Imponderable fluid
Encyclopedia
Imponderable fluids are features of several superseded scientific theories, such as archaic atomic
and electromotive theories
.
and physics
to explain certain mysterious phenomena as the result of fluids with properties which defy the imagination
(or at least differ from the conventional properties of fluids). The term is used in contrast with ponderable matter. Historically proposed imponderable fluids include phlogiston and caloric; additionally some physicists considered electricity
imponderable.
mentions with great disapproval a certain Nicolaas Hartsoeker who supposed that atoms moved in an ambient fluid, though the idea is not unlike his own. It is difficult to trace the origin of the hypothesis, but Galileo Galilei
and Thomas Hobbes
both speak of a subtle aether. The conception of an all-pervading imponderable fluid of this kind has formed part of many theories, and aether came to be very generally adopted as a favourite name for the fluid, but caloric was also much thought of as a medium. We even find half-a-dozen imponderable co-existent fluids regarded with favour,— one called heat
, another electricity
, another phlogiston, another light
, and what not, with little hard atoms swimming about, each endowed with forces of repulsion and attraction
of all sorts, as was thought desirable. This idea of the constitution of matter was perhaps the worst of all. These imponderable fluids were mere names, and these forces were suppositions, representing no observed fact
s. No attempt was made to show how or why the forces acted, but gravitation
being taken as due to a mere "force
", speculators thought themselves at liberty to imagine any number of forces, attractive or repulsive
, or alternating
, varying as the distance
, or the square
, cube, or higher power of the distance
, etc. At las Ruđer Bošković got rid of atoms altogether, by supposing them to be the mere centre of forces
exerted by a position or point only, where nothing existed but the power of exerting a force.
.
M. Martin Ziegler patented a method of producing a "vital fluid" by combining nitrogen and carbon in a porous cell containing ammonia, immersed in a vessel tilled with molasses. The current was to flow through silk threads attached to the vessel: about 1868.
Atomic theory
In chemistry and physics, atomic theory is a theory of the nature of matter, which states that matter is composed of discrete units called atoms, as opposed to the obsolete notion that matter could be divided into any arbitrarily small quantity...
and electromotive theories
Electromotive force
In physics, electromotive force, emf , or electromotance refers to voltage generated by a battery or by the magnetic force according to Faraday's Law, which states that a time varying magnetic field will induce an electric current.It is important to note that the electromotive "force" is not a...
.
Description
The term has been used in natural philosophyNatural philosophy
Natural philosophy or the philosophy of nature , is a term applied to the study of nature and the physical universe that was dominant before the development of modern science...
and physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
to explain certain mysterious phenomena as the result of fluids with properties which defy the imagination
Imagination
Imagination, also called the faculty of imagining, is the ability of forming mental images, sensations and concepts, in a moment when they are not perceived through sight, hearing or other senses...
(or at least differ from the conventional properties of fluids). The term is used in contrast with ponderable matter. Historically proposed imponderable fluids include phlogiston and caloric; additionally some physicists considered electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
imponderable.
Fluids theories
Gottfried LeibnizGottfried Leibniz
Gottfried Wilhelm Leibniz was a German philosopher and mathematician. He wrote in different languages, primarily in Latin , French and German ....
mentions with great disapproval a certain Nicolaas Hartsoeker who supposed that atoms moved in an ambient fluid, though the idea is not unlike his own. It is difficult to trace the origin of the hypothesis, but Galileo Galilei
Galileo Galilei
Galileo Galilei , was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism...
and Thomas Hobbes
Thomas Hobbes
Thomas Hobbes of Malmesbury , in some older texts Thomas Hobbs of Malmsbury, was an English philosopher, best known today for his work on political philosophy...
both speak of a subtle aether. The conception of an all-pervading imponderable fluid of this kind has formed part of many theories, and aether came to be very generally adopted as a favourite name for the fluid, but caloric was also much thought of as a medium. We even find half-a-dozen imponderable co-existent fluids regarded with favour,— one called heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
, another electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
, another phlogiston, another light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
, and what not, with little hard atoms swimming about, each endowed with forces of repulsion and attraction
Intermolecular force
Intermolecular forces are forces of attraction or repulsion which act between neighboring particles: atoms, molecules or ions. They are weak compared to the intramolecular forces, the forces which keep a molecule together...
