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Show 70 Additional Notes. 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 etl1er, which resides in the needle towards the point, precisely in the same manner as occurs iti presenting an electrised glass tube, or a rubbed stick of sealing wax to one extremity ·of two skewers insulated horizontally on wine-g·lasses in the experiment ascribed to 1\fr. Canton, and described in No. IX. 1, of this Additional Note, and also so exactly resembles the method of producing q. sepa1 ation and consequent accumulation of the two electric ethers by pressing1a cushion on glass or on sealing wax, described in No. '1 of this N otc, that their analogy is evidently apparent. Thirdly, \\Then much accumulated electricity is approached td' one end of a long glass 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 glass tube, and repels the vitreous ether; but, as this surface is a bad contluctor, 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 glass is of electricity, this accumulation of arctic ether extends but a little way, and then there exists an accurn ulation of antarctic ether; and thus reciprocally in three or four divisions ·of the bar, whicl.1 now becomes magnetised, as the glass 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 comm6n mass of matter. The eduction of electricity from the earth is shown by an insulated cushion soon ceasing to supply either the vitreous or resinous ether to the whirling globe of glass or of sulphur; the eduction of magnetism from ·the earth appears from the Chemical Theory of Electricity and Jviagnetisrn. 71 following experiment: if. b f . . this part of the world i~ bar o ITO~ be set up~·Jght on the earth in \ . 1 ' ecomes In a short time mao·nef I· th ' ower end possessino- northern 1 't . o ICa' e hi her end i o p~ an y, or arctic ether, and the . hg . n consequence possessHlg southern polarity or a t t. et er; wh1ch b ll . . n arc IC ~ay _e we explamed, If we suppose with Mr. Cavallo that the earth Itself IS one great mao·net ·with "t th . . ' t . 1 r:, , 1 s sou etn polanty or an arctic et 1er at the northern end of its a . . . d . th' t. . xrs' an ' m consequence a It attr~cts the arctic ether of the irou bar into that end of it whicl~ touches the earth, and repels the antarctic ethel· of' tlJe . b 1 tl d · J ron ar to t 1e o. 1_er _en of tt, ~xactly the same as when the southern ole of ai a1 t1ficml magnet Is brot1ght i1Jto contact with one end p 1 needle. of a sewing 3 .. The magnetic and electric ethers agree in the characters above mentwn~d, and l~erhaps in many others, but differ in the following · ones. 1he <.:lectnc ethers pass readily throuo·h metallic aqueo d ·1 · b I' o , us, an Cal J0111C Ot tes, but do not permeate vitreous or resinous ones. though on the surfaces of these they are ca1)ab1e of adlJCritJo- 1 f' b · 0 , anc o emg accu~llllated by _the approach or contact of other bodies; while th ~ n~agnet1c ethers wlll no~ permeate any bodies, and are capable of berng accumulat~d ?nly on 1ron and steel by the approach or contact of nat~ral or artrfic1al magnets, or of the earth; at tbe same time the attractive and repulsive powers both of the mao·netic and electric ethers will act througl1 all bodies, like those of gra:itation and heat. Secondly, The two electric ethers rush into combination, when they can approach each other, after having been separated and conde~ sed, and prod~ce a violent explosion emitting the heat and light, whtch were prevwusly combined with them; whereas the two mao·netic ethers slowly combine, after having been separated and acc~mulated on the opposite ends of a soft iron bar, and without emitting heat and light produce a neutral mixture, which, like tbe electric combination, ceases to be cognizable by our sense· or experiments. Thirdly, The wonderful property of the magnetic ethers, when separately accumulated on the ends of a needle, eudeavouring to approach the two opposite poles of the earth; nothing similar to whi ch has been obscrv·ed in the electric ethers. From these strict analogies between electricity anJ magne tism, |