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CHAIRMAN'S ANNUAL DISCOURSE FOR 1899, ON THE

TRANSMISSION OF ENERGY BY ELECTRICITY.

BY COLEMAN SELLERS, E.D.,

VICE-PRESIDENT.

(Read February 3, 1899.)

Gentlemen :-According to the old Rules of Administration and Order of the American Philosophical Society held in Philadelphia for the Promotion of Useful Knowledge, it was specified that some time during each year the President of the Society was expected to “deliver a discourse on some literary or scientific subject, accompanied by such suggestions with regard to the affairs of the Society as he shall judge proper." By the new rules, recently adopted, a date has been fixed for this discourse, with the further proviso that the President be authorized at his option to appoint one of the Vice-Presidents to take his place in carrying out the purpose of the rule. On January 14 of this year I received notice from our respected President that he had appointed me to this duty. I have selected as the subject of my discourse “Electricity as Applied to the Transmission of Energy," for a reason to be presently explained.

When the late Dr. William Pepper was elected a Vice-President he made much personal effort to excite an interest among the resident members in a scheme of quarterly meetings to be devoted to subjects of acknowledged importance, at which meetings a paper or papers on a subject selected for discussion should be presented, and a further effort made to insure the presence of, or correspondence from, all members who had given thought to the subject selected. He called on me soon after his election to induce me to prepare a paper on the transmission of power by electricity, or if I preferred not to do so, to have ine suggest some one capable of carrying out the idea. At that time, about two years ago, he expressed some surprise that I should consider the subject matter not yet far enough advanced practically for intelligent presentation or discussion. I promised, however, to correspond with my personal friends interested in electrical work to secure, if possible, contributions of importance that would be acceptable under the traditional requisites of matter fitted for our PROCEEDINGS or our Transactions. What has been or will be accomplished in this direction remains yet to be seen. Since that time the Society has seen fit to honor with mem

PROC. AMER. Philos. soc. XXXVIII. 159. D. PRINTED JULY 10, 1899.

bership many men of distinction in electrical engineering in its broadest sense. From some of these we may expect contributions.

Inasmuch as the founder of this Society, Dr. Benjamin Franklin, attracted attention as a scientist in the domain of natural philosophy by and through his electrical experiments, I think it advisable to call attention to the limited resources at his command, not only when he announced his belief that electricity and lightning were one and the same thing, but even up to the date of his death. I do so mainly to show the close interdependence between scientific research and the practical application of knowledge to the use of man, and further to show how much of the progress in exact scientific knowledge has been gained from the practical work done in experimental research by those who have not had the technical training or the knowledge of the higher mathematics, whereby they would have been able, to the extent of previously collected data, to formulate conditions leading to results in advance of the experimentation that alone can be depended on to prove the correctness of their deductions. I also desire to show how the growing wants of man have excited research, more particularly when commercial demand calls for the practical application of knowledge to any stated end.

Dr. Franklin was an experimenter. His interest in electricity as one of the then little understood but most interesting branches of natural philosophy was brought about through his ability to generate what he called “ electric fire," and to exhibit the effects produced thereby, in conducting the simple experiments possible with the meagre apparatus at his command. It seems that he had received from a friend in London a glass cylinder or rod,' with which simple device, held in one hand and excited to produce electricity by being rubbed with a silken cloth, or the fur side of a catskin, he was able to charge Leyden jars or electric condensers, and thus exhibit the more striking effects of static electricity. The electric sparks from the outset may have impressed him as similar to the lightning flash of “thunder-storms."

In the order of chronological sequence, permit me to call attention to our records to connect this Society with his work.

