1728. That he prospered and founded the Gazette a few years later, and became Postmaster of Philadelphia in 1737; that after valuable services to the Colonies as their agent in England, he was appointed United States Minister at the Court of France upon the Declaration of Independence; and that in 1782 he had the supreme satisfaction of signing at Paris the treaty of peace with England by which the independence of the Colonies was assured. That he died full of honors at Philadelphia in April, 1790, and that Congress, as a testimony of the gratitude of the Thirteen States and of their sorrow for his loss, appointed a general mourning throughout the States for a period of two months.

Franklin Entering Philadelphia.

The great invention or discovery which entitles Benjamin Franklin to rank at the head of American inventors was, of course, the identification of lightning with electricity, and his suggestion of metallic conductors so arranged as to render the discharge from the clouds a harmless one. In order to appreciate the originality and value of this discovery, it is necessary to review briefly what the world knew of the subject at that day.

For a hundred years before Franklin's time, electricity had been studied in Europe without much distinct progress resulting. A thousand experiments had been performed and described. Gunpowder had been exploded by the spark from a lady's finger, and children had been insulated by hanging them from the ceiling by silk cords. A tolerable machine had been devised for exciting electricity, though most experimenters still used a glass tube. Several volumes of electrical observations and experiments had appeared, and yet what had been done was little more than a repetition on a larger scale, and with better means, of the original experiment of rubbing a piece of amber on the sleeve of the philosopher's coat. Experimenters in 1745 could produce a more powerful spark and play a greater variety of tricks with it than Dr. Gilbert, the English experimenter of 1600, but that was about all the advantage they had over him.

So-called experts had attempted, with more or less satisfaction to themselves, to answer the question addressed by the mad Lear to poor Tom: "Let me talk with this philosopher. What is the cause of thunder?" Pliny thought he had explained it when he called it an earthquake in the air. Dr. Lister announced that lightning was caused by the sudden ignition of immense quantities of fine floating sulphur. Jonathan Edwards, in his diary of 1722, records the popular impression of the day upon this subject: "Lightning," he says, "seem to be an almost infinitely fine combustible matter, that floats in the air, that takes fire by sudden and mighty fermentation, that is some way promoted by the cool and moisture, and perhaps attraction of the clouds. By this sudden agitation, this fine floating matter is driven forth with a mighty force one way or other, whichever way it is directed, by the circumstances and temperature of the circumjacent air; for cold and heat, density and rarity, moisture and dryness, have almost an infinitely strong influence upon the fine particles of matter. This fluid matter thus projected, still fermenting to the same degree, divides the air as it goes, and every moment receives a new impulse by the continued fermentation; and as its motion received its direction, at first, from the different temperature of the air on different sides, so its direction is changed, according to the temperature of the air it meets with, which renders the path of the lightning so crooked."

Even this explanation was a daring bit of speculation in Jonathan Edwards, for thunder and lightning were then commonly regarded as the physical expression of God's wrath against the insects He had created.

Mr. Peter Collinson, the London agent of the library that Franklin had founded in Philadelphia in 1732, was accustomed to send over with the annual parcel of books any work or curious object that chanced to be in vogue in London at the time. In 1746 he sent one of the new electrical tubes with a paper of directions for using it. The tubes then commonly used were two feet and a half long, and as thick as a man could conveniently grasp. They were rubbed with a piece of cloth or buckskin, and held in contact with the object to be charged. Franklin had already seen one of these tubes in Boston, and had been astonished by its properties. No sooner, therefore, was it unpacked at the Library, than he repeated the experiments he had seen in Boston, as well as those described by Collinson. The subject completely fascinated him. He gave himself up to it. Procuring other tubes, he distributed them among his friends and set them all rubbing. "I never," he writes in 1747, "was before engaged in any study that so totally engrossed my attention and my time as this has done; for what with making experiments when I can be alone, and repeating 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."

Franklin claimed no credit for what he achieved in electricity. During the winter of 1746-7 he and his friends experimented frequently, and observed electrical attraction and repulsion with care. That electricity was not created, but only collected by friction, was one of their first conjectures, the correctness of which they soon demonstrated by a number of experiments. Before having heard of the Leyden jar coated with tin-foil, these Philadelphia experimenters substituted granulated lead for the water employed by Professor Maschenbroeck. They fired spirits and lighted candles with the electric spark. They performed rare tricks with a spider made of burnt cork. Philip Syng mounted one of the tubes upon a crank and employed a cannon-ball as a prime conductor, thus obtaining the same result without much tedious rubbing of the tube.

