luminiferous ether

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pages: 124 words: 40,697

The Grand Design by Stephen Hawking, Leonard Mlodinow

airport security, Albert Einstein, Albert Michelson, anthropic principle, Arthur Eddington, Buckminster Fuller, conceptual framework, cosmic microwave background, cosmological constant, dark matter, fudge factor, invention of the telescope, Isaac Newton, Johannes Kepler, John Conway, John von Neumann, luminiferous ether, Mercator projection, Richard Feynman, Stephen Hawking, Thales of Miletus, the scientific method, Turing machine

In light of such disagreements, when Maxwell claimed to have discovered the “speed of light” popping out of his equations, the natural question was, what is the speed of light in Maxwell’s equations measured relative to? There is no reason to believe that the speed parameter in Maxwell’s equations is a speed measured relative to the earth. His equations, after all, apply to the entire universe. An alternative answer that was considered for a while is that his equations specify the speed of light relative to a previously undetected medium permeating all space, called the luminiferous ether, or for short, simply the ether, which was Aristotle’s term for the substance he believed filled all of the universe outside the terrestrial sphere. This hypothetical ether would be the medium through which electromagnetic waves propagate, just as sound propagates through air. If the ether existed, there would be an absolute standard of rest (that is, rest with respect to the ether) and hence an absolute way of defining motion as well.

But Michelson’s purpose had been to measure the speed of the earth relative to the ether, not to prove or disprove the ether hypothesis, and what he found did not lead him to conclude that the ether didn’t exist. No one else drew that conclusion either. In fact, the famous physicist Sir William Thomson (Lord Kelvin) said in 1884 that the ether was “the only substance we are confident of in dynamics. One thing we are sure of, and that is the reality and substantiality of the luminiferous ether.” How can you believe in the ether despite the results of the Michelson-Morley experiment? As we’ve said often happens, people tried to save the model by contrived and ad hoc additions. Some postulated that the earth dragged the ether along with it, so we weren’t actually moving with respect to it. Dutch physicist Hendrik Antoon Lorentz and Irish physicist George Francis FitzGerald suggested that in a frame that was moving with respect to the ether, probably due to some yet-unknown mechanical effect, clocks would slow down and distances would shrink, so one would still measure light to have the same speed.


pages: 208 words: 70,860

Paradox: The Nine Greatest Enigmas in Physics by Jim Al-Khalili

Albert Einstein, Albert Michelson, anthropic principle, Arthur Eddington, butterfly effect, clockwork universe, complexity theory, dark matter, Edmond Halley, Edward Lorenz: Chaos theory, Ernest Rutherford, Henri Poincaré, invention of the telescope, Isaac Newton, Johannes Kepler, Laplace demon, luminiferous ether, Magellanic Cloud, Olbers’ paradox, Pierre-Simon Laplace, Schrödinger's Cat, Search for Extraterrestrial Intelligence, The Present Situation in Quantum Mechanics, Wilhelm Olbers

So, in the direction of travel of the car, the sound waves are moving away from it more slowly than they are moving away at right angles to it. This is because the speed at which the sound waves move ahead of the car is the difference between the speed of the waves in air and the speed of the car. Michelson and Morley applied this principle to light waves. They devised an ingenious experiment—one which they were convinced would be the first to confirm and detect the existence of the luminiferous ether. They began by assuming that the Earth is moving through the ether as it orbits the Sun, which it does at about 100,000 kilometers per hour. In their laboratory experiment they measured, with incredible accuracy, the time it took two light beams to travel along two different paths of equal distance, one in the direction of the Earth’s motion as it orbited the Sun and the other at right angles to it.

This means that there are no experiments we could perform that would tell us whether we were truly standing still or moving. The second postulate was the revolutionary one, although it sounds quite innocent at first. Einstein stated that light does indeed have the wavelike property that its speed is independent of the speed of its source (just like the sound waves from a moving car). Yet at the same time, and unlike sound waves, light does not require a medium to pass through; the luminiferous ether does not exist and light waves can move across truly empty space. So far, so good; no paradox here—and nothing, you might think, in either of these innocuous postulates that you might have difficulty subscribing to. They certainly don’t sound like statements that lead to a revolutionary view of space and time. But they do. Each postulate is, on its own, innocent. It is when the two are combined that we see how profound Einstein’s ideas were.


