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Show 6+ Additional Notes. the best conductor ·, and next to these water, and all other moist bodies· but it was Jatc1y disco\'ered, that dry char oal, recently burnt, was a 1~10re perfect conductor than metal ; and it appear from the experiments discO\'Crcd by Galvani, which have thence the name of Galvanism, that animal fle h, and particularly perhap the nerves of animals, both which are composed of much carbon and water, arc the most perfect conductors yet discovered; that is, that th y give the least re istance to the junction of the spontaneous electric atmospheres, which exist round metallic bodi es, and which differ very l ittle in respect to the proportions of their vitreous and resinous in gredients. Thus also thono-h where the accumulated electricities arc dense, ' b as in charging a coated glass-jar, the glass, which intervenes, may be of considerable thickness, and may still become charged by tile stronger attraction of the secondary electric ethers; but where the spontaneous adhesive electric atmospheres are employed to charge plates of air, as in the Galvanic pile, or probably to charge thin animal membranes or cuticles, as perhaps in the shock given by the torpedo or gymnotus, it seems necessary that the intervening noncondu cting plate must be extremely thin, that it may become charged by the weaker attraction of these small quantities or difference of the spontaneous electric atmospheres ; and in this circumstance only, I suppose, the shocks from the Galvanic pile, and from the torpedo and gymnotus, differ from those of the coated jar. 3. When atmospheres of electricity, which do not differ much in the quantity or proportion of their vitreous and resinous ethers, approach each other, they are not easily or rapidly united; but the predominant vitreous or resinous ether of one of them repels the similar ether of the opposed atmosphere, and attracts the contrary kind of ether. The slow11ess or difficulty with which atmospheres, which differ but little in kind or in density, unite with each other, appears not only from the experiment of Mr. Canton above related, but also from the repeated smaller shocks, which may be taken from a charged coated jar after the first or principal discharge, if the conducting m·edium has not been quickly removed, as is also mentioned above. Chemical Theor11 o~'El t. · · .:1 v ec ?lctty and liiagneti m. 6S Hence those atmo pheres f 'tl 1 . · d. ff . b . , o ei ler {llld of electric matte 1 . h J ei ut very ltttle from each other in I ind . . r,. w lie most perfect conductors to c· th . 01 quantity, reqlilre the ause em to umte. Thus it a) . I l\1r. Bennet's doubler, as mentioned in the Preliminar. p I pea~ s_ >y No. VI: t hat the natural adhesive atmosnhere round ~~ ~oposJt~~n, more t . I · · • SI ver con tams h. VL 1 eous c ectnctty than that naturally round zinc. 1 t I t m plates of the e metals, each about au ounce in weigh~ J.u. Wll~~ ont eac~l oth er, or moc~crately pressed together, their atmo~p;:~:es ~o :~hc~·mtc. For metal_ltc plate '. which when laid on each other, clo not 1 e, cannot be salCl to be m real contact of 1 . 1 tl . ~ . · . ' ' w 11c 1 1eu· not acl-termg lS a yroof; and m consequence a thin plate of air or of th . <>wn repulsive ethers exists between them. ' eJr .. I~ence when two plates of zinc and silver arc thus brought in to the V· JCimty .o f each other, the plate of air between tl1 em, as t1 1 ey are not In adhestve contact, becomes like a charo·ed coated · . d ·f 1 . b Jar, an 1 t 1ese two metallic plates are touched by your dry hands tl d · tl · 1 · · · ' 1ey o not umte 1e1r e ectncJtlCs, as the dry cuticle is not a s uffic1 ' entl l d . . · y gooc con-uctoi, but If.onc of the metals be put above, and another under th tongue, the sahva and moist mucous membrane, muscular fibres, an~ nerves,_ supply so good a conductor, that this very minute electric shock 1s produced, and a kind of pungent taste is perceived. ':hen a plate or pencil of. silver. is put between the upper lip and the _gum~ and a _plate. or pencil of zmc under the tongue, a sensation of light IS perce1ve<.1 m the eyes, as often as the exterior extremities of these metals are brought into contact; which is owino· in like manner to the discharge of a very minute electric shock, w11i~11 would not have been produced but by the intervention of such good conductors as moist membranes, muscular :fibres, and nerves. · In this situation, a sensation of lio-ht is produced in the eyes· wh 1' ch seems to show, that these ethebr s pass throuo-h nerves more' '1 b eas1 y, than through muscular flesh simply; since the passage of them through the retina of the eyes from the upper gum to the parts beneath the tongue is a more distant one, than would otherwise appear necessa:y· It is not so easy to give the sensation of light in the eyes by passmg a small shock of artificially accumulated electricity through the eyes (though this may, I believe, be done) because this artificial K |