We know that Dr. Franklin, on April 5, 1744, eight years before his important electrical discovery, wrote to Mr. Colden explaining his idea of a Society for the Promotion of Useful Knowledge, which

1 This rod, in its tin case, is in the collection of the Society.

was the beginning of the American Philosophical Society. Some time between 1747 and 1750 Mr. Philip Syng' is credited with designing a glass globe electrical machine. One of these electrical machines, in perfect order, said to have been the one Franklin made the most use of, is among the highly prized relics owned by the Franklin Institute in this city. All of us who have used electrical apparatus can appreciate the value of Mr. Syng's invention and the help it afforded to Franklin in his experiments. Franklin was, like Prof. Michael Faraday, an experimenter. Neither of these two great men possessed the mathematical habit of thought that distinguished so many philosophers before and since their time; both based all their knowledge on succcessful experiments.

In 1752 Franklin wrote to his friend in London, Mr. Collinson, expressing his grounds for belief in the identity of electricity and lightning. It matters but little now that this important letter was not deemed worth publishing in the Transactions of the Royal Society. Soon after it was received, however, Dr. Fothergill suggested its separate publication. Franklin's discovery thus reached and deeply interested Count de Buffon. It was translated into French, and was read by most learned men of the day. This remarkable and extensive recognition of the discovery induced the Royal Society in 1753, one year later, to make Dr. Franklin a member, without waiting for any formal application in the usual course, and without the payment of any fee or dues as a member. He was also honored the same year with the Copley gold medal for his discovery. Sir Humphrey Davy wrote of Dr. Franklin, in reference to his work, that “a singular facility of induction guided all his researches, and by very simple means he established very great truths. The style and manner of his publications are almost as worthy of admiration as the doctrines they contain. ... . He has written equaily for the uninitiated and for the philosopher.”

Franklin's discovery, whether made by means of a kite in Philadelphia or by lightning rods in France, was turned to important use by his suggested protection of buildings from the effects of lightning, from “ thunderbolts,” or from the so-called electric fire of the clouds.

1 Mr. Philip S. P. Conner says that Philip Syng in Franklin's time was a goldsmith.

2 One such globe, mounted on an axle and provided with a driving pulley, was exhibited, belonging to the cabinet of the Society.

This practical application of his discovery, taken in connection with his improvements in fireplaces, his invention, given freely to the world, of the so-called Franklin stove, and other useful inventions, are proofs of his attention to the question of practical and useful results as the outcome of his philosophical studies based on experiments. To more fully understand the limited knowledge possessed in Franklin's day, even up to his departure from life in 1790, it should be borne in mind that not until 1774, when Dr. Joseph Priestley discovered oxygen, was the chemistry of to-day possible. Priestley's discovery took atmospheric air out of the list of simple elements, and was the beginning of the rapid advance in our knowledge of chemistry. Electricity also had no acknowledged connection during Franklin's lifetime with magnetism. Aloisio Galvani had noted an effect of electricity on animals (in fact, what is now known as galvanic action) in 1780, but what is of more importance to bear in mind, in connection with the limited knowledge possessed by physicists in Franklin's time, is the invention of the voltaic pile (which was the beginning of all galvanic batteries since used), was not perfected by Alexander Volta until 1800 ; therefore, Galvani's and Volta's discoveries had no place in Franklin's studies.

The American Philosophical Society has among its collection some interesting pieces of apparatus of Franklin's time, but, as bearing upon this brief outline of Dr. Franklin's contribution to our knowledge of electricity, a suggestion has been made by Dr. George F. Barker, that the American Philosophical Society shall in the near future examine into the authenticity of all the apparatus held as souvenirs in America by individuals and societies which are claimed to have been used by the founder of this Society. I must also call your attention to the claim that has been made to the effect that to Dr. Franklin and Count Rumford (Benjamin Thompson), both Americans by birth, “we owe the first important step toward a full appreciation of the co-relation of forces and the conservation of energy.” The limited acceptance as true of this im. portant fundamnental law of nature, based on the assumption that there is only a given amount of energy available in nature for man's use, and that no effort of human intelligence can add to or increase the amount of such energy at our disposal, is shown by the ready credence given even at this late day to the claims of inventors of perpetual-motion machines, or the ready ear lent to charlatans who, by means of verbose pseudo-scientific jargon and fraudulent exhibitions

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