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When, in his “Midsummer Night’s Dream,” Shakespeare placed in the mouth of Puck, prince of fairies, the playful speech,—

“I’ll put a girdle round about the earth

In forty minutes,”

he had no thought that the undertaking of a boastful and prankish sprite could ever be outdone by human agency. Could the immortal bard have lived to witness the time when the girdling of the earth by means of the electric current became easier and swifter than elfin promise or possibility, he must have speedily remodeled his splendid comedy and denied to the world its delightful, fairy-like features.

An old and charming story runs, that Aladdin, son of a widow of Bagdad, became owner of a magic lamp, by means of whose remarkable powers he could bring to his instant aid the services of an all-helpful genie. When Aladdin wished for aid of any kind, he had but to rub the lamp. At once the genie appeared to gratify his desires. By means of the lamp Aladdin could hear the faintest whisper thousands of miles away. He could annihilate both time and space, and in a twinkling could transfer himself to the tops of the highest mountains. How the charm of this ancient story is lost in the presence of that marvelous realism which marks the achievements of modern electrical science!

The earliest known observations on that subtle mystery which pervades all nature, that silent energy whose phenomena and possibilities are limitless, and before which even the wisest must stand in awe, are attributed to Thales, a scholar of Miletus, in Greece, some 600 years B.C. On rubbing a piece of amber against his clothing, he observed that it gained the strange property of at first attracting and then repelling light objects brought near to it. His observations led to nothing practical, and no historic mention of electrical phenomena is found till the time of Theophrastus (B.C. 341), who wrote that amber, when rubbed, attracted “straws, small sticks, and even thin pieces of copper and iron.” Both Aristotle and Pliny speak of the electric eel as having power to benumb animals with which it comes in contact.

Thus far these simple phenomena only had been mentioned. There was no study of electric force, no recognition of it as such, or as we know it and turn it to practical account to-day. This seems quite strange when we consider the culture and power to investigate of the Egyptians, Phœnicians, Greeks, and Romans. True, a few fairy-like stories of how certain persons emitted sparks from their bodies, or were cured of diseases by shocks from electric eels, are found scattered through their literatures, but they failed to follow the way to electrical science pointed out to them by Thales. Even in the Middle Ages, when a few scientists and writers saw fit to speak of electrical phenomena as observed by the ancients, and even ventured to speculate upon them in their crude way, there were no practical additions made to the science, and the ground laid as fallow as it had done since the creation.

OLD FRANKLIN ELECTRICAL MACHINE.

(By permission of Franklin Institute.)

After a lapse of more than two thousand years from the experiment of Thales, Dr. Gilbert, physician to Queen Elizabeth (A.D. 1533–1603), took up the study of amber and various other substances which, when subjected to friction, acquired the property of first, attracting and then repelling light bodies brought near them. He published his observations in a little book called “De Magnete,” in the year A.D. 1600, and thus became the first author of a work upon electricity. In this unique and initial work upon simple electrical effects, the author added greatly to the number of substances that could be electrified by friction, and succeeded in establishing the different degrees of force with which they could be made to attract or repel light bodies brought near them.

Fortunately for electrical science, and for that matter all sciences, about this time the influence of Lord Bacon’s Inductive Philosophy began to be felt by investigators and scientific men. Before that, the causes of natural phenomena had not been backed up by repeated experiments amounting to practical proofs, but had been accounted for, if at all, by sheer guesses or whimsical reasons. Bacon’s method introduced hard, cold, constant experiment as the only sure means of finding out exactly the causes of natural phenomena; and not only this, but the necessity of series upon series of experiments, each based upon the results of the former, and so continuing, link by link, till, from a comparison of the whole, some general principle or truth could be drawn that applied to all. This inductive method of scientific research gave great impetus to the study of every branch of science, and especially to the unfolding of infallible and practical laws governing the phenomena of nature.

For very many years electrical experiments followed the lines laid down by Dr. Gilbert; that is, the finding of substances that could be excited or electrified by friction. By and by such substances came to be called electrics, and it became a part of the crude electrical science of the time to compute the force with which these electrics, when excited, attracted or repelled other substances near them. Among the ablest of these investigators were Robert Boyle, author of “Experiments on the Origin of Electricity,” Sir Isaac Newton, Otto von Guericke, and Francis Hawksbee, the last of whom communicated his experiments to the English Royal Society in 1705. Otto von Guericke used a hard roll of sulphur as an electric. He caused it to revolve rapidly while he rubbed or excited it with his hand. Newton and Hawksbee used a revolving glass globe in the same way, and thus became the parents of the modern and better equipped electrical machine used for school purposes.

