Part 19 (2/2)
1. Magnetism coincides with electricity in so many important points, that the existence of two magnetic ethers, as well as of two electric ones, becomes highly probable. We shall suppose, that in a common bar of iron or steel the two magnetic ethers exist intermixed or in their neutral state; which for the greater ease of speaking of them may be called arctic ether and antarctic ether; and in this state like the two electric fluids they are not cognizable by our senses of experiments.
When these two magnetic ethers are separated from each other, and the arctic ether is acc.u.mulated on one end of an iron or steel bar, which is then called the north pole of the magnet, and the antarctic ether is acc.u.mulated on the other end of the bar, and is then termed the south pole of the magnet; they become capable of attracting other pieces of iron or steel, and are thus cognizable by experiments.
It seems probable, that it is not the magnetic ether itself which attracts or repels particles of iron, but that an attractive and repulsive ether attends the magnetic ethers, as was shown to attend the electric ones in No. II. 9. of this Note; because magnetism does not pa.s.s through other bodies, as it does not escape from magnetised steel when in contact with other bodies; just as the electric fluids do not pa.s.s through gla.s.s, but the attractive and repellent ethers, which attend both the magnetic and electric ethers, pa.s.s through all bodies.
2. The prominent articles of a.n.a.logical coincidence between magnetism and electricity are first, that when one end of an iron bar possesses an acc.u.mulation of arctic magnetic ether, or northern polarity; the other end possesses an acc.u.mulation of antarctic magnetic ether, or southern polarity; in the same manner as when vitreous electric ether is acc.u.mulated on one side of a coated gla.s.s jar, resinous electric ether becomes acc.u.mulated on the other side of it; as the vitreous and resinous ethers strongly attract each other, and strongly repel the ethers of the same denomination, but are prevented from intermixing by the gla.s.s plane between them; so the arctic and antarctic ethers attract each other, and repel those of similar denomination, but are prevented from intermixing by the iron or steel being a bad conductor of them; they will, nevertheless, sooner combine, when the bar is of soft iron, than when it is of hardened steel; and then they slowly combine without explosion, that is, without emitting heat and light like the electric ethers, and therefore resemble a mixture of oxygen and pure ammonia; which unite silently producing a neutral fluid without emitting any other fluids previously combined with them.
Secondly, If the north pole of a magnetic bar be approached near to the eye of a sewing needle, the arctic ether of the magnet attracts the antarctic ether, which resides in the needle towards the eye of it, and repels the arctic ether, which resides in the needle towards the point, precisely in the same manner as occurs in presenting an electrised, gla.s.s tube, or a rubbed stick of sealing wax to one extremity of two skewers insulated horizontally on wine-gla.s.ses in the experiment ascribed to Mr. Canton, and described in No. IX. 1, of this Additional Note, and also so exactly resembles the method of producing a separation and consequent acc.u.mulation of the two electric ethers by pressing a cus.h.i.+on on gla.s.s or on sealing wax, described in No. 4 of this Note, that their a.n.a.logy is evidently apparent.
Thirdly, When much acc.u.mulated electricity is approached to one end of a long gla.s.s tube by a charged prime conductor, there will exist many divisions of the vitreous and resinous electricity alternately; as the vitreous ether attracts the resinous ether from a certain distance on the surface of the gla.s.s tube, and repels the vitreous ether; but, as this surface is a bad conductor, these reciprocal attractions and repulsions do not extend very far along it, but cease and recur in various parts of it. Exactly similar to this, when a magnetic bar is approximated to the end of a common bar of iron or steel, as described in Mr. Cavallo's valuable Treatise on Magnetism; the arctic ether of the north pole of the magnetic bar attracts the antarctic ether of the bar of common iron towards the end in contact, and repels the arctic ether; but, as iron and steel are as bad conductors of magnetism, as gla.s.s is of electricity, this acc.u.mulation of arctic ether extends but a little way, and then there exists an acc.u.mulation of antarctic ether; and thus reciprocally in three or four divisions of the bar, which now becomes magnetised, as the gla.s.s tube became electrised.
