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THE DAWN OF ELECTRICITY.

THERE lies, at this writing, before me a Latin translation of the "Lives of the Philosophers," by Diogenes Laertius, bearing on its colophon the imprint of Octavianus Scotus, Venice, and the date of 1490. It contains, among other memoirs, the life of Thales of Miletus, one of the so-called seven wise men of Greece, and there appear, in the curious characters of the early printers, two lines which, freely translated, read thus:

"But Aristotle and Hippias say that he attributed souls also to lifeless things, forming his conjecture from the nature of the magnet and of amber.”

Thales lived six hundred years before the Christian era; and while he was not the first to observe the attractive quality either of the magnet or of amber, for he learned the fact from the Egyptians, he at least invented the general theory of the "souls in lifeless things," and of the "amber soul" in particular. The sentence which I have quoted, however, relates both to the fact that the magnet and the amber will attract light bodies, and to the only theory extant to account for the peculiarity of amber; and thus it may be said fairly to represent all the knowledge of this strange phenomenon which the world possessed at the time of Thales, and to which, so far as related to the amber, nothing was added during the twenty centuries following.

There is some evidence that the ancients knew that a certain stone termed the "lyncurium," and supposed to be either the hyacinth or the tourmaline, would, when heated, behave like amber; but the old writings are contradictory and conjectural, and the phenomena described do not, in many respects, tally with the results of modern observation. So also, at some period, jet was found to act similarly to amber when rubbed; but how or when this was discovered, or, indeed, whether jet, often called "black amber," was not generically included in the "electrum" or "succinum" of the early writers, may be open to discussion.

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It is important to distinguish between the knowledge of the ancients concerning natural phenomena which we now know to be electrical, and their acquaintance with the magnet and with amber-a source apparently of much confusion in the minds of many historians of electricity. There are countless traditions based on the lightning stroke, many of them as fantastic as ever romancer conceived. Tullus Hostilius is reputed to have been killed while essaying the role of Franklin, although Numa Pompilius, before him, is asserted already to have invented the lightning-rod. Earlier still, Prometheus is said to have brought down the electrical fire. There are writers who claim that the temple of Jerusalem was as well provided with lightning-rods as any modern building, and that a temple of Apollo was equally well protected by its encompassing laurels; that one Porsenna anticipated the modern idea of execution by electricity, by conducting the lightning to the territory of Volsinium, and there, by its aid, killing a devastating monster; that the vestal fire was kindled by lightning; that Moses was an electrician and another prototype of Franklin; and when we reach the dense ignorance of the dark ages, these and other like stories assume such prodigious and multiplied shapes that one wonders how the small modicum of truth which has formed the foundation of the present great science escaped being hopelessly crushed out of existence.

So, also, a distinction must be drawn between what was known in ancient times concerning the properties of the loadstone and what was known about the properties of rubbed amber. The ancients assumed that a like demon produced like effects in both. Here, again, modern writers have erred by ascribing to them knowledge of the correlation or interconvertibility of electricity and magnetism, forgetting that this was brought to light only by the discoveries of Arago and Faraday during the present century. The electrical knowledge of antiquity was restricted to the phenomenon presented by rubbed amber, and the theory of the amber soul proposed to explain it; but this, albeit the merest spark, maintained its existence for two thousand years before the breath of genius kindled it to flame.

The Venetian edition of the Greek historian grew ancient. In course of nature all men living when it came from the press

passed away. Still this same sentence continued to represent the sum of human learning in the science, and the unthought-of generation found itself no wiser, and, concerning the strange soul hidden in the yellow depths of the amber, speculating as hopelessly as the forgotten dust in its graveyards had done a century before. But then the times had changed, and with them the whole drift of human thought and activity. The reign of Elizabeth in England was drawing to its close. The menacing specter of the Spanish invasion, vanishing amid the wreck of the Armada, had left the people free to turn to other things than war and statecraft; to think, in fact, of themselves and for themselves. The liberated energy was manifesting itself on every side. The restless adventurers of Britain were penetrating unknown regions and circumnavigating the globe itself. From the realms of fancy English poets were bringing forth all-surpassing treasure. English philosophy, for the infinitely attenuated virus of theory and speculation which had permeated the schools down through generation after generation, was about to substitute the questioning of nature, to replace the "philosophy of words" with the "philosophy of works."