The summer of 1747 was devoted to preparing the province for defence. But during the following winter the Philadelphians resumed their experiments. The wondrous Leyden jar was the object of Franklin's constant observation. His method of work is well shown in his own account of an experiment during this winter. The jar used was Maschenbroeck's original device of a bottle of water with a wire running through the cork.

"Purposing," writes Franklin, "to analyse the electrified bottle, in order to find wherein its strength lay, we placed it on glass, and drew out the cork and wire, which for that purpose had been loosely put in. Then, taking the bottle in one hand, and bringing a finger of the other near its mouth, a strong spark came from the water, and the shock was as violent as if the wire had remained in it, which showed that the force did not lie in the wire. Then, to find if it resided in the water, being crowded into and condensed in it, as confined by the glass, which had been our former opinion, we electrified the bottle again, and placing it on glass, drew out the wire and cork as before; then, taking up the bottle, we decanted all its water into an empty bottle, which likewise stood on glass; and taking up that other bottle, we expected, if the force resided in the water, to find a shock from it. But there was none. We judged then that it must either be lost in decanting or remain in the first bottle. The latter we found to be true; for that bottle on trial gave the shock, though filled up as it stood with fresh unelectrified water from a tea-pot. To find, then, whether glass had this property merely as glass, or whether the form contributed anything to it, we took a pane of sash glass, and laying it on the hand, placed a plate of lead on its upper surface; then electrified that plate, and bringing a finger to it, there was a spark and shock. We then took two plates of lead of equal dimensions, but less than the glass by two inches every way, and electrified the glass between them, by electrifying the uppermost lead; then separated the glass from the lead, in doing which, what little fire might be in the lead was taken out, and the glass being touched in the electrified parts with a finger, afforded only very small pricking sparks, but a great number of them might be taken from different places. Then dexterously placing it again between the leaden plates, and completing a circle between the two surfaces, a violent shock ensued; which demonstrated the power to reside in glass as glass, and that the non-electrics in contact served only, like the armature of a loadstone, to unite the force of the several parts, and bring them at once to any point desired; it being the property of a non-electric, that the whole body instantly receives or gives what electrical fire is given to, or taken from, any one of its parts.

"Upon this we made what we called an electrical battery, consisting of eleven panes of large sash glass, armed with thin leaden plates, pasted on each side, placed vertically, and supported at two inches' distance on silk cords, with thick hooks of leaden wire, one from each side, standing upright, distant from each other, and convenient communications of wire and chain, from the giving side of one pane to the receiving side of the other; that so the whole might be charged together with the same labor as one single pane."

In 1748 Franklin, being then forty-two years old, and in the enjoyment of an ample income from his business as printer and publisher, sold out to his foreman, David Hall, and was free to devote himself wholly to his beloved experiments. He had built himself a home in a retired spot on the outskirts of Philadelphia, and with an income which in our days would be equivalent to $15,000 or $20,000 a year, he was considered a fairly rich man. Having thus settled his business affairs in a manner which proved that he knew perfectly well what money was worth, he took up his electrical studies again and extended them from the machine to the part played in nature by electricity. The patience with which he observed the electrical phenomena of the heavens, the acuteness displayed by him in drawing plausible inferences from his observations, and the rapidity with which he arrived at all that we now know of thunder and lightning, still excite the astonishment of all who read the narratives he has left us of his proceedings. During the whole winter of 1748-49 and the summer following, he was feeling his way to his final conclusions on the subject. Early in 1749 he drew up a series of fifty-six observations, entitled "Observations and Suppositions towards forming a new Hypothesis for explaining the several Phenomena of Thundergusts." Nearly all that he afterward demonstrated on this subject is anticipated in this truly remarkable paper, which was soon followed by the most famous of all his electrical writings, that entitled "Opinions and Conjectures concerning the Properties and Effects of the Electrical Matter, and the Means of preserving Buildings, Ships, etc., from Lightning; arising from Experiments and Observations made at Philadelphia, 1749."

Franklin sets forth in this masterly paper the similarity of electricity and lightning, and the property of points to draw off electricity. It is this treatise which contains the two suggestions that gave to the name of Franklin its first celebrity. Both suggestions are contained in one brief passage, which follows the description of a splendid experiment, in which a miniature lightning-rod had conducted harmlessly away the electricity of an artificial thunder-storm.

