Chapter XXII: Part 22

1826. According to the doctrine which chemists have heretofore suggested for the existence of matter in the elastic or gaseous state, each aerial or gaseous atom was conceived to be enveloped in an atmosphere of fluid called caloric, resembling the ether in the self-repellent power of its constituent particles. This atmosphere has been assumed to impart to atoms which it envelopes its own inherent power of reciprocal repulsion, like that which those of the ether have. But Dalton showed that there was no repulsion between gaseous atoms when _heterogeneous_. Two or more such gases, hydrogen and nitrogen, for instance, being comprised in the same cavity, there would be no repulsion between the atoms of hydrogen and those of nitrogen, but only between those of the same gas. This has been held to be equally true, however many gases might be mingled, or whatever vapours might be superadded.

1827. The idea is thus refuted, which ascribes the repulsive power to the same elastic fluid, since in that case the diversity of the gaseous atoms could not so affect the repulsive influence as to nullify it between heterogeneous atoms, while sustaining this repulsion, where the atoms should be alike.

1828. Moreover, as the rays of light have been found to be mere undulations in the ether; the rays of heat, being perfectly analogous in their attributes, must also be due to ethereal undulations. But vaporization may be affected by radiant heat, and gases owe their aeriform state to the same cause as vapor or steam; yet transient undulations evidently cannot form a permanent combination, so as to confer the durable elasticity of a permanent gas.

1829. It appears, then, that neither the doctrine of caloric, nor the undulatory doctrine, as it is received, will explain the creation of permanent gas. Under these circumstances a modification of the existing opinions is called for. It has, for some years, occurred to me, that the Newtonian doctrine of radiation might be associated with that of undulation.

1830. The fact that radiant heat could be collected by a mirror so as to raise the temperature of bodies placed in the focus, and that this process could take place in vacuo, as ascertained by Sir Humphrey Davy, had been adduced as unquestionable evidence of the materiality of caloric, the supposed fluid cause of heat. But as the cold proceeding from a snowball or any cold body could be collected by the same process, it was urged by some chemists that the evidence of the materiality of the cause of cold must also be admitted. Prevost met this argument by suggesting that no body in nature is absolutely cold. Every body, however refrigerated, is not so cold as to be incapable of greater refrigeration. Hence all bodies being absolutely above the zero of nature, are throwing off rays to each other, and where there is equality of temperature, they do not cause any change in their relative temperatures. The rays thrown off by A are compensated by those which it receives from B, and _vice versa_. But if A throws off to B more than B reciprocates, the temperature of A must fall until an equilibrium is attained. Thus, A being the mirror and B the snowball, the mirror is refrigerated, and causes a greater radiation from any body situated about its focus. This explanation was generally received, but to me, the following rationale, which I advanced, appeared preferable:

1831. I assumed caloric to exist throughout the sublunary creation, as the luminiferous ether is assumed to be diffused throughout all space by the undulationists; the diffusion arising from the reciprocal repulsion of its particles being similar to that which had been supposed to cause the diffusion of caloric. There is the greatest analogy between this diffusion and that which is known to exist in the case of gases. The process is the same, whether the gas be dense like chlorine, or thirty-six times as rare, as in the instance of hydrogen, and in the luminiferous ether resembles the process by which hydrogen is rarified, or might be rendered more rare, were the pressure of the atmosphere removed.

1832. It is known that in any gas or gaseous mixture like that which we breathe, if a deficit of pressure be caused in any spot, the gaseous particles will quickly move toward it, in order to restore the equilibrium of pressure, and that if, on the other hand, any augmentation of pressure be produced at any spot, the gas will move outward to restore the equilibrium.

1833. The particles being symmetrically arranged in lines, a row of particles may be conceived to lie between every two remote points. If we suppose any number of points in the focal body, and a corresponding number in the surface of the mirror, it may be conceived that the intervening ethereal or calorific particles will move in rows one way or the other, as the pressure in the focal space may become greater or less. Thus an effect is brought about, equivalent to that which the Newtonian idea of radiation involves; lines of particles proceed from the hotter points to the colder ones.

1834. The arrangement of the particles of caloric, which was originally, in my view, confined to the sublunary creation, appears of necessity to belong to the luminiferous ether, required by the theory ascribing light to undulations, though the last-mentioned medium must be endowed with ubiquity as above stated, so as to abound in every part of space through which light reaches the eye.

1835. The undulatory hypothesis supposes that a wave-like motion being imparted to a row of particles, by a luminous point in the surface of the luminous body, is transmitted, like the sound producing waves in the air, to the other end of the row.

1836. This undulatory progression has been roughly illustrated by the transitory serpentine movements which may be made in a cord, stretched like a clothes-line between the tops of posts.

1837. In order to make this illustration elucidate the conception which I advance, we have only to suppose that the cord, instead of being attached to the post, should be drawn rapidly over pulleys, and, while thus actuated, be subjected to a cause of undulatory vibration. It may be conceived that, by this process, the ethereal particles, while performing all which the undulatory theory requires, might at the same time perform all required by that of emission and material calorific radiation. Directed upon a vaporizable liquid, the undulations might perform the part of sensible heat; the ethereal particles, successively combining, might furnish the latent heat requisite to the constitution of vapour.

