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BENJAMIN FRANKLIN 



1706-1790 



Benjamin Franklin, representative of the rationalist tendencies 

 of the eighteenth century, zvas born in Boston, January i/, 1/06. 

 His early life and political missions are intimately related in his 

 ''Autobiography," a classic in American literature. Apart from his 

 political services to the cause of American independence, he attained 

 distinction in the field of scientific researches and experiments. In 

 1746 he began the experiments in electricity which resulted in his 

 identification of electricity with lightning. He died in Philadelphia, 

 April ly, 1790. 



THE IDENTITY OF LIGHTNING AND ELECTRICITY * 



But points have a property, by which they draw on as well as 

 throw off the electrical fluid, at greater distances than blunt bodies 

 can. That is, as the pointed part of an electrified body will dis- 

 charge the atmosphere of that body, or communicate it farthest to 

 another body, so the point of an unelectrified body will draw off the 

 electrical atmosphere from an electrified body, farther than a blunter 

 part of the same unelectrified body will do. Thus, a pin held by 

 the head, and the point presented to an electrified body, will draw off 

 its atmosphere at a foot distance; where, if the head were presented 

 instead of the point, no such effect would follow. To understand 

 this, we may consider, that, if a person standing on the floor would 

 draw off the electrical atmosphere from an electrified body, an iron 

 crow and a blunt knitting-needle, held alternately in his hand, and 

 presented for that purpose, do not draw with different forces in 

 proportion to their different masses. For the man, and what he holds 

 in his hand, be it large or small, are connected with the common 

 mass of unelectrified matter ; and the force with which he draws 



* From Franklin's correspondence with Peter Collinson, July 29, 1750. 

 Works of Benjamin Franklin, Philadelphia, 1809, Vol. IH, pp. 45-49. 



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