When about twenty-one years of age, we find this old young man tired of a drifting life and many projects, and desiring to adopt some occupation permanently. He had courted the girl who had laughed at him, and then gone to England and forgotten her. She had meantime married another man, and was now a widow. In 1730 he married her. Meantime, entering into the printing business on his own account, he often trundled his paper along the streets in a wheelbarrow, and was intensely occupied with his affairs. His acquisitive mind was never idle, and in 1732 he began the publication of the celebrated "Poor Richard's Almanac." This was among the most successful of all American publications, was continued for twenty-five years, and in the last issue, in 1757, he collected the principal matter of all preceding numbers, and the issue was extensively republished in Great Britain, was translated into several foreign languages, and had a world-wide circulation. He was also the publisher of a newspaper, The Pennsylvania Gazette, which was successful and brought him into high consideration as a leader of public opinion in times which were beginning to be troubled by the questions that finally brought about a separation from the mother country.
Time and space would fail in anything like a detailed account of the life of this remarkable man. His only son, the boy who was with him at the flying of the kite, was an illegitimate child, and it is a remarkable instance of unlikeness that this only son became a royalist governor of New Jersey, was never an American in feeling, and removed to England and died there. The sum of Franklin's life is that he was a statesman, a financier of remarkable ability, a skillful diplomat, a law-maker, a powerful and felicitous writer though without imagination or the literary instinct, and a controversialist who seldom, if ever, met his equal. He was always a printer, and at no period of his great career did he lose his affection for the useful arts and common interests of mankind. He is the founder of the American Philosophical Society, and of a college which grew into the present University of Pennsylvania. To him is due the origin of a great hospital which is still doing beneficent work. He raised, and caused to be disciplined, ten thousand men for the defense of the country. He was a successful publisher of the literature of the common people, yet a literature that was renowned. He could turn his attention to the improvement of chimneys, and invented a stove still in use, and still bearing his name as the author of its principle. [[18]] He organized the postal system of the United States before the Union existed. He was a signer of the Declaration of Independence. He sailed as commissioner to France at the age of seventy-one, and gave all his money to his country on the eve of his departure, yet died wealthy for his time. Serene, even-tempered, philosophical, he was yet far-seeing, care-taking, sagacious, and intensely industrious. He acquired a knowledge of the Italian and Spanish languages, and was a proficient French speaker and writer. He possessed, in an extraordinary degree, the power of gaining the regard, even the affection, of his fellow-men. He was even a competent musician, mastering every subject to which his attention was turned; and province-born and reared in the business of melting tallow and setting types, without collegiate education, he shone in association with the men and women who had place in the most brilliant epoch of French intellectual history. At fourscore years he performed the work that would have exhausted a man of forty, and at the same time wrote, for mere amusement, sketches such as the "Dialogue between Franklin and the Gout," and added, with the cool philosophy of all his life still lingering about his closing hours: "When I consider how many terrible diseases the human body is liable to, I think myself well off that I have only three incurable ones, the gout, the stone, and old age."
[18.] The stove was not used in Franklin's time to any extent. The "Franklin Stove" was a fireplace so far as the advantages were concerned, such as ventilation and the pleasure of an open fire. But it also radiated heat from the back and sides as well as the front, and was intended to sit further out into a room; to be both fireplace and stove.
After Franklin, electrical experiments went on with varying results, confined within what now seems to have been a very narrow field, until 1790. The great facts outside of the startling disclosure made by Franklin's experiments remained unknown. It was another forty years of amused and interested playing with a scientific toy. But in that year the key to the utility of electricity was found by one Galvani. He was not an electrician at all, but a professor of anatomy in the university of Bologna. It may be mentioned in passing that he never knew the weight or purport of his own discovery, and died supposing and insisting that the electric fluid he fancied he had discovered had its origin in the animal tissues. Misapprehending all, he was yet unconsciously the first experimenter in what we, for convenience, designate dynamic electricity. He knew only of animal electricity, and called it by that name; a misnomer and a mistake of fact, and the cause of an early scientific quarrel the promoting of which was the actual reason of the advance that was made in the science following his accidental and enormously important discovery.
There are many stories of the details of the ordinarily entirely unimportant circumstances that led to Galvanism and the Galvanic Battery. Volta actually made this battery, then known as the Voltaic Pile, but he made it because of Galvani's discovery. The reader is requested to bear these names in mind; Galvani and Volta. They have a unique claim upon us. With others that will follow, they have descended to all posterity in the immortal nomenclature of the science of electricity. It is through the accidental discovery of the plodding demonstrator of anatomy in a medical college, a man who died at last in poverty and in ignorance of the meaning of his own work, that we have now the vast web of telegraph and telephone wires that hangs above the paths of men in every civilized country, and the cables that lie in the ooze of the oceans from continent to continent. His discovery was the result of one of the commonest incidents of domestic life. Variously described by various writers, the actual circumstance seems reducible to this.
In Galvani's kitchen there was an iron railing, and immediately above the railing some copper hooks, used for the purpose of hanging thereon uncooked meats. His wife was an invalid, and wishing to tempt her appetite he had prepared a frog by skinning it, and had hung it upon one of the copper hooks. The only use intended to be asked of this renowned batrachian was the making of a little broth. Another part of the skinned anatomy touched the iron rail below, and the anatomist observed that this casual contact produced a convulsive twitching of the dead reptile's legs. He groped about this fact for many years. He fancied he had discovered the principle of life. He made the phenomenon to hang upon the facts clustering about his own profession, familiar to him, and about which it was natural for him to think. He promulgated theories about it that are all now absurd, however tenable then. His was an instance of how the fatuities of men in all the fields of science, faith or morals, have often led to results as extraordinary as they have been unexpected. That he died in poverty in 1798 is a mere human fact. That in this life he never knew is merely another. It is but a part of that sadness that, through life, and, indeed, through all history, hangs over the earthly limitations of the immortal mind.