The next step in electrical discovery, and one which marks an epoch in the history of the science, was made by Stephen Gray, of England, in 1729. To him is due the credit of finding out that electricity from an excited glass cylinder could be conducted away from it to objects at a remote distance. Though he used only a packthread as a conductor, he thus carried electricity to a distance of several hundred feet, and his novel discovery opened up what, for the time, was a brilliant series of experiments in England and throughout France and Germany. Out of these experiments came the knowledge that some substances were natural conductors of electricity, while others were non-conductors; and that the non-conductors were the very substances—glass, resin, sulphur, etc.—which were then in popular use as electrics. Here was laid the foundation of those after-discoveries which led to the selection of copper, iron, and other metals as the natural and therefore best conductors of electricity, and glass, etc., as the best insulators or non-conductors.

Up to this time an excited electric, such as a glass cylinder or wheel, had furnished the only source whence electricity had been drawn for purposes of experiment. But now another great step forward was taken by the momentous discovery that electricity, as furnished by the excited but quickly exhausted electric, could be bottled up, as it were, and so accumulated and preserved in large quantities, to be drawn upon when needed for experiment. It is not known who made this important discovery; but by common consent the storage apparatus, which was to play so conspicuous a part in after-investigations, was named the Leyden Jar or Phial, from the city of Leyden in Holland. It consisted of a simple glass jar lined inside and out with tinfoil to within an inch or two of the top, the tinfoil of the inside being connected by a conductor passing up through the stopper of the jar to a metallic knob on top. This jar could be charged or filled with electricity from a common electric, and it had the power of retaining the charge till the knob on top was touched by the knuckle, or some unelectrified substance, when a spark ensued, and the jar was said to be discharged. By conductors attached to the knob, guns were fired off at a distance by means of the spark, and it is said that Dr. Benjamin Franklin ignited a glass of brandy at the house of a friend by means of a wire attached to a Leyden jar and stretched the full width of the Schuylkill River at Philadelphia.

LEYDEN JAR.

At this stage in the history of eighteenth century electricity there enters a character whose experiments in electricity, and whose writings upon the subject, not only brought him great renown at home and abroad, but perhaps did more to systematize the science and turn it to practical account than those of any contemporary. This was the celebrated Dr. Benjamin Franklin, of Philadelphia, Pa. He showed to the world that electricity was not created by friction upon an electric, but that it was merely gathered there, when friction was applied, from surrounding nature; and in proof of his theory he invaded the clouds with a kite during a thunder-storm, and brought down electricity therefrom by means of the kite-string as a conductor. The key he hung on the string became charged with the electric fluid, and on being touched by an unelectrified body, emitted sparks and produced all the effects commonly witnessed in the discharge of the Leyden jar.

Franklin further established the difference between positive and negative electricity, and showed that the spark phenomenon on the discharge of the Leyden jar was due to the fact that the inside tinfoil was positively electrified and the outside tinfoil negatively. When the inside tinfoil was suddenly drawn upon by a conductor, the spark was simply the result of an effort upon the part of the two kinds of electricity to maintain an equilibrium. By similar reasoning he accounted for the phenomenon of lightning in the clouds, and by easy steps invented the lightning-rod, as a means of breaking the force of the descending bolt, and carrying the dangerous fluid safely to the ground. Here we have not only a practical result growing out of electrical experiments, but we witness the dawn of an era when electricity was to be turned to profitable commercial account. The lightning-rod man has been abroad in the world ever since the days of Franklin.

Thus far, then, electrical science, if science it could yet be called, had gotten on at the dawn of the nineteenth century. No electricity was really known but that produced by friction upon glass, or some other convenient electric. Hence it was called frictional electricity by some, and static electricity by others, because it was regarded as electricity in a state of rest. Though a thing fitted for curious experiment, and a constant invitation to scientific research, it had no use whatever in the arts. An excited electric could furnish but a trivial and temporary supply of electricity. It exhausted itself in the exhibition of a single spark.