1838. Agreeably to Newton, the seven colours of the spectrum are due to as many different kinds of radiant particles of various refrangibility, or susceptibility of being bent from the rectilinear path when passed through the same refracting medium.[40]

1839. According to the undulatory theory, the colours are caused by diversities in the undulations producing them. Retaining this feature, the last-mentioned hypothesis, as modified by myself, appears to be competent to explain the phenomena of light as well as those of vaporization, produced by calorific radiation, since not only is any vaporizing liquid subjected to the transient effect of the undulations, but also may combine with the ethereal particles as they come into contact with it.

1840. Thus modified, the rationale of the rainbow, or prismatic spectrum, would not be that the colours indicate as many varieties of original radiant particles, but that they are to be explained agreeably to the undulatory hypothesis, which ascribes them to as many varieties in the undulations, just as the notes in music are ascribed to diversities of vibration.

1841. The ether, under this view, performs the part heretofore assigned to latent heat, by combining with solids so as to render them susceptible of expansion, and of electrical conduction by being liable to the polarization which constitutes electricity.

1842. Sensible heat, according to this aspect, is due to the vibrations of the ethereal fluid, which is sustained by the sun, by ignition in the interior of the earth, and by chemical reaction, including combustion and respiration.

1843. The correctness of the inference, that conductors owe their conductive power to ethereal matter entering into their composition, has been insisted upon in my strictures on Farraday’s speculation in some of the preceding pages. The facts admitted by this distinguished investigator of nature’s laws, gave to me a basis on which to rest an argument in favour of the existence of an imponderable cause of heat and electricity in metals, which seems to me unanswerable.

1844. Agreeably to the hypothesis respecting which the preceding preparatory suggestions have been made, gasification is not due to a repulsive atmosphere of ethereal matter, severally appropriated to each ponderable constituent atom, but to an attraction for every such atom exercised by the ethereal fluid, such as water exercises toward sugar, quick-lime, salt, or any soluble substance. The ether attracts the particles of certain solids, and is of course reacted upon by them. The particles thus attracted naturally distribute themselves throughout it, at symmetrical distances. Hence the law of Pettit and Dulong is verified, which, at least, holds good with all gasifiable atoms, that their capacity is inversely as their atomic weight.

1845. The atomic weights of hydrogen, nitrogen, and chlorine being severally 1, 14, 36, when associated with equal volumes of the _imponderable_ ether, they will have still the same weight. Equal volumes will weigh the same as the atoms with which they are associated; and the capacity for heat, being directly as the volumes, will be inversely as the weights, the calculation being the same, whether ether or caloric be the imponderable principle to which they owe their gasification. By concurring with those chemists, who estimate the atoms of oxygen at 16, instead of 8, this gas will come into the same calculation.

1846. When heterogeneous gases are confined within the same cavity, that they should not react with each other is no more wonderful, than that the same mass of water may at the same time hold different substances in solution, which may add to its hydrostatic pressure though they have no reciprocal reaction.

1847. Sensible heat appears to be due to vibrations in the ether, kept up by the solar rays or central ignition within this globe. By the heat thus acquired the self-repellent power of the ether is augmented. When by refrigeration this source of repulsion is diminished beyond a certain limit, the atoms of certain vaporizable particles, such as those of steam and other condensible vapours, are approximated sufficiently to attract each other, and consequently coalesce and are condensed.

1848. It follows that light is due to _undulation_, sensible heat to _vibration_, and electricity to the _polarization_ caused in the ethereal medium, while either in a free, or in a combined state. Thus this luminiferous ether performs the part heretofore attributed to latent heat or caloric in one state; in another state, that of sensible heat.

_Suggestions of Massotti, respecting the Nature of Matter._

1849. Massotti has suggested that all bodies consist of two kinds of ultimate particles; that any two or more particles of one kind are repulsive of each other, while any two or more of different kinds are reciprocally attractive. Hence atoms are formed, consisting of one atom of one kind and one of the other kind. Of course, were the opposite forces exercised by the heterogeneous and homogeneous equal, the resulting atoms would be neither attractive nor repulsive; but assuming the attractive power to have the ascendency, the hypothesis would account for the property of gravitation.

1850. Let the suggestions of Massotti be modified, so far as that the extremities of each particle, whether of one or the other kind, are to be considered as endowed with opposite polarities, like those of the magnetic needle, as already suggested in the case of matter in general. Then in one relative position of the extremities they may be reciprocally repulsive, in the other reciprocally attractive; likewise one of the kinds of matter, like the light-producing ether of the undulationists, may pervade the universe, and be condensed in a peculiarly great quantity within perfect conductors: all this being premised, it may be conceived how the waves of opposite polarization, which proceed from oppositely electrified, or in other words, oppositely polarized bodies, cause the matter through which they pass to be decomposed or explosively rent.

1851. As elsewhere stated, in large bodies of water, waves are the effect of transference of motion successively from one part of the mass to the other; the rolling of the wave causing nothing to pass but the motion, and of course, the momentum is invariably consequent to motion. The waves by which sound is transmitted, are analogous; nothing being transferred excepting a vibration of the air, capable of affecting the tympanum of the ear with the impression requisite to create in the sensorium the idea of sound.