Another striking feature, which shows the sisterhood of electricity and magnetism, consists in the origin of both of them from the earth, or common ma.s.s of matter. The eduction of electricity from the earth is shown by an insulated cus.h.i.+on soon ceasing to supply either the vitreous or resinous ether to the whirling globe of gla.s.s or of sulphur; the eduction of magnetism from the earth appears from the following experiment: if a bar of iron be set upright on the earth in this part of the world, it becomes in a short time magnetical; the lower end possessing northern polarity, or arctic ether, and the higher end in consequence possessing southern polarity or antarctic ether; which may be well explained, if we suppose with Mr. Cavallo, that the earth itself is one great magnet, with its southern polarity or antarctic ether at the northern end of its axis; and, in consequence, that it attracts the arctic ether of the iron bar into that end of it which touches the earth, and repels the antarctic ether of the iron bar to the other end of it, exactly the same as when the southern pole of an artificial magnet is brought into contact with one end of a sewing needle.
3. The magnetic and electric ethers agree in the characters above mentioned, and perhaps in many others, but differ in the following ones. The electric ethers pa.s.s readily through metallic, aqueous, and carbonic bodies, but do not permeate vitreous or resinous ones; though on the surfaces of these they are capable of adhering, and of being acc.u.mulated by the approach or contact of other bodies; while the magnetic ethers will not permeate any bodies, and are capable of being acc.u.mulated only on iron and steel by the approach or contact of natural or artificial magnets, or of the earth; at the same time the attractive and repulsive powers both of the magnetic and electric ethers will act through all bodies, like those of gravitation and heat.
Secondly, The two electric ethers rush into combination, when they can approach each other, after having been separated and condensed, and produce a violent explosion emitting the heat and light, which were previously combined with them; whereas the two magnetic ethers slowly combine, after having been separated and acc.u.mulated on the opposite ends of a soft iron bar, and without emitting heat and light produce a neutral mixture, which, like the electric combination, ceases to be cognizable by our senses or experiments.
Thirdly, The wonderful property of the magnetic ethers, when separately acc.u.mulated on the ends of a needle, endeavouring to approach the two opposite poles of the earth; nothing similar to which has been observed in the electric ethers.
From these strict a.n.a.logies between electricity and magnetism, we may conclude that the latter consists of two ethers as well as the former; and that they both, when separated by art or nature, combine by chemical affinity when they approach, the one exploding, and then consisting of a residuum after having emitted heat and light; and the other producing simply a neutralised fluid by their union.
XI. _Conclusion._
1. When two fluids are diffused together without undergoing any change of their chemical properties, they are said simply to be mixed, and not combined; as milk and water when poured together, or as oxygen and azote in the common atmosphere. So when salt or sugar is diffused in water, it is termed solution, and not combination; as no change of their chemical properties succeeds.
But when an acid is mixed with a pure alcali a combination is produced, and the mixture is said to become neutral, as it does not possess the chemical properties which either of the two ingredients possessed in their separate state, and is therefore similar to neither of them. But when a carbonated alcali, as mild salt of tartar, is mixed with a mineral acid, they presently combine as above, but now the carbonic acid flies forcibly away in the form of gas; this, therefore, may be termed a kind of explosion, but cannot properly be so called, as the ethereal fluids of heat and light are not princ.i.p.ally emitted, but an aerial one or gas; which may probably acquire a small quant.i.ty of heat from the combining matters.
But when strong acid of nitre is poured upon charcoal in fine powder, or upon oil of cloves, a violent explosion ensues, and the ethereal matters of heat and light are emitted in great abundance, and are dissipated; while in the former instance the oxygen of the nitrous acid unites with the carbone forming carbonic acid gas, and the azote escapes in its gaseous form; which may be termed a residuum after the explosion, and may be confined in a proper apparatus, which the heat and light cannot; for the former, if its production be great and sudden, bursts the vessels, or otherwise it pa.s.ses slowly through them; and the latter pa.s.ses through transparent bodies, and combines with opake ones.
But where ethers only are concerned in an explosion, as the two electric ones, which are previously difficult to confine in vessels; the repulsive ethers of heat and light are given out; and what remains is a combination of the two electric ethers; which in this state are attracted by all bodies, and form atmospheres round them.
These combined electric atmospheres must possess less heat and light after their explosion; which they seem afterwards to acquire at the time they are again separated from each other, probably from the combined heat and combined light of the cus.h.i.+on and gla.s.s, or of the cus.h.i.+on and resin; by the contact of which they are separated; and not from the diffused heat of them; but no experiments have yet been made to ascertain this fact, this combination of the vitreous and resinous ethers may be esteemed the residuum after their explosion.