pages: 492 words: 149,259

Big Bang by Simon Singh

Albert Einstein, Albert Michelson, All science is either physics or stamp collecting, Andrew Wiles, anthropic principle, Arthur Eddington, Astronomia nova, Brownian motion, carbon-based life, Cepheid variable, Chance favours the prepared mind, Commentariolus, Copley Medal, cosmic abundance, cosmic microwave background, cosmological constant, cosmological principle, dark matter, Dava Sobel, Defenestration of Prague, discovery of penicillin, Dmitri Mendeleev, Edmond Halley, Edward Charles Pickering, Eratosthenes, Ernest Rutherford, Erwin Freundlich, Fellow of the Royal Society, fudge factor, Hans Lippershey, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, Henri Poincaré, horn antenna, if you see hoof prints, think horses—not zebras, Index librorum prohibitorum, invention of the telescope, Isaac Newton, Johannes Kepler, John von Neumann, Karl Jansky, Kickstarter, Louis Daguerre, Louis Pasteur, luminiferous ether, Magellanic Cloud, Murray Gell-Mann, music of the spheres, Olbers’ paradox, On the Revolutions of the Heavenly Spheres, Paul Erdős, retrograde motion, Richard Feynman, scientific mainstream, Simon Singh, Solar eclipse in 1919, Stephen Hawking, the scientific method, Thomas Kuhn: the structure of scientific revolutions, unbiased observer, Wilhelm Olbers, William of Occam

Confronted with this apparent paradox, scientists began to wonder if a vacuum was really empty. The jar had been evacuated of air, but perhaps there was something remaining inside, something that provided the medium for conveying light. By the nineteenth century, physicists had proposed that the entire universe was permeated by a substance they termed the luminiferous ether, which somehow acted as a medium for carrying light. This hypothetical substance had to possess some remarkable properties, as pointed out by the great Victorian scientist Lord Kelvin: Now what is the luminiferous ether? It is matter prodigiously less dense than air – millions and millions and millions of times less dense than air. We can form some sort of idea of its limitations. We believe it is a real thing, with great rigidity in comparison with its density: it may be made to vibrate 400 million million times per second; and yet be of such density as not to produce the slightest resistance to any body going through it.

He once nostalgically referred to the ‘beloved old ether, which is now abandoned, though I personally still cling a little to it’. The crisis of the non-existent ether was magnified because it was supposed to have been responsible for carrying both the electric and magnetic fields as well as light. The dire situation was nicely summarised by the science writer Banesh Hoffmann: First we had the luminiferous ether, Then we had the electromagnetic ether, And now we haven’t e(i)ther. So, by the end of the nineteenth century Michelson had proved that the ether did not exist. Ironically, he had built his career on a whole series of successful experiments relating to optics, but his greatest triumph was the result of a failed experiment. His goal all along had been to prove the existence of the ether, not its absence.


How Emotions Are Made: The Secret Life of the Brain by Lisa Feldman Barrett

airport security, Albert Einstein, Albert Michelson, Drosophila, en.wikipedia.org, epigenetics, framing effect, Google Glasses, Isaac Newton, longitudinal study, luminiferous ether, meta analysis, meta-analysis, phenotype, placebo effect, randomized controlled trial, Shai Danziger, Skype, Steven Pinker, the scientific method, theory of mind, Thomas Kuhn: the structure of scientific revolutions

There is no known validity to these particular facial poses, and studies that use more objective methods like facial EMG and facial coding do not find evidence that people routinely make these movements in real life during episodes of emotion. Yet scientists continue to use the basic emotion method regardless. After all, it produces very consistent results.24 Each time a scientific “fact” is overturned it leads to new avenues for discovery. The physicist Albert Michelson won a Nobel Prize in 1907 for disproving a conjecture made by Aristotle, that light travels through empty space via a hypothetical substance called luminiferous ether. His detective work set the stage for Albert Einstein’s theory of relativity. In our case, we’ve cast substantial doubt on the evidence for universal emotions. They only appear to be universal under certain conditions—when you give people a tiny bit of information about Western emotion concepts, intentionally or not. These observations, and others like them, set the stage for the new theory of emotion that you are about to learn.

