Molecular motion

“ While the molecules as wholes increase one another’s oscillations, or derange one another’s oscillations, or both, the components of them cannot be so stably arranged that members of the one group are wholly inoperative on members of the other group. And if they are operative, then there must be a compound form of molecular motion which arises when masses of highly-compounded molecules of unlike kinds, are made to act on one another. ”

“ By such an assumption the molar motion perceived by vision would be legitimately derived from the molecular motion known by higher reason, and appear as a change of direction in the molecular motions of the ball. No motion as speed would be created or destroyed, while the apparent molar motion would be explained by a change of direction in molecular motions, very minute as compared with the composite paths of the several molecules and atoms. ”

“ It is imagined that the molecular motions representing temperature, chemical affinity, electrification, or other energy, coexist without confusion, just as air sustains, in perfect order, the superposed harmonies of an orchestra and chorus. The extremely rapid motion of molecules, acting at their comparatively vast surfaces, must immensely exalt forces which, between masses, are but feeble. ”

“ We have proof by our senses of the existence of molecular movement among the particles of all heated bodies; while we have no similar experience in the case of light. When, therefore, heat is communicated from the sun to the earth across apparently empty space, the chain of causation has molecular motion both at the beginning and end. The hypothesis only makes the motion continuous by extending it to the middle. Now, motion in a body is known to be capable of being imparted to another body contiguous to it ”

“ In molecular bodies motions are correlated in a manner yet unknown, but molecules are known to have interior motions exhibited in response to motions in the ether as its particles impinge on ponderable matter. The correlated structural motions of the molecule may be transmuted by collision with ethereal particles and be converted into heat—a mode of motion—so that which is structural motion will appear as heat, and if the transmutation is carried to a sufficient degree the structure of a molecular body will be destroyed, for by heat molecules are reduced to lower molecules or to atoms. ”

“ That a particular molecular motion does give rise to a state of consciousness is experimentally certain; but the how and why of the process are just as inexplicable as in the case of the communication of kinetic energy by impact. ”

“ It is now believed, and to a large extent demonstrated, that the force, apparently lost, has been transformed into heat, electricity, or some other kind of molecular motion, of which the change of shape is only the outward sign. The establishment on a firm foundation of theory and experiment of the so-called conservation of energy, the child of the correlation of physical forces, is one of the first fruits of molecular mechanics. ”

“ That motion of masses produced during Evolution, is being slowly re-diffused in molecular motion of the ethereal medium; both through the progressive integration of each mass, and the resistance to its motion through space. Infinitely remote as may be the state when all the motions of masses shall be transformed into molecular motion, and all the molecular motion equilibrated; yet such a state of complete integration and complete equilibration, is that towards which the changes now going on throughout the Solar System inevitably tend. ”

“ We may dimly perceive that if portions of what was originally a uniform mass having a common function, undertake subdivisions of the function, the molecular changes going on in them will be in some way complementary to one another: that peculiar form of molecular motion which the one has lost in becoming specialized, the other has gained in becoming specialized. ”

“ Thus while molecular movement is a fundamental condition of Vitality, and is incessant throughout organized substance, the massive movements of the organism, and the movements of particular parts, are the directed quantities of this molecular agitation. They are due to stimulation. We distinguish this from mechanical impulsion. It is a vital process involving molecular change; it is not simply the communication of motion from without, but the excitation of motion within. It is not like the blow which merely displaces an object, but like the blow which disturbs its molecular equilibrium. ”

“ It was proved that no destruction took place, but that an exact equivalent of the energy of the lost molar motion appears as that of the molecular motion, or motion of the smallest particles of a body, which constitutes heat. ”

“ Any such molecular motion, moreover, may come from the arrested visible motion of a mass, and may in turn be liberated so as to resume the form of visible motion, as when an electric current is transformed into the onward movement of the trolley car. The change in our conception of Nature that has been wrought by this wonderful discovery is more profound than all changes that went before. ”

“ It is noteworthy, the we are led exactly to the above presupposed changes of dimensions, when we first (without consideration of the molecular motion) assume, that in a rigid body which remains at its own, the forces, attractions or repulsions which act on an arbitrary molecule, are mutually in equilibrium, and second — for which, however, there is no reason — when we apply to these molecular forces the law which we have derived in § 23 for the electrostatic actions. ”

“ Studies in molecular physics have led to this conclusion, that in a cubic centimetre of air the molecules which compose it only occupy a third of a cubic millimetre, that is to say, the 3/1,000 part of the total volume. It is like a cathedral in which children’s balloons might float, the remaining space being empty.
All these molecules, all these systems of atoms, are in perpetual motion like the worlds in space, and the structure of bodies is organised by invisible force. ”

“ When decomposition breaks up these highly complex atoms, and their constituents assume a gaseous form, there is both an increase of molecular motion implied by the diffusion, and a further increase implied by the resolving of such motions as the aggregate atoms possessed, into motions of their constituent atoms. So that in organic dissolution we have, first, an end put to that transformation of the motion of units into the motion of aggregates, which constitutes Evolution, dynamically considered ”