of all sorts, as was thought desirable. This idea of the constitution of matter was perhaps the worst of all. These imponderable fluids were mere names, and these forces were suppositions, representing no observed fact
Empirical
The word empirical denotes information gained by means of observation or experimentation. Empirical data are data produced by an experiment or observation....
s. No attempt was made to show how or why the forces acted, but gravitation
Gravitation
Gravitation, or gravity, is a natural phenomenon by which physical bodies attract with a force proportional to their mass. Gravitation is most familiar as the agent that gives weight to objects with mass and causes them to fall to the ground when dropped...
being taken as due to a mere "force
Force
In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity , i.e., to accelerate, or which can cause a flexible object to deform...
", speculators thought themselves at liberty to imagine any number of forces, attractive or repulsive
Magnetism
Magnetism is a property of materials that respond at an atomic or subatomic level to an applied magnetic field. Ferromagnetism is the strongest and most familiar type of magnetism. It is responsible for the behavior of permanent magnets, which produce their own persistent magnetic fields, as well...
, or alternating
Alternating current
In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
, varying as the distance
Waveform
Waveform means the shape and form of a signal such as a wave moving in a physical medium or an abstract representation.In many cases the medium in which the wave is being propagated does not permit a direct visual image of the form. In these cases, the term 'waveform' refers to the shape of a graph...
, or the square
Square root
In mathematics, a square root of a number x is a number r such that r2 = x, or, in other words, a number r whose square is x...
, cube, or higher power of the distance
Nth root
In mathematics, the nth root of a number x is a number r which, when raised to the power of n, equals xr^n = x,where n is the degree of the root...
, etc. At las Ruđer Bošković got rid of atoms altogether, by supposing them to be the mere centre of forces
Point (geometry)
In geometry, topology and related branches of mathematics a spatial point is a primitive notion upon which other concepts may be defined. In geometry, points are zero-dimensional; i.e., they do not have volume, area, length, or any other higher-dimensional analogue. In branches of mathematics...
exerted by a position or point only, where nothing existed but the power of exerting a force.
The electric fluid
Study of the laws which govern electrical forces, let an apparatus be provided, called an electric pendulum. Effects were explained by the supposition that a subtle and imponderable fluid developed upon the glass tube which is self-repulsive; that by touching the balls, a portion of this fluid has been imparted to them, which is diffused over their surface, and which, for reasons that will hereafter appear, cannot escape by the thread of suspension; that the fluid remaining on the glass tube repels this fluid diffused on the balls, and therefore repels the balls themselves which are invested by the fluid; and, in fine, that the fluid diffused on the one ball repels and is repelled by the fluid diffused on the other ball, and that the balls being covered by the fluid are reciprocally repelled. A vast body of phenomena had converted this supposition into a certainty for the time, accepted by all scientific authorities. The fluid producing these effects was called the "Electric Fluid", now called the electric fieldElectric field
In physics, an electric field surrounds electrically charged particles and time-varying magnetic fields. The electric field depicts the force exerted on other electrically charged objects by the electrically charged particle the field is surrounding...
.
M. Martin Ziegler patented a method of producing a "vital fluid" by combining nitrogen and carbon in a porous cell containing ammonia, immersed in a vessel tilled with molasses. The current was to flow through silk threads attached to the vessel: about 1868.
Further reading
- Grove, W. R. (1874). The correlation of physical forces. London: Longmans, Green.
- Priestley, J. (1767). The history and present state of electricity: With original experiments, by Joseph Priestley. London.
- Grotthus, "Sur la Composition de l'Eau et des Corps quelle tient en dissolution a l'aide de l'Electricite galvanique". (Tr., On the Composition of Water Bodies and what holds in solution with the aid of galvanic electricity.)