They encourage us to see things that aren’t present. Firestein opens Ignorance with an old proverb, “It is very difficult to find a black cat in a dark room, especially when there is no cat.” This statement beautifully sums up the search for essences. History has many examples of scientists who searched fruitlessly for an essence because they used the wrong concept to guide their hypotheses. Firestein gives the example of luminiferous ether, a mysterious substance that was thought to fill the universe so that light would have a medium to move through. The ether was a black cat, writes Firestein, and physicists had been theorizing in a dark room, and then experimenting in it, looking for evidence of a cat that did not exist. The same applies to the classical view of emotion, whose mental organs are a human invention that mistakes the question for the answer.

“something the Fore didn’t do”: Ekman 2007, 7. a set of facial movements: Kudos to the social psychologist Robert Zajonc, who pointed out the embedded assumptions in the word “expression.” of certain Japanese emotion concepts: For examples, see heam.info/japanese-1. emotions as transactions between people: Lutz 1980; Lutz 1983. [back] 24. catalogued many of the concerns: Russell 1994. [back] 25. hypothetical substance called luminiferous ether: Firestein 2012, 22. [back] 26. in the face, body, and voice: The project began with one intrepid young psychologist, David Cordaro; see heam.info/cordaro. [back] 4. The Origin of Feeling 1. and displeasure feel qualitatively different: Pleasure and displeasure are like a sixth sense; see heam.info/pleasure-1. waking moment of your life: Every human language that has been studied has words for “feels good” and “feels bad” (Wierzbicka 1999).


pages: 257 words: 80,100

Time Travel: A History by James Gleick

Ada Lovelace, Albert Einstein, Albert Michelson, Arthur Eddington, augmented reality, butterfly effect, crowdsourcing, Doomsday Book, index card, Isaac Newton, John von Neumann, luminiferous ether, Marshall McLuhan, Norbert Wiener, pattern recognition, Richard Feynman, Schrödinger's Cat, self-driving car, Stephen Hawking, telepresence, wikimedia commons

Was the ether necessary? Or was it possible to think purely of an electrodynamics of moving bodies, through empty space? We know now that the speed of light in empty space is constant, 299,792,458 meters per second. No rocket ship can overtake a flash of light or reduce that number in the slightest. Einstein struggled (“psychic tension”; “all sorts of nervous conflicts”) to make sense of that: to discard the luminiferous ether, to accept the speed of light as absolute. Something else had to give. On a fine bright day in Bern (as he told the story later), he talked it over with his friend Michele Besso. “Next day I came back to him again and said to him, without even saying hello, ‘Thank you. I’ve completely solved the problem.’ An analysis of the concept of time was my solution.” If light speed is absolute, then time itself cannot be.


pages: 654 words: 204,260

A Short History of Nearly Everything by Bill Bryson

Albert Einstein, Albert Michelson, Alfred Russel Wallace, All science is either physics or stamp collecting, Arthur Eddington, Barry Marshall: ulcers, Brownian motion, California gold rush, Cepheid variable, clean water, Copley Medal, cosmological constant, dark matter, Dava Sobel, David Attenborough, double helix, Drosophila, Edmond Halley, Ernest Rutherford, Fellow of the Royal Society, Harvard Computers: women astronomers, Isaac Newton, James Watt: steam engine, John Harrison: Longitude, Kevin Kelly, Kuiper Belt, Louis Pasteur, luminiferous ether, Magellanic Cloud, Menlo Park, Murray Gell-Mann, out of africa, Richard Feynman, Stephen Hawking, supervolcano, Thomas Malthus, Wilhelm Olbers

There, in the 1880s, a physicist of early middle years named Albert Michelson, assisted by his friend the chemist Edward Morley, embarked on a series of experiments that produced curious and disturbing results that would have great ramifications for much of what followed. What Michelson and Morley did, without actually intending to, was undermine a longstanding belief in something called the luminiferous ether, a stable, invisible, weightless, frictionless, and unfortunately wholly imaginary medium that was thought to permeate the universe. Conceived by Descartes, embraced by Newton, and venerated by nearly everyone ever since, the ether held a position of absolute centrality in nineteenth-century physics as a way of explaining how light traveled across the emptiness of space. It was especially needed in the 1800s because light and electromagnetism were now seen as waves, which is to say types of vibrations.