1852. Any affection of matter, capable of existing in successive parts of a material body, so that while the body is stationary, the affection passes from one part of the mass to others, may be considered as a wave of that affection, as reasonably as the affection called momentum is considered as producing a wave in water, when passing through it, as above described. It is in this way that I consider that the term wave of polarization may be applied to an affection of matter consisting of an abnormal position of the poles of the constituent particles, successively induced in rows of atoms, so as to proceed from one part of the series to the other.

1853. And as two sets of waves, of which the hollows of one should correspond with the elevations of the others, would, by being associated, produce an even surface and equalization of the momentum in the aqueous liquid, so, in opposite polarities, there might be reciprocal neutralization by the coming together of the polarities.

_On Electro-polarity as the Cause of Electrical Phenomena._

1854. Agreeably to the view which I take of the present state of our electrical knowledge, the phenomena designated under the name of electricity are due entirely to a process which I designate as polarization, and the consequences thereof. Those attractions and repulsions which have been found to exist between particles of matter, instead of being an endowment of the whole mass of each particle, seem confined, as already suggested, to particular terminations or spots, as we see this property on a larger scale in the loadstone or natural magnet. In the body long known under this appellation, the attractive power which it exercises is displayed usually at two distinct portions of its superficies, which are called poles. When a piece of steel wire is duly rubbed by either of these poles, it acquires a similar attractive polarity, which always appears at the extremities. When formed into an appropriate shape and freely suspended, such a wire magnet constitutes the compass needle, having the wonderful and all-important faculty of arranging itself within a meridian plane, so as to be always nearly north and south; the same pole invariably pointing in the same direction. The poles are named from the quarter to which they point, one being called the north pole of the needle, the other the south pole. This involves that the north pole of the earth itself has nominally south polarity; the south pole, north polarity.

1855. When two suspended compass needles are sufficiently approximated, it will be seen that between the poles which point in the same direction, there is repulsion; between those which point in different directions, attraction. When the dissimilar poles are brought into contact, they adhere; and if left cohering, will continue attached for any length of time; and while in that state of coherence, the magnetic power of the poles thus touching, being neutralized, disappears.[41]

1856. If two needles be laid parallel, an interval between them, the extremities being made to communicate by applying two wires of suitable dimensions, also parallel to each other, the magnetic power will be neutralized.

1857. It is inferred that analogous phenomena take place in the particles of masses or surfaces which are endowed with chemical affinity or even cohesive attraction.

1858. It is to the existence of the power by which these effects are caused, at opposite terminations, that bodies, in congealing or freezing from the state of liquidity, shoot into prismatic, oblong, regular forms, called crystals. This is illustrated in the formation of ice, which is seen to shoot into such prismatic crystals.

1859. When a pane of glass is so situated as to have the focus of a solar microscope thrown upon any spot, so that the glass thus affected may be between the eye of an observer and the microscope, any small crystals formed are greatly magnified. Hence if the focal space be moistened with a solution of certain salts, the solvent evaporating, crystallization ensues, and is seen to form appropriate figures for each salt employed. It is owing to this property that when certain solutions of various substances are evaporated, the soluble solid, as it is deposited from the solvent, arranges itself longitudinally; one atom attaching itself to the pole of another, until it creeps over the sides of the vessel in great quantity. The appearance of arborescence in certain minerals is thus accounted for. When an amalgam of mercury with silver is hung by a platina wire within a bottle of a solution of silver in nitric acid, there is formed a beautiful branching of silver filaments. These are longer, though more slowly formed, as the solution is more dilute. In very dilute solutions I have seen prisms of silver of more than an inch in length, so delicate, that but for the brilliancy of the surface they could not have been detected by the eye.

1860. Farraday distinguished two kinds of polarity—ferro-magnetic and dia-magnetic. That above described as taking place between steel magnets is designated as ferro-magnetic. Dia-magnetic particles under magnetic influence take position at right angles to that which would ensue from ferro-magnetism.

1861. This explanation being premised to enable the student to comprehend what is meant by polarity, I will proceed to explain electric phenomena, according to the theory which I hold.

1862. It is expected that the preceding discussions have prepared the reader to conceive that the atoms of all ponderable matter are endowed with two analogous but opposite polar powers, which we term polarity. That in any two atoms the dissimilar polar powers tend to make them unite, the similar powers having the opposite tendency. That in any inert mass the opposite powers or polarities are in contact, and thus reciprocally neutralized.

1863. It will be also understood that the ethereal fluid which pervades the universe as the means of illumination is assumed to consist in like manner of atoms or particles which are endowed with polarity, so that when the opposite poles are in proximity, there is neutralization: repulsion, and disturbance, when similar poles are approximated. This being premised, the allegation may be intelligible, that when bodies are electrified, the poles of the component atoms or particles are conceived to be deranged from their natural position of reciprocal neutralization, so that they react with exterior bodies, disturbing the poles of their constituent particles, and thus electrifying them by induction.

1864. This abnormal state of disturbance, is conceived to be produced on glass or resin, or any electric, when duly subjected to friction.

