Part 2

"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.

As might have been expected, there was no lack of opposition to the new doctrine of lightning-rods. Every new movement of radical character is denounced more or less fiercely. The last years of Newton's life were perplexed by the charge that his theory of gravitation tended to "materialize" religion. Insuring houses against fire was opposed as an interference with the prerogatives of deity. The establishment of the Royal Society was opposed upon the ground that the study of natural philosophy, grounded, as it was, upon experimental evidence, tended to weaken the force of evidence not so founded; and this objection was deemed of sufficient weight to call for serious answer. Franklin's daring proposal to neutralize the "artillery of heaven," of course could not escape, and the impiety of lightning-rods was widely discussed, often with acrimony. Mr. Kinnersley, one of Franklin's friends, who lectured for several years upon electricity, when advertising the outline of his subject always announced his intention to show that the erection of lightning-rods was "not chargeable with presumption nor inconsistent with any of the principles either of natural or revealed religion." Quincy relates in his "History of Harvard College," that in November, 1755, a shock of earthquake having been felt in New England, a Boston clergyman preached a sermon on the subject, in which he contended that the lightning-rods, by accumulating the electricity in the earth, had caused the earthquake. Professor Winthrop, of Harvard, thought it worth while to defend Franklin. "In 1770," Mr. Quincy adds, "another Boston clergyman opposed the use of the rods on the ground that, as the lightning was one of the means of punishing the sins of mankind, and of warning them from the commission of sin, it was impious to prevent its full execution." And to this attack also Professor Winthrop replied. Apparently Franklin himself thought it wise to conciliate the opposition of some so-called religious people of the day, for an account of the lightning-rod which appears in _Poor Richard's Almanac_ for 1753, written probably by Franklin, begins as follows: "It has pleased God in his Goodness to Mankind, at length to discover to them the means of securing their Habitations and other Buildings from Mischief by Thunder and Lightning."

Franklin bore his honors with the most remarkable modesty. It was in June that he flew his first kite, but not until October that he sent to Mr. Collinson an account of the experiment, and even then he described the manner of making and flying the kite and omitted all reference to his own success with it. The identity of lightning with electricity having been established by M. Dalibard, he deemed it unnecessary to forward the account of an experiment which, however brilliant, he thought superfluous. Accordingly, we have no narrative by Franklin of the flying of the kite. We owe our knowledge of what occurred on that memorable afternoon to persons who heard Franklin tell the story. Franklin prefaces his description of his kite with these words: "As frequent mention is made in public papers from Europe of the success of the Philadelphia experiment for drawing the electric fire from clouds by means of pointed rods of iron erected on high buildings, it may be agreeable to the curious to be informed that the same experiment has succeeded in Philadelphia, though made in a different and more easy manner, which is as follows." And then we have the description of the kite, the letter ending without reference to what he himself had done with it.

Yet he was far from hiding the pleasure his fame brought him. "The _Tatler_," he wrote, in 1753, to a friend, "tells us of a girl who was observed to grow suddenly proud, and none could guess the reason, till it came to be known that she had got on a pair of new silk garters. Lest you should be puzzled to guess the cause, when you observe anything of the kind in me, I think I will not hide my new garters under my petticoats, but take the freedom to show them to you in a paragraph of our friend Collinson's last letter, viz.--But I ought to mortify, and not indulge, this vanity; I will not transcribe the paragraph--yet I cannot forbear." Then he quotes the paragraph, which mentions the honors done him by the King of France and the Royal Society.

For twenty years Franklin continued to work at electricity, devoting most of his leisure to his beloved study. The great practical value of the lightning-rod, at one time in the early part of this century somewhat exaggerated, as a perfect protection against harm by lightning, just as electricity was at one time heralded as a panacea for all bodily ailments, has of late years been questioned, but the consensus of scientific opinion still attributes much merit to the device, and the extent of Franklin's services to science in the matter cannot be called into doubt. Others have claimed his discoveries. The Abbé Nolet, of France, has been credited as being the first to note the similarity between electricity and lightning; and M. Romas, of Nerac, France, is said to have used a kite with a copper wire wound around the string, to attract electricity from clouds, some time before Franklin made his experiment. But posterity has ignored these claimants, and Franklin had the happiness of escaping bitter contentions with rivals. In fact, there could hardly have been a quarrel with a man who claimed nothing, who mentioned with honor everybody's achievements but his own, and who recorded his most brilliant observations in the plural, as though he were but one of a band of investigating Philadelphians.