At a stroke, in a simple formula, Einstein endowed geologists and astronomers with the luxury of billions of years. Above all, the special theory showed that the speed of light was constant and supreme. Nothing could overtake it. It brought light (no pun intended, exactly) to the very heart of our understanding of the nature of the universe. Not incidentally, it also solved the problem of the luminiferous ether by making it clear that it didn't exist. Einstein gave us a universe that didn't need it. Physicists as a rule are not overattentive to the pronouncements of Swiss patent office clerks, and so, despite the abundance of useful tidings, Einstein's papers attracted little notice. Having just solved several of the deepest mysteries of the universe, Einstein applied for a job as a university lecturer and was rejected, and then as a high school teacher and was rejected there as well.


pages: 285 words: 83,682

The Lies That Bind: Rethinking Identity by Kwame Anthony Appiah

affirmative action, assortative mating, Boris Johnson, British Empire, Donald Trump, Downton Abbey, European colonialism, Ferguson, Missouri, four colour theorem, full employment, illegal immigration, Isaac Newton, longitudinal study, luminiferous ether, Mahatma Gandhi, mass immigration, means of production, precariat, Scramble for Africa, selection bias, transatlantic slave trade, zero-sum game

(Tylor’s university appointments at Oxford occurred after the passage of the Universities Tests Act in 1871, which allowed people who were not Anglican to enter Oxford and Cambridge.) Indeed, it’s possible to feel that if Western culture were real, we wouldn’t spend so much time talking it up. Settling over us like a low-hanging fog, “culture,” however qualified, has been required to do a great deal of work. I admit I have sometimes wondered whether the concept of culture, like the luminiferous ether that nineteenth-century physicists posited as the medium through which light waves traveled, explains rather less than we might hope. Still, such historical and intellectual vagaries did not discourage genuinely distinguished scholars from accepting something like that Plato-to-NATO narrative. “The essence of Western culture, the basis of its success, the secret of its wide influence, is liberty,” the French political theorist Raymond Aron declared in the 1950s.


pages: 442 words: 110,704

The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars by Dava Sobel

Albert Einstein, card file, Cepheid variable, crowdsourcing, dark matter, Dava Sobel, Edmond Halley, Edward Charles Pickering, Ernest Rutherford, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, index card, invention of the telescope, Isaac Newton, Johannes Kepler, John Harrison: Longitude, luminiferous ether, Magellanic Cloud, pattern recognition, QWERTY keyboard, Ralph Waldo Emerson, Solar eclipse in 1919

Immersed now in her astronomy self-education, she found the lens for the new telescope preoccupied her as no figurine or chandelier ever had. “I bought [Charles] Young’s Elements of Astronomy,” she told Pickering, “after reading in a newspaper that it was adapted to the humblest capacity—Well there is in ‘every lowest depth a lower deep’ and I fear to fall into it. “Young calls the vast spaces between the stars a vacuum,” Miss Bruce continued, while another book she read by philosopher John Fiske “speaks of it as the luminiferous ether. I shall hold on to Young.” Pickering obligingly provided her with all the Harvard Observatory’s publications, from volumes of the Annals to offprints of his research reports. “Your paper on Variable Stars of Long Periods,” she said in a thank-you note, “I at once read and with admiration— not of the Tables but of the simple goodness of heart shown in the detailed directions to unskilled amateurs how to become useful aids to Science.”


pages: 677 words: 121,255

Giving the Devil His Due: Reflections of a Scientific Humanist by Michael Shermer

Alfred Russel Wallace, anthropic principle, anti-communist, barriers to entry, Berlin Wall, Boycotts of Israel, Chelsea Manning, clean water, clockwork universe, cognitive dissonance, Colonization of Mars, Columbine, cosmological constant, cosmological principle, creative destruction, dark matter, Donald Trump, Edward Snowden, Elon Musk, Flynn Effect, germ theory of disease, gun show loophole, Hans Rosling, hedonic treadmill, helicopter parent, hindsight bias, illegal immigration, income inequality, invisible hand, Johannes Kepler, Joseph Schumpeter, laissez-faire capitalism, Laplace demon, luminiferous ether, McMansion, means of production, mega-rich, Menlo Park, moral hazard, moral panic, More Guns, Less Crime, Peter Singer: altruism, phenotype, positional goods, race to the bottom, Richard Feynman, Ronald Coase, Silicon Valley, Skype, social intelligence, stem cell, Stephen Hawking, Steve Jobs, Steven Pinker, the scientific method, The Wealth of Nations by Adam Smith, transaction costs, WikiLeaks, working poor, Yogi Berra