2. Hence the essence of explosion consists in two bodies, which are previously united with heat and light, so strongly attracting each other, as to set at liberty those two repulsive ethers; but it happens, that these explosive materials cannot generally be brought into each other's vicinity in a state of sufficient density; unless they are also previously combined with some other material beside the light and heat above spoken of: as in the nitrous acid, the oxygen is previously combined with azote; and is thus in a condensed state, before it is brought into the contact or vicinity of the carbone; there are however bodies which will slowly explode; or give out heat and light, without being previously combined with other bodies; as phosphorus in the common atmosphere, some dead fish in a certain degree of putridity, and some living insects probably by their respiration in transparent lungs, which is a kind of combustion.
But the two electric ethers are condensed by being brought into vicinity with each other with a nonconductor between them; and thus explode, violently as soon as they communicate, either by rupturing the interposed nonconductor, or by a metallic communication. This curious method of a previous condensation of the two exploding matters, without either of them being combined with any other material except with the ethers of heat and light, distinguishes, this ethereal explosion from that of most other bodies; and seems to have been the cause, which prevented the ingenious Dr. Franklin, and others since his time, from ascribing the powerful effects of the electric battery, and of lightning in bursting trees, inflaming combustible materials, and fusing metals, to chemical explosion; which it resembles in every other circ.u.mstance, but in the manner of the previous condensation of the materials, so as violently to attract each other, and suddenly set at liberty the heat and light, with which one or both of them were combined.
3. This combination of vitreous and resinous electric ethers is again destroyed or weakened by the attractions of other bodies; as they separate intirely, or exist in different proportions, forming atmospheres round conducting and nonconducting bodies; and in this they resemble other combinations of matters; as oxygen and azote, when united in the production of nitrous acid, are again separated by carbone; which attracts the oxygen more powerfully, than that attracts the azote, with which it is combined.
This mode of again separating the combined electric ethers by pressing them, as they surround bodies in different proportions, into each other's atmospheres, as by the gla.s.s and cus.h.i.+on, has not been observed respecting the decomposition of other bodies; when their minute particles are brought so near together as to decompose each other; which has thence probably contributed to prevent this decomposition of the two combined electric ethers from being ascribed to chemical laws; but, as far as we know, the attractive and repulsive atmospheres round the minute particles of bodies in chemical operations may act in a similar manner; as the attractive and repulsive atmospheres, which accompany the electric ethers surrounding the larger ma.s.ses of matter, and that hence both the electric and the chemical explosions are subject to the same laws, and also the decomposition again of those particles, which were combined in the act of explosion.
4. It is probable that this theory of electric and magnetic attractions and repulsions, which so visibly exist in atmospheres round larger ma.s.ses of matter, may be applied to explain the invisible attractions and repulsions of the minute particles of bodies in chemical combinations and decompositions, and also to give a clear idea of the attractions of the great ma.s.ses of matter, which form the gravitations of the universe.
We are so accustomed to see bodies attract each other, when they are in absolute contact, as dew drops or particles of quicksilver forming themselves into spheres, as water rising in capillary tubes, the solution of salts and sugar in water, and the cohesion with which all hard bodies are held together, that we are not surprised at the attractions of bodies in contact with each other, but ascribe them to a law affecting all matter. In similar manner when two bodies in apparent contact repel each other, as oil thrown on water; or when heat converts ice into water and water into steam; or when one hard body in motion pushes another hard body out of its place; we feel no surprise, as these events so perpetually occur to us, but ascribe them as well as the attractions of bodies in contact with each other, to a general law of nature.
But when distant bodies appear to attract or repel each other, as we believe that nothing can act where it does not exist, we are struck with astonishment; which is owing to our not seeing the intermediate ethers, the existence of which is ascertained by the electric and magnetic facts above related.
From the facts and observations above mentioned electricity and magnetism consist each of them of two ethers, as the vitreous and resinous electric ethers, and the arctic and antarctic magnetic ethers. But as neither of the electric ethers will pa.s.s through gla.s.s or resin; and as neither of the magnetic ethers will pa.s.s through any bodies except iron; and yet the attractive and repulsive powers accompanying all these ethers permeate bodies of all kinds; it follows, that ethers more subtile than either the electric or magnetic ones attend those ethers forming atmospheres round them; as those electric and magnetic ethers themselves form atmospheres round other bodies.
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