Passing now, to Franklin's connection with the use of oil to still dangerous waves, I had occasion recently to note that Lieutenant W.H. Beehler, of the United States Navy, in writing upon the matter, quotes Franklin's explanation of why oil works so beneficently as the accepted theory. Franklin was greatly interested, when at sea, in studying the matter. Any phenomenon that puzzled him was fit subject for investigation. Let us see how he went about the inquiry. "In 1757," he wrote, "being at sea in a fleet of ninety-six sail bound against Louisburg, I observed the wakes of two of the ships to be remarkably smooth, while all the others were ruffled by the wind which blew fresh. Being puzzled with the differing appearance, I at last pointed it out to our captain and asked him the meaning of it. 'The cooks,' says he, 'have, I suppose, been just emptying their greasy water through the scuppers, which has greased the sides of those ships a little;' and this answer he gave me with an air of some little contempt, as to a person ignorant of what everybody else knew. In my own mind I at first slighted his solution, though I was not able to think of another; but recollecting what I had formerly read in Pliny, I resolved to make some experiment of the effect of oil on water, when I should have opportunity. Afterwards, being again at sea in 1762, I first observed the wonderful quietness of oil on agitated water, in the swinging glass lamp I made to hang up in the cabin, as described in my printed papers. This I was continually looking at and considering, as an appearance to me inexplicable. An old sea captain, then a passenger with me, thought little of it, supposing it an effect of the same kind with that of oil put on water to smooth it, which he said was a practice of the Bermudians when they would strike fish, which they could not see if the surface of the water was ruffled by the wind. The same gentleman told me he had heard it was a practice with the fishermen of Lisbon, when about to return into the river (if they saw before them too great a surf upon the bar, which they apprehended might fill their boats in passing) to empty a bottle or two of oil into the sea, which would suppress the breakers, and allow them to pass safely. A confirmation of this I have not since had an opportunity of obtaining; but discoursing of it with another person, who had often been in the Mediterranean, I was informed that the divers there, who, when under water in their business, need light, which the curling of the surface interrupts by the refractions of so many little waves, let a small quantity of oil now and then out of their mouths, which rising to the surface smooths it, and permits the light to come down to them. All these informations I at times resolved in my mind, and wondered to find no mention of them in our books of experimental philosophy.

"At length being at Clapham where there is, on the common, a large pond, which I observed one day to be very rough with the wind, I fetched out a cruet of oil and dropped a little of it on the water. I saw it spread itself with surprising swiftness upon the surface; but the effect of smoothing the waves was not produced; for I had applied it first on the leeward side of the pond, where the waves were largest, and the wind drove my oil back upon the shore. I then went to the windward side, where they began to form; and there the oil, though not more than a teaspoonful, produced an instant calm over a space several yards square, which spread amazingly, and extended itself gradually, till it reached the lee side, making all that quarter of the pond, perhaps half an acre, as smooth as a looking glass.

"A gentleman from Rhode Island told me it had been remarked that the harbor of Newport was ever smooth while any whaling vessels were in it; which, probably arose from hence, that the blubber, which they sometimes bring loose in the hold, or the leakage of their barrels, might, afford some oil to mix with that water, which, from time to time, they pump out to keep their vessel free, and that some oil might spread over the surface of the water in the harbor and prevent the forming of any waves."

Thus Franklin collected his facts, taking them far and near, and from anybody and everybody. By dint of observation and reflection he finally solved the problem, arriving at the conclusion that "the wind blowing over water thus covered with a film of oil, cannot easily catch upon it, so as to raise the first wrinkles, but slides over it, and leaves it smooth as it finds it."

Another remarkable instance of Franklin's passion for investigation is afforded in the following interesting letter to Sir John Pringle: "When we were travelling together in Holland, you remarked that the canal boat in one of the stages went slower than usual, and inquired of the boatman what might be the reason; who answered that it had been a dry season, and the water in the canal was low. On being asked if it was so low that the boat touched the muddy bottom, he said no, not so low as that, but so low as to make it harder for the horse to draw the boat. We neither of us at first could conceive that, if there was water enough for the boat to swim clear of the bottom, its being deeper would make any difference. But as the man affirmed it seriously as a thing well known among them, and as the punctuality required in their stages was likely to make such difference, if any there were, more readily observed by them than by other watermen who did not pass so regularly and constantly backwards and forwards in the same track, I began to apprehend there might be something in it, and attempted to account for it from this consideration, that the boat in proceeding along the canal must, in every boat's length of her course, move out of her way a body of water equal in bulk to the room her bottom took up in the water; that the water so moved must pass on each side of her, and under her bottom, to get behind her; that if the passage under her bottom was straitened by the shallows, more of the water must pass by her sides, and with a swifter motion, which would retard her, as moving the contrary way; or that, the water becoming lower behind the boat than before, she was pressed back by the weight of its difference in height, and her motion retarded by having that weight constantly to overcome. But, as it is often lost time to attempt accounting for uncertain facts, I determined to make an experiment of this, when I should have convenient time and opportunity.