According to the Caltech physicist Sean Carroll, in his 2016 book The Big Picture: On the Origins of Life, Meaning, and the Universe Itself, “All of the things you’ve ever seen or experienced in your life – objects, plants, animals, people – are made of a small number of particles, interacting with one another through a small number of forces.”14 Once you understand the fundamental laws of nature, such as the thermodynamic arrow of time and the Core Theory of particles and forces, you can scale up to planets and people, and even assess the likelihood that God, the soul, and the afterlife exist, which Carroll concludes is very low. But isn’t the history of science also strewn with the remains of failed theories like geocentrism (the Earth is the center of the solar system), phlogiston (a fire-like element that causes objects to burn), miasma (the “bad air” source of disease), spontaneous generation (fully formed living organisms can abruptly arise out of inanimate matter), and the luminiferous ether (the medium filling outer space for the propagation of light)? Yes, and that’s how we know we’re making progress. The postmodern belief that discarded ideas means that there is no objective reality and that all theories are equal is wronger than all of the wrong theories combined. I have called this Asimov’s Axiom, after an observation by the science writer Isaac Asimov: When people thought the earth was flat, they were wrong.


pages: 478 words: 131,657

Tesla: Man Out of Time by Margaret Cheney

Charles Lindbergh, dematerialisation, fudge factor, invention of radio, luminiferous ether, Menlo Park

Anyone who expects a source of power from transformation of these atoms is talking moonshine.”3 Perhaps it rankled Tesla to hear one of the “new physics” quips being attributed to Professor Sir William Bragg, co-winner of the 1915 Nobel Prize that for a time he had thought to be his. God runs electromagnetics on Monday, Wednesday, and Friday by the wave theory, said Bragg; and the devil runs it by quantum theory on Tuesday, Thursday, and Saturday. Tesla’s thoughts in later life were tending more and more toward a unifying physical theory. He believed that all matter came from a primary substance, the luminiferous ether, which filled all space, and he stoutly maintained that cosmic rays and radio waves sometimes moved more swiftly than light. The younger scientists, most of whom were affiliated with universities, were just beginning to perceive what a garden of earthly delights government-sponsored research could be. Oddly enough it was to be Edison, creator of the modern industrial research laboratory, who threw a spanner into their dreams.


pages: 478 words: 142,608

The God Delusion by Richard Dawkins

Albert Einstein, anthropic principle, Any sufficiently advanced technology is indistinguishable from magic, Ayatollah Khomeini, Brownian motion, cosmological principle, David Attenborough, Desert Island Discs, double helix, en.wikipedia.org, experimental subject, Fellow of the Royal Society, gravity well, invisible hand, John von Neumann, luminiferous ether, Menlo Park, meta analysis, meta-analysis, Murray Gell-Mann, Necker cube, Peter Singer: altruism, phenotype, placebo effect, planetary scale, Ralph Waldo Emerson, Richard Feynman, Schrödinger's Cat, scientific worldview, Search for Extraterrestrial Intelligence, stem cell, Stephen Hawking, Steven Pinker, the scientific method, theory of mind, Thorstein Veblen, trickle-down economics, unbiased observer

Steve Grand, in Creation: Life and How to Make It, is almost scathing about our preoccupation with matter itself. We have this tendency to think that only solid, material ‘things’ are ‘really’ things at all. ‘Waves’ of electromagnetic fluctuation in a vacuum seem ‘unreal’. Victorians thought that waves had to be waves ‘in’ some material medium. No such medium was known, so they invented one and named it the luminiferous ether. But we find ‘real’ matter comfortable to our understanding only because our ancestors evolved to survive in Middle World, where matter is a useful construct. On the other hand, even we Middle Worlders can see that a whirlpool is a ‘thing’ with something like the reality of a rock, even though the matter in the whirlpool is constantly changing. In a desert plain in Tanzania, in the shadow of Ol Donyo Lengai, sacred volcano of the Masai, there is a large dune made of ash from an eruption in 1969.