1865. Thus when in an electric machine a vitreous surface is rubbed by a leather cushion, the particles both of the leather and glass surfaces are deranged from their natural state of reciprocal neutralization, and present their poles in an active state, and the glass surface, moving through the ethereal medium, (812) polarizes it as it passes, the ether resuming its normal state till the ethereal atmosphere over the conductor is reached. To that it imparts durable polarity; the metallic superficies of the conductor taking the opposite state, so that the charge is retained until the glass goes to and returns from the cushion, with a farther supply of polarity.

1866. The charges of polarization received by the plates at each succeeding revolution of the plate or cylinder, is divided with the ethereal atmosphere over the conductor, and this process is reiterated till the frictional power has accomplished its maximum effect. Then the conductor is said to be charged positively, according to the theory of one fluid, and vitreously, according to that of Dufay, or the theory of two fluids. Meanwhile, if the cushion communicates duly with an insulated conductor, a process perfectly analogous to that just described has been charging that conductor, _pari passu_, with the one first mentioned. By these means we have two excited or charged conductors.

1867. If, before charging these conquerors, two scalps of hair be severally situated on them, it will be perceived that, as the charging proceeds, the hairs on each of the scalps rise, and endeavour to keep away from each other. But, meanwhile, the whole of the hair on either is attracted by that on the other conductor. Moreover, on touching both conductors with any metallic rod, simultaneously, the whole of the excitement disappears, and the hairs assume their normal position.

1868. In producing this discharge, iron is not more effective than any other metal. It is, in fact, known to be less competent for this species of conduction, than copper, silver, or gold.

1869. When the conductors are excited they have a powerful effect upon gold leaves, suspended as in the electrometer.

1870. The state of the conductors, when excited, as described here, is said to be _static_. Such a state of excitement is distinguished as a _statical_ charge of electricity.

1871. In the next place, if we procure a horse-shoe magnet, lay it on a table, cover it with a sheet of paper, and then sift over it iron filings, we shall see the shape of the magnet delineated upon the paper, by the filings arranging themselves above its corners in preference. But as the sifting proceeds, the filings will be seen to extend themselves in filaments, so as very much to resemble the electrified hair above described. A tuft of the ferruginous filaments will be formed upon each pole of the magnet, each filament avoiding its neighbours, as far as possible. But while each filament, in either tuft, avoids every other in its appropriate tuft, the whole of the filaments in one, are attracted by those in the other. Thus, the charges of polarity which cause each similarly polarized filament to avoid those in the same state, induce those polarized by one of the poles of the magnet, to attract such as are polarized by the other pole of the magnet.

1872. Here is, so far, a great analogy between the phenomena of the polarization of filings and the polarization of the hair, above described. But then there is this difference: excepting iron, cobalt, and nickel, there is no metal which can, by contact with the poles of a magnet, neutralize the polarity by which the iron filings are affected; and even these metals produce this result by a process, the inverse of that by which charges of statical electricity are neutralized. In fact, the magnetic metal, far from acting as a discharger, acts as a keeper; and a piece of iron, of a suitable shape, applied to the terminations of a horse-shoe magnet, prevents the gradual diminution of the magnetism, which otherwise ensues. Hence the name keeper is applied to it, as well as armature, derived from the French.

1873. It will be perceived that, in a steel magnet, the charges are sustained at the terminations of a conductor, which, as estimated by Cavendish, conducts electricity with a velocity two hundred thousand times as great as water.

1874. The charge of the conductor of the machine is superficial, a gilt globe of glass holding as good a charge as a solid globe of metal; and, moreover, in this superficial charge, the ether and the air participate, undergoing a polar affection, analogous to that of the filings exposed to the influence of the magnet.

1875. On the other hand, in the use of the steel magnet, the charge is internal, and, other things being equal, increases with the quantity of iron charged; neither the air nor the ether participate in this magnetic charge. There is no mode in which the charges of the poles of a magnet can be made to pass from one to the other, through any interposed conducting mass.

1876. The retention of the charge seems to be dependent upon a state of the particles in which they are capable of being deranged from their normal position with a certain degree of extraneous influence, and can only resume their natural relative position by a contrary application of a similar agent. Although steel differs from iron only in containing, as an ingredient, one-fiftieth of carbon, this gives it the highly valuable property of hardening, when suddenly refrigerated; a result which may be accounted for by supposing that, in consequence of the sudden exposure to a powerful conducting medium, there is a sort of a jerk by which the particles loose from their midst an undue portion of their ethereal constituents, and cannot recover their normal arrangement after the refrigeration. When this effect is reached to a maximum, the steel is so brittle as sometimes to fly into two or more pieces when left to itself. When soft iron is subjected to the magnetizing process, it exchanges one polarity for the other with such speed, that, in some electro-magnetic instruments, this reversal is effected more than one hundred times in a second; but precisely in proportion as the magnetism is readily received, it is more readily lost. On the other side, when hardened to a maximum, steel can scarcely be magnetized at all. Thus, to have a permanent magnet, we must employ the metal in a state of induration between the extremes. These facts tend to corroborate the inference that magnetism is dependent on the relative position of the ferruginous particles. It is presumed that the ferruginous particles of which the filings consist indicate, by their direction, as seen externally, the direction in which the constituent particles of the magnet are situated beneath the metallic surface.[42]

