Principles of electricity

Many persons who have devoted no time to the study of physics wonder what the force is that drives the street-car along—turning its wheels, while at the same time furnishing incandescent lamps (light) for the passengers. They have been told, of course, that the “power” used is “electricity”, generated by dynamos “at the power-house”, and conveyed to the rapidly moving car by the overhead wire.

“Electricity: yes, but what is electricity?” This is a natural and perfectly legitimate question for a layman to ask.

Scientists and philosophers are asking the same question. But they understand quite well that it is like asking: “What is matter?” Very probably the average inquirer does not ask the question, “What is electricity?” in the same spirit. We can answer one question no better than the other, if the ultimate nature of either matter or electricity is what the inquirer has in mind.

For matter, in the last analysis, is electricity. Yet the same person who might ask: “What is electricity?” would not think of asking: “What is matter?” He thinks he knows what matter is—his common sense tells him that matter is what it appears to be. “Matter’s matter, and there’s an end of it.”

And just so the physicist insists upon his common-sense right to reply: “Electricity is electricity.” It is what it appears to him to be. And it appears to be a form of energy, or a mode of motion.

Thales, the reputed founder of Greek science and philosophy, would call electricity “the soul of the universe”, because it “endows all things with motion”. This “soul”, interpenetrating all matter—if not constituting it—is by nature always moving—it is self-moving; motion is part of its very essence. In the lodestone, said Thales, “it moves iron.”[1]

As has been said so many times before, Thales was the first to call attention to the fact that amber (fossilized resin), when rubbed with wool or fur, possesses the curious property of attracting small particles, such as straw, pith, lint, dried leaves, etc.;—though there is no reason to suppose that he was the discoverer of this phenomenon. He called the amber elektron; and today we call the indivisible corpuscles, or natural unit charges of negative electricity, electrons—the true atoms of electricity.

But hard rubber, or sealing-wax, is just as “mysterious” as the lodestone (magnetite—natural magnetic iron). Rub the sealing-wax with fur, and it will exhibit all the peculiar properties of the lodestone. Rub glass with silk, and it, too, becomes a lodestone in effect. The ancient Greek philosophers could not explain these phenomena in precise terms.

Empedocles (born between 500 and 480 B. C.) accounted for the attraction of iron to the magnet on the hypothesis that “emanations” or “effluences” from the magnet penetrate into the “symmetrical pores” of the iron, drawing the iron itself and holding it fast. The concept “electricity” was unknown to the Greeks. But it is possible that Empedocles had in mind some such “effluence” or “emanation” as the “fluid” electricity of Benjamin Franklin (1706-1790) and his successors.

The soul-force (“moving power”) of Thales—always moving and causing movement—and the “effluences” of Empedocles have become the “field of force” of Faraday, Sir J. J. Thomson, and Sir Oliver Lodge. The self-moving “soul” of nature, manifest in the lodestone, or acting on the lodestone, or on the particles said to be “attracted” by the lodestone, is but a synonym for the lines of force of the magnetic field of modern physics. Thales and Empedocles spoke in the language (terminology) of their day and age. The “emanations” of Empedocles are the “corpuscles” of Thomson—a body becoming positively electrified by “losing some of its corpuscles”, and hence capable of drawing negatively charged particles to itself.

Electricity and magnetism are related but not identical. A moving magnet can induce an electric current in a wire, and an electric current can produce magnetism in iron. The construction of telegraph and telephone instruments depends on the fact that an electric current can produce magnetism and that magnetism can produce an electric current.

We know effects which we call “electricity”, just as we know the phenomena associated with living protoplasm without knowing what “life” is. It may be that “life” and “electricity”, as well as “electricity” and “magnetism”, are all different aspects of the same thing.

Today we say, in the words of Dr. Charles P. Steinmetz (“Relativity and Space”, Pages 18-19):—

“The space surrounding a magnet is a magnetic field. If we electrify a piece of sealing-wax by rubbing it, it surrounds itself by a dielectric or electrostatic field, and bodies susceptible to electrostatic forces—such as light pieces of paper—are attracted. The earth is surrounded by a gravitational field, the lines of gravitational force issuing radially from the earth. If a stone falls to the earth, it is due to the stone’s being in the gravitational field of the earth and being acted upon by it.”

Again:—“Suppose we have a permanent bar magnet and bring a piece of iron near it. It is attracted, or moved; that is, a force is exerted on it. We bring a piece of copper near the magnet, and nothing happens. We say that the space surrounding the magnet is a magnetic field. A field, or field of force, we define as ‘a condition in space exerting a force on a body susceptible to this field’. Thus, a piece of iron being magnetizable—that is, susceptible to a magnetic field—will be acted upon; a piece of copper, not being magnetizable, shows no action.... To produce a field of force requires energy, and this energy is stored in the space we call the field. Thus we can go further and define the field as ‘a condition of energy storage in space exerting a force on a body susceptible to this energy’.”