pages: 497 words: 146,551

Lila: An Inquiry Into Morals by Robert M. Pirsig

Albert Einstein, Buckminster Fuller, feminist movement, index card, John von Neumann, luminiferous ether, Thorstein Veblen, trade route

No evidence has been presented that if this portion of the brain is anesthetized or even lobotomized the patient will make a better scientist as a result because all his decisions will then be value-free. Yet we’re told values must reside here, if they exist at all, because where else could they be? Persons who know the history of science will recognize the sweet smell of phlogiston here and the warm glow of the luminiferous ether, two other scientific entities which were arrived at deductively and which never showed up under the microscope or anywhere else. When deduced entities are around for years and nobody finds them it is a sign that the deductions have been made from false premises; that the body of theory from which the deductions are made is wrong at some fundamental level. This is the real reason values have been avoided by empiricists in the past, not because values aren’t experienced, but because when you try to fit them into this absurd brain location you get a sinking feeling that tells you that somewhere back down the line you have gone way off the track and you just want to drop the whole subject and think about something else that has more of a future to it.


pages: 698 words: 198,203

The Stuff of Thought: Language as a Window Into Human Nature by Steven Pinker

airport security, Albert Einstein, Bob Geldof, colonial rule, conceptual framework, correlation does not imply causation, Daniel Kahneman / Amos Tversky, David Brooks, Douglas Hofstadter, en.wikipedia.org, experimental subject, fudge factor, George Santayana, Laplace demon, loss aversion, luminiferous ether, Norman Mailer, Richard Feynman, Ronald Reagan, Sapir-Whorf hypothesis, science of happiness, social intelligence, speech recognition, stem cell, Steven Pinker, Thomas Bayes, Thorstein Veblen, traffic fines, urban renewal, Yogi Berra

Many psychology experiments have shown that when people have a pet theory of how things work (such as that damp weather causes arthritis pain), they will swear that they can see those correlations in the world, even when the numbers show that the correlations don’t exist and never did.122 The habit of hallucinating causal powers and forcing experience to fit them has shaped human cultures from time immemorial, producing our species’ vast compendium of voodoo, astrology, magic, prayer, idolatry, New Age nostrums, and other flimflam. Even respectable scientists don’t stop at recording correlations but try to pry open nature’s black boxes and identify the hidden powers at work. Sometimes the candidates don’t pan out, like phlogiston or the luminiferous ether, but often they do, as with genes, atoms, and tectonic plates. Another limitation of probabilistic theories of causation is that they apply to averages over the long run (smoking causes cancer) and have nothing to say about the causes of specific events (smoking killed Granny). But people have sharp intuitions about specific events.123 Imagine that Uncle Irv, a two-pack-a-day smoker, is alive and well at ninety-seven.


pages: 782 words: 245,875

The Power Makers by Maury Klein

Albert Einstein, Albert Michelson, animal electricity, Augustin-Louis Cauchy, British Empire, business climate, invention of radio, invention of the telegraph, Isaac Newton, James Watt: steam engine, Louis Pasteur, luminiferous ether, margin call, Menlo Park, price stability, railway mania, Right to Buy, the scientific method, trade route, transcontinental railway, working poor

His second line of inquiry was experimental and resulted in nine points that summarized his own theory of electrodynamics.32 In January 1821 Ampère first introduced his notion of molecular currents, which led him to formulate a new theory of matter in which such currents were an integral part not merely of magnetism but of all molecular processes. In devising this theory he resorted to the luminiferous (“light-carrying”) ether as the agent bringing matter and electricity together. Few things baffled or divided scientists more than this mysterious substance. As described by Augustin-Jean Fresnel, a French physicist who argued that light consisted of waves, the luminiferous ether was a gaslike substance through which both light and solids somehow moved. A French mathematician, Augustin-Louis Cauchy, worked out a mathematical basis for the properties of ether that made Fresnel’s theory at least plausible if not satisfying to scientists.33 The wave theory of light required that ether be perfectly elastic and offer no resistance to a body passing through it. To these demands Ampère added a new chemical wrinkle: The ether was not simple but compound in nature and could “only be considered, in the generally adopted theory of two electric fluids, as the combination of these two fluids in that proportion in which they mutually saturate one another.”