30. With all due deference, I am of opinion that this distinguished philosopher has not been consistent in assuming that, agreeably to the Newtonian idea of ponderable atoms, the space in potassium not replete with metal must be vacant; since, according to facts established by his researches, or resulting therefrom, an enormous quantity both of the causes of heat and of electricity exists in metals. Moreover, agreeably to his recent speculations, those causes must consist of material, independent, imponderable matter, occupying the whole of the space in which their efficacy is perceptible. To the evolution of the imponderable matter thus associated, the incandescence of a globule of potassium on contact with water, may be ascribed, since it is the consequence of the displacement of such matter by the elements of water, which, in replacing it, converts the metal into the hydrated oxide called caustic potash.

31. The existence both of the causes of electricity and heat in metals is likewise confirmed by the fact that the inductive influence of a magnet is sufficient to cause all the phenomena of heat, electrolysis, and magnetism, as exemplified by the magneto-electric machine. The existence of the cause of heat in metals is also evident from the ignition of an iron rod when hammered, or the deflagration of wire by the discharge of a Leyden battery.

32. The superiority of metals as electrical conductors may be the consequence of the pre-eminent abundance of imponderable matter entering into their composition, as above alluded to in the case of potassium.

33. Graham, in his Elements, treating of electricity, alleges that the “great discoveries of Farraday have completely altered the aspect of this department of science, and suggests that all electrical phenomena whatever involve the presence of matter.” Unless the distinguished author from whom this quotation is made intended to restrict the meaning of the word matter to ponderable matter, there was no novelty in the idea that electrical phenomena involve the presence of matter, since the hypotheses of Franklin and Dufay assume the existence of one or more imponderable material fluids. But, on the other hand, if the meaning of the word matter is only to comprise that which is ponderable, the allegation is inconsistent with the authority cited. According to the researches of Farraday, there is an enormous electrical power in metals, and, according to his speculations, such powers must be considered as imponderable material principles, pervading the space within which they prevail, independently of any ponderable atom acting as a basis for material properties; the existence of such atoms being represented as questionable.

Electrical Phenomena attributed to Stationary, or Undulatory, Polarization.

34. It having been shown that in electrical discharges there cannot reasonably be any transfer of matter, so as to justify the idea of their being effected either by one current or by two currents, the only alternative seems to be that the phenomena are due to a progressive affection of the conducting medium, analogous in its mode of propagation to waves, as in the case of liquids, or the aërial or ethereal undulations to which sound and light are ascribed. (1, 2, 3, &c.)

35. The idea intended to be conveyed by the word wave, as applied in common to the undulatory affections above mentioned, and that which is conceived to be the cause of the phenomena usually ascribed to one or more electrical currents, requires only that there should be a state of matter, which, while it may be utterly different from either of those which constitute the waves of water, light, or sound, may, nevertheless, like either, pass successively from one portion of a mass to another.

36. The affection thus designated may be reasonably distinguished from other waves, as a wave of polarization, since the wire acts, so long as subjected to the reiterated discharges of a voltaic series, as if it were converted into innumerable small magnets, situated like tangents to radii proceeding from its axis.

37. But if a polarizable medium be requisite to electrical discharges, since they pass through a space when devoid of ponderable matter, there must be some imponderable medium through which they can be effected. Hence we have reason to infer that there is an imponderable existing throughout all space, as well as within conductors, which is more or less the medium of the opposite waves essential to electric discharges. Quoting his own language, Davy’s experiments led him to consider “that space, (meaning void space,) where there is not an appreciable quantity of this matter, (meaning ponderable matter,) is capable of exhibiting electrical phenomena:” also that such phenomena “are produced by a highly subtile fluid or fluids.” Moreover, that “it may be assumed, as in the hypothesis of Hooke, Euler, and Huyghens, that an ethereal matter susceptible of electrical affections fills all space.”

38. Agreeably to the suggestions above made, all ponderable matter which is liable to be electrified internally by electrical discharges, may be considered as consisting of atoms composed of imponderable ethereo-electric particles in a state of combination with ponderable particles, analogous to that which has been supposed to exist between such particles and caloric when causing expansion, liquidity, or the aëriform state. Atoms, so constituted of ethereal and ponderable particles, may be designated as ethereo-ponderable atoms.[65]