“ So that motion is essential to matter, is equally indestructible, and is directly proportional to its mass. He held that light, heat, sound, and the excitations of smell and taste, are all the results of molecular motion or vibration, as are also the agencies of electricity, magnetism, and gravitation. ”

“ A molecular medium, moving under such conditions that a group of molecules once near together remain near each other during the whole motion, may be capable of transmitting vibrations without much dissipation of energy, but if the motion is such that the groups of molecules are not merely slightly altered in configuration but entirely broken up, so that their component molecules pass into new types of grouping, then in the passage from one type of grouping to another the energy of regular vibrations will be frittered away into that of the irregular agitation which we call heat. ”

“ Our knowledge thus gained of the molecular and atomic structure of matter has been alone sufficient to remodel our conceptions of the universe from beginning to end. The case of molecular physics is equally striking. The theory of the conservation of energy, and the discovery that light, heat, electricity, and magnetism are differently conditioned modes of undulatory motion transformable each into the other, are not yet fifty years old. ”

“ Moreover, while we are thus enabled to conceive how light may work these molecular changes, we also gain an insight into the method by which the insensible motions propagated to us from the Sun, are treasured up in such ways as afterwards to generate sensible motions. By the accumulation of infinitesimal impacts, atoms of ponderable matter are made to oscillate. The quantity of motion which each of them eventually acquires, effects its transfer to a position of unstable equilibrium, from which it can afterwards be readily dislodged. ”

“ Evidently the greater the complexity of the molecular motions the less governable they are by any direct external force or influence we can bring to bear. This is because we are unable to act directly on the individual molecules and sway them to our special technical purpose. ”

“ A number of molecules moving in obedience to dynamical laws will pass through a series of configurations which can be, theoretically determined as soon as the structure of each molecule and the initial position and velocity of every part of it are known. The determination of the series of configurations developing out of given initial conditions is not, however, the problem of the kinetic theory: the object of this theory is to explain the general properties of all gases in terms only of their molecular structure. ”

“ These molecules, whether the string vibrates or not, have already their own activity and their own mutual action; only their actions balance each other as long as the mass of air is at rest. But when the string begins to vibrate, the equilibrium being broken near it, those molecules of air which first cease to be in equilibrium begin to act on the following molecules with a different intensity, according to the change of the molecular distance. Thus the movement by which the distance is altered is not the cause, but the condition, of the phenomenon. ”

“ We do not know that the particles of a molecule move within the sphere of the molecule by a system of rotations and revolutions, though such a system can be conjectured; but whatever the system may be, it must accomplish the same results by confining a certain portion of the speeds of the particles within the theater of the molecule by a system of deflections, and, whatever may be the motion of the molecule itself in relation to other molecules, the speed of the particle must be partly taken up within the molecule, and it must then be divided between internal motion and external motion. ”

“ In a word, then, every molecule of matter is at once a centre for the distribution of motion (sending out impulses which affect, sooner or later, every other atom of matter in the universe) , and, from the other point of view, also a centre for the reception of motion from every direction and from every other particle of matter in the universe. Whether any given molecule will on the whole gain motion or lose it depends clearly on the simple mechanical principles of give and take. ”

“ They move about among each other, and within each molecule the atoms are in motion. Each atom, again, has its own internal movement. But, if the world were made up of atoms and molecules alone, we should never know of their existence; and, to explain the phenomena of the universe, we must recognize the presence of a continuous universal medium penetrating all space and all bodies. This medium, which we call the luminiferous ether, or simply the ether, serves to keep up the connection between atoms or molecules. ”

“ The movements of the gaseous molecules are, however, so wonderful that it is hardly surprising that those who are invited to believe these things should demand satisfactory evidence as to the existence of phenomena, which from the nature of the case seem to lie out of the reach of direct inspection by the senses. The methods by which our knowledge of the constitution of matter has been obtained, is by reasoning from the phenomena which our senses reveal to the more refined and supersensible conceptions of molecular physics. ”

“ After an interval, when the light is again allowed to act, it has not only to overcome the molecular inertia, but may have in certain cases to reverse the negative swing. In the case of continuous radiation, on the other hand, the molecular action proceeds without hindrance. ”

“ From organic matter, as from all other matter, incident forces call forth that re-action which we know as heat. More or less of molecular vibration necessarily results when, to the forces at work among the molecules of any aggregate, other forces are added. Experiment abundantly demonstrates this in the case of inorganic masses; and it must equally hold in the case of organic masses. In both cases the force which, more markedly than any other, produces this thermal re-action, is that which ends in the union of different substances. ”

“ It should be noted, too, of these bodies, that though they exhibit in the lowest degree that kind of molecular mobility which implies facile vibration of the molecules as wholes, they exhibit in high degrees that kind of molecular mobility resulting in isomerism, which implies permanent changes in the positions of adjacent atoms with respect to each other. ”

“ If each pole or electron is connected with a molecule possessing extraneous mass, and it may be having an extraneous field of gravitational and other force of its own, and thereby interacting with other molecules, we shall want to know the forces exerted on that molecule by the surrounding æther, in order to form its own equations of motion, which must be combined with those of the æther-field around it in order to constitute a complete system. ”