Chemical Theory of Electricity and Magnetism. 49 



4. Glass holds within it in combination much resinous electric 

 ther, which constitutes a part of it, and which more forcibly attracts 

 vitreous electric ether from surrounding bodies, which stands on it 

 mixed with a less proportion of resinous ether like an atmosphere, 

 but cannot unite with the resinous ether, which is combined with 

 the glass; and resin, on the contrary, holds within it in combination 

 much vitreous electric ether, Avhich constitutes a part of it, and 

 which more forcibly attracts resinous electric ether from sun-round- 

 ing bodies, which stands on it mixed with a less proportion of vitreous 

 ether like an atmosphere, but cannot unite with the vitreous ether, 

 which is combined with the resin. 



As in the production of vitrification, those materials are necessary 

 which contain much oxygen, as minium, and manganese; there is 

 probably much oxygen combined with glass, which may thence be 

 esteemed a solid acid, as water may be esteemed a fluid one. It is 

 hence not improbable, that one kind of electric ether may aiso be 

 combined with it, as it seems to affect the oxygen of water in the 

 Galvanic experiments. The combination of the other kind of electric 

 ether with wax or sulphur, is countenanced from those bodies, when 

 heated or melted, being said to part with much electricity as they cool, 

 and as it appears to affect the hydrogen in the decomposition of water 

 by Galvanism. 



5. Hence the nonconductors of electricity are of two kinds; such 

 as are combined with vitreous ether, as resin, and sulphur; and such as 

 are combined Avith resinous ether, as glass, air, silk. But both these 

 kinds of nonconductors are impervious to either of the electric 

 ethers; as those ethers being already combined with other bodies 

 will not unite with each other, or be removed from their situations 

 by each other. Whereas the perfect conducting bodies, as metals, 

 water, charcoal, though surrounded with electric atmospheres, as they 

 have neither of the electric ethers combined with them, suffer them 

 to permeate and pass through them, whether separately or in their 

 neutral state of reciprocal combination. 



But it is probable, that imperfect conductors may possess more or 

 less of either the vitreous or resinous ether combined with them, 



H 