1877. If to a wire, connecting the poles of a galvanic battery, iron filings are applied, each ferruginous particle becomes a little magnet, and displays exactly the same disposition to unite in filaments as has been represented to take place when they are exposed upon a sheet of paper, to the influence of a magnet supporting it. But while this affection is thus identical with that induced by the steel magnet, it differs therefrom, in its being as transient as the galvanic discharges to which it owes its existence. These, at the lowest estimate, are sufficiently rapid to go round the globe in two seconds; whence it may be conceived that the time taken to percur a few inches of wire must be almost infinitely brief. Hence, although the filings continue in a state of magnetization so long as the action of the battery is sustained, and the wire kept in due contact with the poles of the battery, it is only by a rapid reiteration of discharges, that this result is effected.

1878. As the relative position of the particles composing the steel magnet has been inferred to be indicated by that of the movable filings which they influence, we may suppose the position of the particles composing the wire, to be indicated by that which the filings take by which it is encircled. These are situated always as if forming tangents to the circumference of the wire, and hence it may be perceived that the metallic particles, forming the wire, have been shifted from their normal position, parallel to the axis, so as to take that tangential direction which the magnetization evinces.

1879. On one end of the wire being in communication with one pole of a voltaic series, on touching the other pole of the series with the other end of the wire, filaments of the particles previously situated parallel to the axis, are jerked out of the normal position with an inconceivable quickness, the discharge, however, not affecting successive parts of the length absolutely at once, but successively; so that there is a time required for the process, however inconceivably minute it may appear to us. The effect upon the filaments of filings, at the different ends of the wire, are perfectly simultaneous, and the effect analogous, but different in this respect, that the positive poles are presented externally at one end, the negative at the other, so that, when the polarizing affections meet at an intermediate point within the wire, neutrality ensues.

1880. Thus it will be perceived that no current passes through the wire, any more than the water which is seen to form a wave, on one side of a lake, passes with the wave which is seen apparently to proceed to the other side. Notoriously, in this case, nothing passes but the momentum, which is successively imparted to successive portions of the intervening water; so, in the galvanic discharge, successive portions of the intervening wire are affected by the original disturbing jerks, of which the power passes from each portion to that next beyond it, just as the momentum in the case of the aqueous wave.

1881. Upon these considerations I hold myself as warranted in calling the affections of the wire, as described, _waves_ of polarization, not that the affection of the wire has the smallest similitude to that with which water produces waves, but that, in both cases, there is a successive communication of a property. It is well known that there is this analogy in the two cases; in either, opposite waves, on due meeting, produce reciprocal neutrality.

1882. The neutralization of the electro-polarity induced upon the charged conductors (1867) by touching both at the same time by a conducting rod, is effected in some degree analogously to the process in the voltaic discharge; since waves of opposite polarization are produced at each extremity, and, rushing toward an intermediate point, are neutralized by meeting. But the polarization in the case of the conductors, as has been stated, (1874,) is superficial, and extends not only to the surfaces of the conductors, but likewise to the surrounding ether and air, and does not affect the ponderable atoms of the wire unless the charge be too great to pass in this superficial manner. In that case, being condensed upon the wire to a state of great intensity, it causes a polarization of the atoms composing it, similar to that of the voltaic discharge, though less durable.

1883. From the preceding exposition it follows that the conduction and insulation of that species of electricity which is excited by an electrical machine or other frictional processes, exists upon the superficies of insulated masses, or that of the circumambient particles of the air or ether. This frictional electricity likewise passes preferably over the surfaces of conductors, so that the moistened surface of glass, or other non-conductors, conveys it with enormous facility. It is notorious, that when the air is moist, electrical machines are paralyzed. But this cannot be in consequence of the moist air acting as a conductor. Agreeably to some experiments which I made, a fog from hot water does not act as a conductor. Evidently, were a fog or a cloud a conductor, the air and moisture forming a thunder cloud could not be electrified, so as to give the discharges which constitute lightning.

1884. It is well known that a tube will carry more lightning than a rod, of which the sectional area should comprise the same quantity of metal. Yet, when the wire is too small to carry a charge outside, it is acted upon intestinally and may be explosively deflagrated. But while the existence of a film of moisture upon the glass legs of an electrical machine, may paralyze its power, to a powerful galvanic battery moisture is well known to be essential.

1885. If the poles of a powerful voltaic series, while highly charged, were severally to have a conducting communication with the conductors of an electrical machine, it would discharge them so rapidly, that the most active working would not enable them to give a spark; yet at the poles of the same series there might be charges accumulated which would, in effecting chemical decomposition, heating, deflagrating wire, or inducing magnetism, be immensely superior to that created by a machine.

1886. Farraday’s reasoning and observations, founded on the idea that the only difference between galvanic and frictional electricity was that between quantity and intensity, led him to take up the idea that a grain of water with an equivalent of zinc would evolve as much electricity as sixteen millions of square feet of coated glass, charged by a powerful machine of fifty inches in diameter. I am surprised that Farraday did not consider his premises erroneous, when he found them involving such startling conclusions.

