66 



tervening air betwixt i+self and the iron. The air thus 

 1 repelled, the intervening space, says that philosopher) 

 became a vacuum ; and the? iron, finding io resistance 

 approached witn an impulsive force, pushed on hy the 

 air. behind it." Plutarch likewise is of the same 

 o ( inioii He says, "amber attracts none of those 

 things tha*- are brought, to it, any more than the load- 

 stone. That stone emits a matter, which reflects th 

 circiim -ambient air, and thereto} forms a void. That 

 'expelled air puts in motion the air b fore it, which 

 making a circle returns ^to the void space, driv ng 

 before it, towards the I adstbne, the iron which it 

 ineets-in its way/' He tiien proposes a difficulty, 

 <c why ihe vortex which circulates round trie loa^l* one, 

 does not make its waj to wood or stun * as \\ eil as 

 iron," He answers, like Descartes, that * the pores 

 of iron have an analogy to the panicles ol the vor^ 

 circulating about the loadstone, wi.ich yields them, 

 such access as they can find in no other bodies, whoas 

 pores arc diffurently formed," 



13. It is scarce credible, that the real cause of elec- 

 tricity was known to the ancients, though there be in- 

 dications of it in the work of 'I imae s Locrensis, 

 concerning the soul of the world, a respectable mo* 

 nument of ancient philosophy. It is une, ihat mo. 

 tlcrn naturalists themselves are divided on (hi. point, 

 not indeed with the respect to the general cau-s ^ of 

 clectricity 5 butwith regard to the causes of ttie different 

 directions of the electric matter. They do not indeed 

 say wherein the essence of this matter consists ; they 

 only define it by its properties, and explain it by its 

 effects ; yet all own, that it is a very subtle 11 aid, re 

 siding around electric bodies, which upon being put 

 into motion by the friction of those bodies, or any 

 other cause, forcibly rushes into them, carrying along 

 with it all the minute things contained in its vortex, 

 and producing all the other effects of electricity which 

 we perceive : now this is precisely what Timseus says 

 of it, in giving the reason Camber's attracting bodies^. 



