VON GUERICKE S EXPERIMENTS. 40 1 



linen line to a "pointed stick." He had before stated 

 that points, even a person's nose, best attracted the float- 

 ing electrified feather. Having found out the discharging 

 advantage of the point, he thus applies it as the best means 

 of causing the virtue to pass upon the linen thread. 



This is one of the most remarkable examples of thought- 

 ful invention which the history of electricity affords. He 

 conceived the idea that the electrical virtue could be made 

 to pass over a line; that the charge could be imparted to 

 a thin thread conductor by connecting the latter to the 

 sharpened extremity of a fixed support; that the support 

 could be electrified by bringing the rubbed globe into 

 proximity with it; that the end of the hanging thread 

 would, when electrified, move toward and from an adja- 

 cent fixed body, and that therefore a movement to and fro 

 of the excited globe at one end of the line would instantly 

 cause a like vibratory motion of the other end. 



And yet von Guericke had never heard of "Maxwell's 

 laws," or "surface density," or "ether strains and 

 stresses;" but he lived in the seventeenth century, and 

 therefore it is conceivable that he may have made the dis- 

 coveries above outlined. Had he lived in the nineteenth, 

 plenty of people would be ready to argue the opposite, for 

 to these doubting minds no man can now be presumed to 

 have discovered anything if, after the event, it is objected 

 that he was ignorant of the laws which higher intelli- 

 gences think they would have followed had they made the 

 discovery themselves. Besides, there would not be want- 

 ing other keen spirits to recognize a complete anticipa- 

 tion of his revelation of electrical conduction in Bacon's 

 allegation of half a century before, that "it is an ancient 

 tradition everywhere alleged, for example, of secret prop- 

 erties and influxes, that the torpedo marina, if it be 

 touched with a long stick, doth stupefy the hand of him 

 that toucheth it." * 



1 Bacon: Nat. Hist. Cent., x.,.No. 993. 

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