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needle, making it point north and south, as if touched 

 by a loadstone. It will invert the polarity of a compass, 

 and make the north point turn to the south. At the 

 same time the ends of the needles are finely blued like 

 the spring of a watch. It will melt off the heads and 

 points of pins and needles, and sometimes the whole 

 surface of the needle is run, and appears, as it were, 

 blistered, when examined by a magnifying glass. It 

 will melt thin gold or silver, when held tight between 

 two panes of glass, together with the surface of the 

 glass itself, and incorporate them in a fine enamel. 

 Yea, a strong spark from an electrified phial makes a 

 fair hole through a quire of paper doubled, which is 

 thought good armour against the push of a sword, or 

 even a pistol bullet. And it is amazing to observe in 

 how small a portion of glass a great electrical force may 

 be. A thin glass bubble, about an inch diameter, being 

 half filled with water, partly gilt^ on the outside, when 

 electrified gives as strong a shock as a man can well 

 bear : allowing then that it contains no more fire after 

 charging than before, how much fire must there be in 

 the small glass ? It seems to be a part of its very sub- 

 stance. Perhaps if that fire could be separated from 

 it, it would be no longer glass. It might in losing this, 

 lose its most essential property, its transparency, brittle- 

 ness, and elasticity. 



Some have not improbably supposed, that all electric. 

 bodies, so called, are by their original constitution, 

 thoroughly saturated with electric fire: that it remains 

 fixed in them, (unless while the texture of those bodies 

 is quite altered by liquefaction) that fire fixed in a body 

 constitutes an electric > and all bodies where it is not fixed 

 are non electrics. Agreeably to which they suppose, 

 that in all non electricf 9 t\\e original fire loosely inhering, 

 is easily driven on bv the new collected fire, which then 

 possesses its place : but that in dec tries -the original fire 

 being impacted into their substance, and therefore more 

 firmly inhering, will uot give way to, or be driven on 

 by, the new collected fire'. Such is air in particular, 