Thales said that the “divine moving power”, the soul of nature, under certain conditions “moves iron”, through the mysterious properties of the lodestone. Modern science, borrowing from Aristotle the term energia, substitutes for “soul of nature” the single word energy. Aristotle declared that “not capacity, but energy ... is the first principle anterior to and superior to anything else” (Metaphysics xii, 7: cf. also Physics ii, 9, 6).

Modern science describes in more precise phrases what occurs when a body susceptible to the influence of the magnet is brought into proximity to a lodestone (magnetite). It gives us a picture of “lines of force” (energy) in a defined “field”. But it tells us no more about what energy is than Thales tells us what his “moving power” is. Dr. Steinmetz tells us that “energy is the only real existing entity, the primary conception, which exists for us because our senses respond to it” (Op. cit., Page 23). For Thales the universal “moving power” of nature operates on or in all matter; for the physicist of today the moving power (energy) is matter—man’s perception of matter being the response of his senses to the vibrations of energy. “All sense perceptions are exclusively energy effects,” and “energy is the only real existing entity.”

Thales may or may not have considered the cosmos as “matter” and “soul” or “moving power”. In any event the pre-Socratic Ionian philosophers recognized no distinction between matter and soul in our modern sense. The moving power of nature (soul) was as much a material substance as gross matter itself, only more rarefied, more elusive. It was equivalent to the “energy”—electricity—of modern science.

Here we have, then, the answer to the question: “What is electricity?” It is energy—“the only real existing entity, the primary conception, which exists for us because our senses respond to it.” “All sense perceptions are exclusively energy effects.” This is the answer to the question: “What are the Hertzian waves, used in ‘wireless’?” It is the answer also to the question: “What is light?” as well as “What is electricity?” By carrying the explanation of the beam of light and the electromagnetic wave (like that of the radio communication station or that surrounding a power transmission line) back to the energy field (or, less accurately, the field of force), we have carried it back, as Dr. Steinmetz well declared, as far as possible, “to the fundamental or primary conceptions of the human mind, the perceptions of the senses.”

All that we know of the world is derived from the perceptions of our senses, which are for us the only real facts, all things else being conclusions from them; and “all sense perceptions are exclusively energy effects.” Electricity is an energy effect, perceived by our senses. No other definition or explanation can or need be given, since energy is the primary conception. And this explains also what matter is, since energy and matter are interchangeable—or equivalent—terms. What we call electricity is one of the effects of energy on our senses. In itself, it is energy, the stuff that matter is made of; at once the “moving power” and the thing moved.

Everything has been said that can be said now as to what electricity is: our concern in the remainder of this volume will be to discover what electricity does and how it acts.

The reader of this little book who may be more or less familiar with larger volumes dealing with electricity, energy, electrons, electromagnetic waves or oscillations, magnetic and dielectric fields (usually combined), light-waves, etc., will notice that no mention has been made of the classical ether hypothesis, the universal plenum in which energy is said to be stored, and in which transverse waves of light are said to occur, ether atoms or vibrations moving at right angles (perpendicularly) to the light-beam.

Now, transverse waves can exist only in rigid (solid) bodies. The universal ether of space, referred to in the text-books, must—for reasons which I need not discuss here—be a solid body of a rigidity much greater than that of steel, while at the same time possessing a very great elasticity so that bodies (such as the planets) moving through it meet with no resistance, no friction. The electron theory of Lorentz, Larmor, Thomson, Lodge and others is based upon the assumption that such a plenum, or medium, is a real substance. As a matter of fact, it is not known that any such medium (or ether) does exist, and it is now recognized that while light is a wave, a periodic phenomenon, like an alternating current, it is not necessarily a wave motion of something or in something, any more than it is necessary to assume the alternating current or voltage wave to be a motion of matter.

Electrical engineers make no assumption regarding the existence of an ether filling all space and interpenetrating all matter—have no need for an ether as the hypothetical carrier of the electric wave. And just so the physicist of today has no real need for the classical assumption that the light-wave is a wave motion of or in something of great rigidity yet highly elastic and frictionless, filling all space. Light is now known to be a high-frequency electromagnetic wave, and cannot logically be considered as a wave motion of a hypothetical ether. “The ether thus vanishes, following the phlogistin and other antiquated conceptions.”[2] As Prof. A. S. Eddington remarks in his “Report on the Relativity Theory of Gravitation” (1920), “Light does not cause electromagnetic oscillations; it is the oscillations.”

We know nothing whatever about the so-called ether of space; but we can formulate very clearly “The Principles of Electricity” without the aid of that hypothesis.[3]