Volta, his contemporary and countryman, finally solved the problem as to the reason why. and made that "Voltaic Pile" which came to be our modern "battery." Acting upon the hint given by Galvani's accident, this pile was made of thin sheets of metal, say of copper and zinc, laid in series one above the other, with a piece of cloth wet with dilute acid interposed between each sheet and the next. The sheets were connected at the edges in pairs, a sheet of zinc to a sheet of copper, and the pile began with a sheet of one metal and ended with one of the other. It is to be noted that a single pair would have produced the same result as a hundred pairs, only more feebly. A single large pair is, indeed, the modern electric battery of one cell. The beginning and the ending sheets of the Voltaic pile were connected by a wire, through which the current passed. We, in our commonest industrial battery, use the two pieces of metal with the fluid between. The metals are usually copper and zinc, and the fluid is water in which is dissolved sulphate of copper. The wire connection we make hundreds of miles long, and over this wire passes the current. If we part this wire the current ceases. If we join it again we instantly renew it. There are many forms of this battery. The two metals, the electrodes, are not necessarily zinc and copper and no others. The acidulated fluid is not invariably water with sulphate of copper dissolved in it. Yet in all modifications the same thing is done in essentially the same way, and the Voltaic pile, and a little back of that Galvani's frog, is the secret of the telegraph, the telephone, the telautograph, the cable message. In the case of Galvani's frog, the fluids of the recently killed body furnished the liquid containing the acid, the copper hook and the iron railing furnished the dissimilar metals, and the nerves and muscles of the frog's body, connecting the two metals, furnished the wire. They were as good as Franklin's wet string was. The effect of the passage of a current of electricity through a muscle is to cause it to spasmodically contract, as everyone knows who has held the metallic handles of an ordinary small battery. Many years passed before the mystery that has long been plain was solved by acute minds. Galvani thought he saw the electric quality in the tissues of the frog. Volta came to see them as produced by chemical action upon two dissimilar metals. The first could not maintain his theories against facts that became apparent in the course of the investigations of several years, yet he asserted them with all the pertinacious conservatism of his profession, which it has required ages to wear away, and died poor and unhonored. The other became a nobleman and a senator, and wore medals and honors. It is a world in which success alone is seen, and in which it may be truthfully said that the contortions of an eviscerated and unconscious frog upon a casual hook were the not very remote cause of the greatest advancements and discoveries of modern civilization.
Yet the mystery is not yet entirely explained. In the study of electricity we are accustomed to accept demonstrated facts as we find them. When it is asked how a battery acts, what produces the mysterious current, the only answer that can now be given is that it is by the conversion of the energy of chemical affinity into the energy of electrical vibrations. Many mixtures produce heat. The explanation can be no clearer than that for electricity. Electricity and heat are both forms of energy, and, indeed, are so similar that one is almost synonymous with the other. The enquiry into the original sources of energy, latent but present always, will, when finally answered, give us an insight into mysteries that we can only now infer are reserved for that hereafter, here or elsewhere, which it is part of our nature to believe in and hope for. The theory of electrical vibrations is explained elsewhere as the only tenable one by which to account for electrical action. One may also ask how fire burns, or, rather, why a burning produces what we call "heat," and the actual question cannot be answered. The action of fire in consuming fuel, and the action of chemicals in consuming metals, are similar actions. They each result in the production of a new form of energy, and of energy in the form of vibrations. In the action of fire the vibrations are irregular and spasmodic; in electricity they are controlled by a certain rhythm or regularity. Between heat and electricity there is apparently only this difference, and they are so similar, and one is so readily converted into the other, that it is a current scientific theory that one is only a modified form of the other. Many acute minds have reflected upon the problem of how to convert the latent energy of coal into the energy of electricity without the interposition of the steam engine and machinery. There apparently exist reasons why the problem will never be solved. There is no intelligence equal to answering the question as to precisely where the heat came from, or how it came, that instantly results upon the striking of a common match. It was evolved through friction. The means were necessary. Friction, or its precise equivalent in energy, must occur. The result is as strange, and in the same manner strange, as any of the phenomena of electricity. Precisely here, in the beginning of the study of these phenomena, the student should be warned that an attitude of wonder or of awe is not one of enquiry. The demonstrations of electricity are startling chiefly for three reasons: newness, silence, and inconceivable rapidity of action. Let one hold a wire in one's hand six or eight inches from the end, and then insert that end into the flame of a gas-jet. It is as old as human experience that that part of the wire which is not in the flame finally grows hot, and burns one's fingers. A change has taken place in the molecules of the wire that is not visible, is noiseless, and that has traveled along the wire. It excites neither wonder nor remark. No one asks the reason why. Yet it cannot be explained except by some theory more or less tenable, and the phenomenon, in kind though not in degree, is as unaccountable as anything in the magic of electricity. In a true sense there is, nothing supernatural, or even wonderful, in all the vast universe of law. If we would learn the facts in regard to anything, it must be after we have passed the stage of wonder or of reverence in respect to it. That which was the "Voice of God"--as truly, in a sense, it was and is--until Franklin's day, has since been a concussion of the air, an echo among the clouds, the passage of an electric discharge. It is the first lesson for all those who would understand.