1887. The source of this startling inference was, I think, as follows: Farraday entertained the opinion, that the only difference between voltaic and frictional electricity was that of quantity and intensity. He went so far as to intimate that this opinion would be entertained the more confidently as the electrician forming his decision should be better acquainted with the subject. I advanced what appeared to me unanswerable objections to this conclusion, but such as were not deemed by him worthy of reply. Unduly confident in his postulate, Farraday first ascertained the greatest effect which could be produced by a certain number of turns of a powerful machine, with a fifty inch plate, in causing a deviation of the galvanometric needle, and then, comparing the quantity of zinc and water required to produce the same effect through galvanic action, by a rule-of-three statement the result above mentioned was obtained. In my view the error arose from overlooking the fact that in the one case the whole discharge was exercised in polarizing the ponderable matter, while in the other only a portion of the discharge was thus employed, being only a secondary effect of the polarization of the circumambient medium. Only that portion of the charge which was forced into an association with the ponderable matter, had any effect on the galvanometric needle.

1888. According to Gaziot’s experiments, a Grove’s battery of 320 pairs would not give a spark before contact at any distance, although frictional machines, proportionally powerful, have given sparks at twenty inches.

1889. Thus the laws of conduction and insulation, as respects the two kinds of electricity in question, are different; the waves of polarization are in the case of the galvanic circuit confined to absolute contact with conducting ponderable matter. It cannot pass through the electrical medium or the air by the disruptive process. When once a passage has been made for it, it may pass convectively, carrying with it the polarizable matter, as may be seen in the arch formed between the poles of a powerful voltaic series after contact.

1890. This arch cannot be formed between two metallic points, because none but those of a most fixed and infusible nature can support the heat produced. It is only between charcoal points that it can be created, because no other competent conductor is infusible at the temperature of its volatilization. It is in fact only by the process in question, that charcoal can be volatilized _per se_. It may be inferred that as those waves of electro-polarity which require the presence of ponderable as well as ethereal matter cannot pass over an interval without the assistance of ponderable matter such as is supplied by the coal. On contact with each other, the points completing the circuit are subjected to an intensity of the polarizing power which causes the carbon of the points, in the state of vapour, to become associated with the ethereal waves, and thus produces the flaming arch, which distinguishes the scene of reciprocal neutralization.

_Of Mind, as existing independently, and as distinguished from Matter._

1891. Three ideas must coexist in every rational being; nihility, mind, and matter. We can, of course, conceive of a perfectly void space, and likewise of a mathematical point, which designates a position not an entity. Yet, position cannot be determined without surrounding entities, between which this point exists, without having claim to any portion of those entities, whether there be only one actual material surface, or where several are cornered together. Of such points we have already treated, as forming at the immovable centre of a rotating mass, so that a centre is, of course, one state of the existence of such a point.

1892. After the considerations already presented, it will be seen that there is great difficulty in conceiving of the existence of an atom of matter endowed with polarity, and of course with two centres of two analogous, but opposite and irreconcilable forces. And we must consider that there are more than fifty such heterogeneous elementary atoms, all endowed with various degrees of affinity, so as that two may unite energetically to the exclusion of a third. This is designated as a case of decomposition, and may be exemplified by the process in which water is explosively decomposed by potassium, with which the oxygen of the water unites to the exclusion of hydrogen. When we see that from seven parts, by weight, of charcoal, and about nine parts of water, sugar ensues; that the sweetness with which this sugar is endowed, is the result of a difference between this substance and starch, in the proportion of the watery elements: starch consisting of less water than sugar, with the same amount of charcoal; when we learn that twelve parts, by weight, of charcoal, fourteen parts of nitrogen, and one of hydrogen, constitute the deadly prussic acid; and when, in fact, we discover that the atoms of matter which compose our flesh are capable of entering into as many active chemical combinations as the beads of a kaleidoscope can be productive of figures, then it will be manifest that the phenomena characterizing what we call matter, as well as the powers of that matter, are such as to prove our utter incapacity to comprehend the powers and properties of material atoms, and that we must not object to any wonder that nature may produce, because it is beyond our comprehension.[43]

1893. The belief in the powers displayed by matter does not then result from their being explicable, but from their being evident, just as the elaboration of the chick from the egg demonstrates the fact that the yolk and the white have been converted into a chicken without our being enabled to comprehend the process by which it has been effected. Such being the imperfection of our knowledge respecting the intricate nature of matter and its reactions, it seems to me inconsistent that there should have been such backwardness to believe in the independent existence of mind, of which the phenomena and properties are quite as evident as those of matter, the mode of existence and operation in either case being inscrutable.

1894. The great distinction between mind and matter is the presence of will on the one side, and the absence of it upon the other. _Vis inertiæ_ is the antipodes of will; and if gravitation have any association with will, it will be that of the Creator; but in the inert mass actuated, it serves only to add to the evidence of incapability of self-actuation.

1895. Passion and reason, the parents of will, are properties as manifest as those which, surrounding a centre, give to it that idea of a central force which indicates the presence of material atoms, though it does not constitute them, as I have urged.