"If these things are so," continues the philosopher, after stating the results of his experiment, "may not the knowledge of this power of points be of use to mankind in preserving houses, churches, ships, etc., from the stroke of lightning, by directing us to fix on the highest part of those edifices upright rods of iron, made sharp as a needle and gilt to prevent rusting, and from the foot of those rods, a wire down the outside of the building into the ground, or down round one of the shrouds of a ship, and down her side till it reaches the water? Would not these pointed rods probably draw the electrical fire silently out of a cloud before it came nigh enough to strike, and thereby secure us from that most sudden and terrible mischief?"

The second of these immortal suggestions was one that immediately arrested the attention of European electricians when the paper was published. It was in these words:

"To determine the question, whether the clouds that contain lightning are electrified or not, I would propose an experiment to be tried where it may be done conveniently. On the top of some high tower or steeple, place a kind of sentry-box, big enough to contain a man and an electric stand. From the middle of the stand let an iron rod rise and pass, bending out of the door, and then upright twenty or thirty feet, pointed very sharp at the end. If the electrical stand be kept clean and dry, a man standing on it, when such clouds are passing low, might be electrified and afford sparks, the rod drawing fire to him from a cloud. If any danger to the man should be apprehended (though I think there would be none), let him stand on the floor of his box, and now and then bring near to the rod the loop of a wire that has one end fastened to the leads, he holding it by a wax handle; so the sparks, if the rod is electrified, will strike from the rod to the wire and not affect him."

A friend once asked Franklin how he came to hit upon such an idea. His reply was to quote an extract from the minutes he kept of the experiments he made. This extract, dated November 7, 1749, was as follows: "Electrical fluid agrees with lightning in these particulars: 1. Giving light. 2. Color of the light. 3. Crooked direction. 4. Swift motion. 5. Being conducted by metals. 6. Crack or noise in exploding. 7. Subsisting in water or ice. 8. Rending bodies it passes through. 9. Destroying animals. 10. Melting metals. 11. Firing inflammable substances. 12. Sulphurous smell. The electric fluid is attracted by points. 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 they agree likewise in this? Let the experiment be made."

In this discovery, therefore, there was nothing of chance; it was a legitimate deduction from patiently accumulated facts.

It was not until the spring of 1752 that Franklin thought of making his suggested experiment with a kite. The country around Philadelphia presents no high hills, and he was not aware till later that the roof of any dwelling-house would have answered as well as the peak of Teneriffe. There were no steeples in Philadelphia at that day. The vestry of Christ Church talked about erecting a steeple, but it was not begun until 1753. On the 15th of June, 1752, Franklin decided to fly that immortal kite. Wishing to avoid the ridicule of a failure, he took no one with him except his son, who, by the way, was not the small boy shown in countless pictures of the incident, but a stalwart young man of twenty-two. The kite had been made of a large silk handkerchief, and fitted out with a piece of sharpened iron wire. Part of the string was of hemp, and the part to be held in the hand was of silk. At the end of the hempen string was tied a key, and in a convenient shed was a Leyden jar in which to collect some of the electricity from the clouds. When the first thunder-laden clouds reached the kite, there were no signs of electricity from Franklin's key, but just as he had begun to doubt the success of the experiment, he saw the fibres of the hempen string begin to rise. Approaching his hand to the key, he got an electric spark, and was then able to charge the Leyden jar and get a stronger shock. Then the happy philosopher drew in his wet kite and went home to write his modest account of one of the most notable experiments made by man.

Franklin's fame as the first to suggest the identity of lightning and electricity would have been safe, however, even without the famous kite-flying achievement. A month before that June thunderstorm his suggestions had been put into practice in Europe with complete success. Mr. Peter Collinson, to whom Franklin addressed from time to time long letters about his experiments and conjectures, had caused them to be read at the meetings of the Royal Society, of which he (Collinson) was a member. That learned body, however, did not deem them worthy of publication among its transactions, and a letter of Franklin's containing the substance of his conjectures respecting lightning was laughed at. The only news that reached Philadelphia concerning these letters was that Watson and other English experimenters did not agree with Franklin. It was only in May, 1751, that a pamphlet was finally published in London, entitled "New Experiments and Observations in Electricity, made at Philadelphia, in America." A copy having been presented to the Royal Society, Watson was requested to make an abstract of its contents, which he did, giving generous praise to the author.

Before the year came to a close Franklin was famous. There was something in the drawing down, for mere experiment, of the dread electricity of heaven that appealed not less powerfully to the imagination of the ignorant than to the understanding of the learned. And the marvel was the greater that the bold idea should have come from so remote a place as Philadelphia. By a unanimous vote the Royal Society elected Franklin a member, and the next year bestowed upon him the Copley medal. Yale College and then Harvard bestowed upon him the honorary degree of Master of Arts.