Über die Autorin bzw. den Autor

Mark Essig earned a doctorate in American history from Cornell University. A native of St. Louis, he now lives in Los Angeles. This is his first book.

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Edison & the Electric Chair

Walker & Company

Chapter One

The ancient Greeks were the first to record the observation that amber, after being rubbed, attracted bits of straw or cloth. Around 1600 the Englishman William Gilbert noted that materials such as diamond and glass shared amber's attractive qualities. He coined a new word, electric, based on elektron, Greek for amber. An electric was a substance that, when rubbed, drew light objects to itself; electricity was the property shared by these substances.

After Gilbert the study of electricity languished for a century or so until it was taken up by members of London's Royal Society, a new association devoted to the study of the natural world. Using hollow glass tubes thirty inches long and one inch in diameter, Royal Society members produced the strongest electrical effects ever witnessed. In 1729 Stephen Gray, an experimenter with the society, corked the ends of his tube to keep dust from being sucked inside. After rubbing the glass, he noticed to his surprise that feathers were attracted to the cork as well as to the glass. The "attractive Virtue," as he put it, had been "communicated" from the glass to the cork. Curious to see how far this communication would extend, Gray attached ordinary thread to the cork, tied a shilling to the string, and found that the coin attracted feathers. He extended the string and tied on more objects-a piece of tin, an iron poker, a copper teakettle, various vegetables-and found that all became electrified. Gray attached thirty-two feet of thread to the corked end of the glass tube, tied a billiard ball to the other end of the string, and dangled it out a window. When he rubbed the glass, he found that the billiard ball still proved attractive.

Abandoning a plan to drop a string from the cupola of St. Paul's Cathedral, Gray decided to proceed horizontally. He snaked a long piece of iron wire along the ceiling of his workroom, suspending it from the beams with pieces of string. When he touched the wire with the rubbed glass wand, however, the attractive virtue did not communicate to the far end. Gray thought the string suspenders might be too thick, so he tried silk, which worked beautifully. Equally thin brass, however, failed, leading Gray to conclude that success depended upon the supports "being Silk, and not upon their being small." The differences between silk and brass wire raised the question of which objects could be supports and which receivers. (Before long another experimenter started calling these two classes conductors and insulators.) To test the electrical properties of the human body, Gray persuaded an orphan boy to allow himself to be suspended horizontally from the ceiling, supported at his chest and thighs by stout loops of silk. Gray rubbed his glass tube, touched it to the lad's feet, and found that he attracted feathers to his fingers.

Philosophers at the time believed that electricity-as well as light, heat, and magnetism-consisted of exquisitely fine "fluids" that passed through ordinary matter. The electrical phenomena of attraction and repulsion were thought to be caused by jets of subtle fluids blowing into and out of tiny pores in larger objects. The public, however, was less concerned with theories of electricity than with the thrilling effects it produced. Members of polite society in the eighteenth century flocked to scientific lecture-demonstrations, where they learned about planetary motion, the shape of the Earth, and the size of the solar system. Newtonian physics could be a bit dull, but a suspended human body attracting objects to its fingers-that was magic. Electrical displays swept Europe in the 1740s, and a French entrepreneur sold electrical kits that included a glass wand for rubbing, light objects for attracting, and thick silk cords for hanging human conductors. In darkened rooms lecturers drew sparks-"electrical fire"-from the noses of suspended men.

Experimenters in Germany produced more flamboyant effects. They replaced the glass wand with a spinning globe and used a "rubber" of leather or paper to excite it. They also suspended prime conductors-usually a sword or gun barrel-near the globe to collect the charge. Experimenters were soon killing flies with shocks from their fingers and showcasing the "Venus electrificata," a woman whose kisses threw sparks. When a glass of brandy was lifted toward the lips of a charged man, the spark from his nose set the liquor aflame.

Human conductors began to complain that these shocks were unpleasant, but they did not know true pain until they experienced another new device. In 1746 Pieter van Musschenbroek of the University of Leyden attempted to produce electricity with a glass globe and then store it in a jar of water. He attached a wire to the gun barrel that served as his prime conductor and placed the wire's end in a water-filled glass jar. While an assistant spun and rubbed the glass globe, Musschenbroek held the water jar in his hand and reached toward the gun barrel. The shock knocked him to the floor. Unwittingly, he had invented what became known as the Leyden jar, which could build up charges of remarkable strength. One experimenter used the jar to knock children off their feet, and another reported that his wife could not walk for a time after being shocked. The discharge (a new word coined to describe the Leyden jar shock) could be communicated through several people. In France, to amuse the king, a powerful Leyden jar was discharged first through a circle of 140 courtiers, then through 180 gendarmes. Two hundred Cistercians felt the jolt in their Paris monastery and leaped toward the heavens in unison. The experimenters found they could make the shocks even more powerful by linking several jars to form a battery. One man wrote, "Would it not be a Fatal surprise to the first experimenter who found a way to intensify electricity to an artificial lightning, and fell a martyr to his curiosity?"

Atmospheric lightning-the type that shot from the heavens-posed greater dangers and provoked nearly as much curiosity. According to prevailing theories, lightning resulted from colliding clouds or some unknown chemical reaction in the atmosphere, but no one knew for sure what it was. A few believed that it was composed of electrical fluid-the spark and crackle of electricity made the connection obvious-but this theory had not been proved. Inspired by an itinerant lecturer, the Philadelphia printer Benjamin Franklin began experimenting with electricity in 1745. A few years later he proposed an experiment to "determine the Question, Whether the Clouds that contain Lightning are electrified or not." He attached a silk handle to the end of a kite string and tied a key where silk and string met. Standing in a doorway to keep himself and the silk dry, he flew the kite into a "Thunder Gust." Electricity tingled down the wet string, and Franklin drew sparks from the key first with his knuckle, then with his tongue.

Many experimenters in Europe tried variations on Franklin's experiment. Most survived the dangerous test unscathed, either through dumb luck or because they carefully insulated themselves from the lightning. In 1753, however, Georg Wilhelm Richmann, a German working in St. Petersburg, drew a bolt directly through his body. He became the first man to sacrifice his life in the pursuit of...