1896. The existence of _vis inertiæ_, gravitation, and chemical affinity, is not more evident as properties of ponderable matter than reason and passion and consequent will are of mind; nor is will less evidently the offspring of reason and passion, than momentum is of _vis inertiæ_ and gravitation. The existence of these attributes of mind is as evident as is the existence of those of ponderable matter, and the incomprehensibility of their origin or mode of operation should no more be an obstacle to belief in the former case than in the latter.

1897. Nothing is more thoroughly fundamental and essential in the doctrine inculcated by revelation than the omnipotency of the will of God. According to Scripture, the whole heaven and earth, and all that is in them, sprung into existence in consequence of the fiat of the Deity, whose will, under the designation of “overruling providence,” is alleged to regulate every thing, even to the fall of a sparrow, or the advent of a pestilence. It follows that the suggestions which I have made respecting the powers of mind are perfectly orthodox, so far as the mind of the Creator is concerned; and as, according to orthodoxy, man is made after God’s own image, however humble and minute may be the being so made, his mind, so far as it exists, must be, within the sphere allotted to it, existing upon an analogous footing to that of its author. The idea of all things coming from the creative power of God as the first cause, involves the existence of the divine-will power, of the first cause; and consequently, beings endowed with an analogous will, must, so far as they have any available existence, be endowed with will-power, of which the potentiality may be more extensive in spirits than in mortals.

1898. It is because there is no other imaginable power which can be productive of the rationality of the universal creation, that forms the great argument for assuming the will of a reasoning Deity to be the cause of causes. Vain were it to appeal to any irrational force under the name of odylic, or any other, to explain the divine attributes on which this argument reposes. In like manner, the assailants of Spiritualism cannot find any nominal force, whether new or old, which can explain the rationality of the results which I have submitted to the public in this book, as coming from the minds of my spirit friends.

_Of Spirit independently, or as distinguished from Mind and Matter._

1899. It has been alleged above, that three ideas must exist in the conception of every rational being; nihility, mind, matter.

1900. Mind is distinct from matter in its usual acceptation; but it also differs from nihility. There are some attributes common to mind and matter; since they cannot be considered as nothing, they must both be something. Therefore, the word thing applies to either, and thing is sometimes received as synonymous with matter. But between these two kinds of things, mind and matter, we have an intermediate thing called spirit, which is sometimes confounded with mind. In its original sense, this word merely denoted a thin or refined matter, such as air, wind, breath. In chemistry, it has been applied to every thing obtained by distillation, as, for instance, spirit of wine, spirit of salt, spirit of nitre, of vitriol, spirit of turpentine.[44]

1901. Hence, by analogy, when the mind of a mortal, after death, was seen, or supposed to be seen, in a shadowy form called a ghost or shade, it was conceived to be the spirit or essence of the mortal body which it had inhabited. It was the body which the mind took or kept for its integuments after abandoning its perishable mundane _casket_, as the spirits are wont to call the carnal body.

1902. It is difficult for us mortals to conceive of mind without such a spiritual body. Yet, agreeably to information from my spirit friends, the substances of which the bodies, the country, and habitations of spirits are constituted, seem to have the attributes of materiality no less than the substances of which the bodies, the territory, and the habitations of mortals are constituted. Their spiritual substances perform for them the same offices as our material substances do for ours, yet it is expedient to distinguish them by different appellations, and those cited here have been sanctioned by custom at least as far as the time of St. Paul, or when these words in Genesis were first used: “The spirit of God moved on the surface of the water.”

1903. Hence, the words materialism and materialist have been made synonymous with unbelief or unbeliever in a future state of _spiritual_ existence.

1904. Spirit has also been confounded with mind or soul, or so associated that we speak of the spirit of a friend, when intending to convey the idea of soul or mind.

1905. The soul seems to be understood as the basis both of the passions and the reason, uniting both the power of thinking and reasoning with those of loving and hating, of benevolence and malevolence, so that even the soul of Jehovah has been represented in Scripture as being actuated by jealousy, wrath, and vindictiveness.

1906. According to information from the spirit world, spirit is viewed as the clothing of the soul, and is not constant in its characteristics; but, on the contrary, varies with the plane which it occupies, so that its density is inversely as the rank attained. It is on this account that the inferior spirits cannot rise above the level to which they rightfully belong.

1907. The impression is conveyed that there is a state to be attained in the spiritual heaven, wherein the tenuity of the integuments of the soul are still more refined.

1908. According to the speculation in which I indulged in a previous page, a centre cannot differ from the nihility involved by the conception of a mathematical point, without a circumambient something, to which the difference is due, and, however difficult to conceive in what way the attributes of a human soul are associated about the centre whence their influence proceeds, this difficulty, having been shown to exist no less in the case of ponderable atoms, would be an objection to the existence of matter as much as of mind.

_Of the Soul, as distinguished from Mind and Matter._

1909. The word mind is much used as synonymous with intellect or understanding, though it seems to me we consider it as more or less associated with the passions which actuate it. The word soul, on the other hand, involves the association of every thing which distinguishes a being capable of passion, and competent to reason, from a corpse. It is remarkable that, as spirits become more pure and intellectual, they should be alleged to become more refined in their spiritual integuments, thus removing further from the mundane state, and becoming less capable of giving those manifestations in which violent movements are witnessed.

