CHAPTER XV. Account of Franklin's Electrical Discoveries. It is time, however, that we should introduce this extraordinary man to our readers in a new character. A much more important part in civil affairs than any he had yet acted was in reserve for him. He lived to attract to himself on the theatre of politics, the eyes, not of his own countrymen only, but of the whole civilized world; and to be a principal agent in the production of events as mighty in themselves, and as pregnant with mighty consequences, as any belonging to modern history. But our immediate object is to exhibit a portrait of the diligent student, and of the acute and patient philosopher. We have now to speak of Franklin's famous electrical discoveries. Of these discoveries we cannot, of course, here attempt to give any thing more than a very general account. But we shall endeavour to make our statement as intelligible as possible, even to those to whom the subject is new; referring them, for more particular information in regard to it, to the treatise on Electricity in the Library of Useful Knowledge, and the other works in which the principles of the science are formally expounded. The term electricity is derived from electron, the Greek name for amber, which was known, even in ancient times, to be capable of acquiring, by being rubbed, the curious property of attracting very light bodies, such as small bits of paper, when brought near to them. This virtue was thought to be peculiar to the substance in question, and one or two others, down to the close of the sixteenth century, when our ingenious and philosophic countryman, William Gilbert, a physician of London, announced for the first time, in his Latin treatise on the magnet, that it belonged equally to the diamond and many other precious stones; to glass, sulphur, sealing wax, rosin, and a variety of other substances. It is from this period that we are to date the birth of the science of Electricity, which, however, continued in its infancy for above a century, and could hardly, indeed, be said to consist of any thing more than a collection of unsystematized and ill understood facts, until it attracted the attention of Franklin. Among the facts, however, that had been discovered in this interval, the following were the most important. In the first place, the list of the substances capable of being excited by friction to a manifestation of electric virtue, was considerably extended. It was also found that the bodies which had been attracted by the excited substance were immediately after as forcibly repelled by it, and could not be again attracted until they had touched a third body. Other phenomena, too, besides those of attraction and repulsion, were found to take place when the body excited was one of sufficient magnitude. If any other body, not capable of being excited, such as the human hand or a rod of metal, was presented to it, a slight sound would be produced, which, if the experiment was performed in a dark room, would be accompanied with a momentary light. Lastly, it was discovered that the electric virtue might be imparted to bodies not capable of being themselves excited; by making such a body, when insulated, that is to say separated from all other bodies of the same class by the intervention of one capable of excitation, act either as the rubber of the excited body, or as the drawer of a succession of sparks from it, in the manner that has just been VOL II. 21* described. It was In consequence o bodies, and only the selves excited, might as it were, transferr conductors, as well trics, on the other ductors. It is pr should be aware, t nature, none strictly either of these clas different bodies ac influence with extre and that those wi conductors, the n mals, particularly b as resist its passag reluctance, among glass, and silk, are mination. The beginning o the annals of elect of the possibility the electric fluid, Leyden jar, or phi pened one day, v. which had been Kleist, Dean of th one hand a glass เ on a subject quite new, to me, they equally surd and pleased me. Soon after my return to delphia, our Library Company received from Peter Collinson, F.R.S. of London, a present glass tube, with some account of the use of it in such experiments. I eagerly seized the opity of repeating what I had seen at Boston; by much practice, acquired great readiness in ming those also which we had an account of England, adding a number of new ones, J way practice, for my house was continually full for time, with persons who came to see these new rs. To divide a little this incumbrance among riends, I caused a number of similar tubes to be in our glass-house, with which they furnished lves, so that we had at length several perrs. The newly discovered and extraordinary nena exhibited by the Leyden phial, of course early engaged his attention in pursuing these sting experiments; and his inquisitive mind iately set itself to work to find out the reason h strange effects, which still astonished and per 1 the ablest philosophers of Europe. Out of his lations arose the ingenious and beautiful theory action of the electric influence which is known name; and which has ever since been received "greater number of philosophers as the best, bethe simplest and most complete, demonstration phenomena, that has yet been given to the world. Franklin's earliest inquiries were directed to tain the source of the electricity which friction The effect of at least rendering manifest in the cylinder, or other electric. The question was, er this virtue was created by the friction in the ric, or only thereby communicated to it from bodies. In order to determine this point, he ted to the very simple experiment of endeavour described. It was said, in either of these cases, to be electrified; and it was found that if it was touched, or even closely approached, when in this state, by any other body, in like manner incapable of being excited by friction, a pretty loud report would take place, accompanied, if either body was susceptible of feeling, with a slight sensation of pain at the point of contact, and which would instantly restore the electrified body to its usual and natural condition. In consequence of its thus appearing that all those bodies, and only those, which could not be themselves excited, might in this manner have electricity, as it were, transferred to them, they were designated conductors, as well as non-electrics; while all electrics, on the other hand, were also called non-conductors. It is proper, however, that the reader should be aware, that of the various substances in nature, none strictly speaking, belong exclusively to either of these classes; the truth being merely, that different bodies admit the passage of the electric influence with extremely different degrees of facility, and that those which transmit it readily are called conductors, the metals, and fluids, and living animals, particularly belonging to this class; while such as resist its passage, or permit it only with extreme reluctance,―among which are amber, sulphur, wax, glass, and silk, are described by the opposite denomination. The beginning of the year 1746 is memorable in the annals of electricity for the accidental discovery of the possibility of accumulating large quantities of the electric fluid, by means of what was called the Leyden jar, or phial. M. Cuneus, of that city, happened one day, while repeating some experiments which had been originally suggested by M. Von Kleist, Dean of the Cathedral in Camin, to hold in one hand a glass vessel, nearly full of water, into |