But "Franciscus Bacon sic cogitavit," had not yet been said. The last year of the sixteenth century had seen the gallant, vain, and foolish Essex hounded to his death by the eloquence of the advocate whom he had rescued from penury and the sponginghouses of Conduit Street; but the hand which penned the labored apology for that shameless work did not write the "De Augmentis" until half a decade later. It is said that remorse following upon the death of Essex hastened in the queen the beginning of that slow physical decadence which ended her life. If so, then, looking back upon this episode and upon the great actors who took part in it, we can dimly discern among them the presence of another player, albeit he stands in the shadow and we do not hear his voice. But his hand is on the failing pulse of the queen; he cautions against the excesses of the royal progress; he mingles the potion that fills the golden cup, which, the chronicler saith, she often put to her lips; he stands gravely silent, powerless to check the inroads of the "strange melancholy which beset her; and when that life "so great, so strange

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and lonely in its greatness, passed quietly away," William Gilbert, wise and faithful physician, turned from that bedside, broken-hearted, and went home to die.

This was the man who created the modern science of electricity, and gave to it "a local habitation and a name."

William Gilbert was born in the year 1540, in the parish of Colchester, and "was accounted the chief person thereof." He was educated at Cambridge, gained a fellowship, made the grand tour, and returned to England a doctor in medicine, having obtained his degree from a foreign university. He became a member and finally President of the Royal College of Physicians in London, in which city he taught and practiced his profession for some thirty years, achieving such eminence that the queen appointed him her physician. "Such his loyalty to the queen," says old Thomas Fuller, "that as if unwilling to survive her he died in the same year with her, 1603;" and the same writer lovingly speaks of him as having "the clearness of Venice glass without the brittleness thereof, soon ripe and long lasting in his perfections."

In the year 1600 was published Gilbert's great treatise, "De Magnete, Magneticisque Corporibus, et de Magno Magnete Tellure: Physiologia Nova Plurimis et Argumentis et Experimentis Demonstrata." If titles are to be indicative of contents, never had book an apter title, nor one better calculated to excite the keenest curiosity. Never before had "magnetic bodies," nor that "great magnet the earth," been heard of; never before had "experiments" been appealed to as the sole basis for a new physiology. It was the blast of the trumpet before the walls of the Jericho of second-hand philosophy, and they tottered and crumbled before it. "Facile est hominibus ingenio acutis absque experimentis et usu rerum labi et errare," he says. His object is "to arrange facts founded on trials of the properties of natural things, to give to my subject demonstrations similar to those adopted in geometry, which, on the most simple foundation, raises the most magnificent works."

The Platonists, who taught that geometry was degraded when

applied to purposes of vulgar utility, were not slow in recogniz ing the affront. But Gilbert's quarry was no sect; he blazed hostility at the whole ruck of scholastic hair-splitters. "I renounce all subtleties connected with letters. I depend upon things which may be made evident to the senses, things which may be easily tried," he says; and then again and again he pours out invective upon those who "stuffed the booksellers' shops by copying from one another extravagant stories concerning the attraction of magnets and amber, without giving any reason from experiment," and upon the philosophers “in tenebris somniantes," in a way that makes the later thunder of the Baconian Jove sound like mere echo.

For nineteen years Gilbert had been at work. Never before were the tidings of such great discoveries crowded into so few pages, or told in terser or more vigorous Latin. There is a preface, an address to the author, seemingly by one of his pupils, and then a page devoted to the "interpretation of certain words." I reproduce from this page one line:

Electrica, quæ attrahunt eadem ratione vt electrum.

This is the first mention of the word "electric," and thus the father of the science christened it.

The whole work is divided into six books, and it sets forth nearly every fundamental fact upon which our present knowledge of magnetic phenomena depends. It announces the discovery of the magnetic poles and of the neutral space between them, and the great generalization that like magnetic poles repel, while unlike magnetic poles mutually attract. It draws the distinction between magnets which have poles, and magnetic bodies, such as iron, which have no poles, but which will attract either pole of the magnet. It declares that the earth itself is a huge magnet, which causes the compass needle to assume its north and south position; which magnetizes iron bars placed upright for a considerable time, or hammered while held in the magnetic meridian; or which converts steel bars into magnets when they are cooled standing parallel to the same meridian after being heated red hot. It announces the properties of the armature or

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