_On the Odic, or Odylic, Force._

1910. There never was perhaps a more eloquent exhibition of that which has been designated as _ratiocinatio verbosa_, than in the appeals made to the odic force as the means of explaining spiritual manifestations. It may be inferred, from the speculation into which I entered, when treating of mediumship, (806,) that there is a spiritual light and spiritual electricity, which performs for spirits in the spiritual world what our electricity and light does for us in this world. It was pointed out that the term magnetism had been applied to mesmeric phenomena rather in consequence of an analogy between them and those of electro-magnetism, than from any identity. To this spiritual electricity, mortals, in their spiritual organism, which coexists with the mortal body, during mundane life, are liable; being unconsciously under its influence.

1911. The phenomena of mundane light being ascribed to the undulations of an ethereal fluid pervading the visible universe, (1831,) and electricity being ascribed to the polarization of the same fluid, so the spirits ascribe _their electricity_ and _their light_ to the undulation and polarization of an analogous ethereal fluid. It is to this ethereal fluid of the spiritual world, that the phenomena called odic belong, as I conceive. We may speak of that ether as the odic fluid, and we may designate the light and electricity which it produces as odic light, and odic electricity.

1912. But the use of the term force, as applied either to the ether appropriate to this mundane sphere, or to that which belongs more especially to the spirit world, seems to me erroneous. Imponderable fluids may be instrumental to forces, but, _per se_, cannot have force. No imponderable material fluid can _per se_ have any force, unless that of the reciprocal repulsion of particles, which causes their equable diffusion and resistance to condensation. Electricity has less force in proportion as it is more isolated. In vacuo it passes more diffusely and with less noise in proportion as the vacuum is more perfect. The violence of electrical phenomena is always dependent upon the reaction of the ponderable masses upon or between which it acts. In proportion as the matter on which it operates is more favourable to its condensation therein, or thereupon, the more violent is the deflagration or explosion which results. But in all the phenomena which have hitherto been recognised as the objects of strict physical examination, _vis inertiæ_ has been indispensable to the exhibition of force. “Give me but where to stand, and I will move the world,” was the exclamation of Archimedes; but the conviction thus expressed, of the necessity of a resisting basis, is universally recognised. In other words, there can be no action without reaction, whether chemical, mechanical, or muscular force be applied. Of course, it is preposterous to speak of an _isolated_ imponderable physical fluid, as possessing force _per se_. When left to itself it would remain inert, like any other inanimate matter. Clearly, isolated action on the part of such a fluid cannot be shown in any case whatever.

1913. Reichenbach alleged the substance or principle to which the name odic has been given to be visible, but he did not adduce any instance of its acting as a moving power so as to justify its being designated as the odic force.

1914. It is, however, unnecessary that those who admit the existence of an invisible ethereal medium through which, _without muscular contact_, or agency, effects are produced by will, should concur in their opinions respecting the nature of that imponderable principle. The question between those agreeing in the preceding principles, is whether it is to the will of mortals or to the will of disembodied spirits that such manifestations are to be attributed. I should think that no person who shall have read the communications which I have introduced into this work, as coming from my spirit friends, can ascribe those communications to the medium and myself. They must either suppose that there is a wilful manufacture of the wonderful and interesting information therein contained, setting aside the test conditions, through which they are sanctioned, as unreliable; or they must ascribe a wonderful fertility to the minds of the media and myself, through whom they have been obtained.

1915. So far from the ideas being obtained from my mind, which proceed from my spirit father, that he and I cannot come to one opinion on some points after much discussion. My father and sister have, by reiterated communication, as well established a conviction on my mind of their being that which they allege themselves to be, as if a correspondence had been carried on with them for the same space of time, say eighteen months, while they should be residing in another part of the country.

1916. But the whole superstructure built up by the most confident among the recent assailants of Spiritualism, Mahan, rests on the error already exposed in the case of its commission by Dr. Bell.

1917. It is assumed that spirits can never tell any ideas which do not exist in the minds of some persons present. Who was present when my spirit messenger conveyed to Mrs. Gourlay the request to send her husband to bank to inquire when a note would be due? Again, when cards were selected without the denomination having been seen by any mortal present, how could the denomination of the cards be spelt out upon the alphabetic disk?

1918. In his work, Mr. Mahan assumes that the odic force is identical with that which is the immediate cause of the spirit manifestations. Agreeably to the considerations above presented, no imponderable material principle, such as the ether of the undulation theory is supposed to be, can be a force. The only part which it can perform is that of being a medium of force. The fluid of electricity was never assumed to be a moving power, neither according to the Franklinian hypothesis of one fluid, nor that of two fluids, according to Dufay. Without chemical or mechanical disturbance, they would be as still as the water in a pond during a perfect calm.

1919. There is evidently, however, in nature, an imponderable cause of motion, and of other changes, more complicate than simple motion, and, I believe, only one such cause, and that is mind. No one who attributes the creation to the mind of the Creator, but must admit that the mind of the Creator and Ruler of the universe is the moving power of the universe. It must also be admitted that the mind of man, as a moving power, is very minute in comparison with that of its Author, or Source, but still resembling it so far as it reasons, and obeys the dictates of that reason, and causes matter to move in consequence of its designs, desires, wishes, or emotions.