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enables me to see, and know all things around us ? 

 I mean light. How is it communicated to us? 

 Does it flow in a lucid river, in a continued stream 

 from the orb of the sun to the earth 1 Or does the 

 sun impel those particles only which are contiguous 

 to his orb, which impel others, so on and on, to the 

 extremity of his system? Again ; Are the particles 

 of light, naturally and essentially lucid? Or only 

 by accident, when they are collected ? Or when put 

 into motion ? Yet again, does light gravitate or 

 not 1 Does it attract other bodies, or repel them 1 

 Is it the strongest, or the only repellent in nature ; 

 and what communicates that power to all repellents 

 in, nature ? Is this power the same with electricity, 

 or wherein does it differ therefrom ? Is light sub- 

 ject to the general laws, which obtain in all other 

 matter? Or is it a body, sui generis, altogether 

 different from all other bodies ? Is it the same, or 

 how does it differ from ether ? Sir Isaac Newton's 

 subtle matter ? What is etker * Wherein does it 

 differ from the electric fluid ? Who can explain 

 (and demonstrate the truth of his explanation) the 

 phenomena of electricity ? Why do some substances 

 co?iduct the electric matter, and others arrest its 

 course ? Why does a globe of glass, and another of 

 sulphur, just counteract each other? Why is the coated 

 phial capable of being charged just to such a point, 

 and no farther? O Crux Pkilosophorum ! Super- 

 abundant proof of the shortness of hum-Mi know- 

 ledge! 



