202 Reply to Mr. De Luc. 



room, yet, when brought into an air containing a greater alsohde 

 quantity of electricity, they became relatively negative. Now, 

 it' this admit of a different explanation, the necessity of the above 

 inference is destroyed : it is therefore of importance to try if this 

 can be effected. 



With regard to my experiment in which bodies possessed of 

 similar states attract each other ; Mr. De Luc considers that 

 the excited electric repelled the similar electricity of the pith 

 ball through the thread into some other part : the effect is owing 

 to wliat Volta calls electric influence, and it appears to consti- 

 tute an essential part of his system. But with this I have been 

 long familiar; not as belonging to Volta, but to Franklin. Now 

 it appears to me, t'lat this principle of electric inlhiences may be 

 applied in explanation of Mr. De Luc's experiment on electrified 

 air. The balls in the natural state are brought into a positive 

 atmosphere ; the electricity of the latter repels the natural quan- 

 tity of the balls into their internal substance : the external parts 

 are therefore left minus. With this view, the secpiel exactly cor- 

 responds ; for, when the Iialls were brought back into the un- 

 electrified room, they collapsed into their natural state. But, 

 on the opposite view, the balls by immersion into a positive at- 

 mosphere should assume that state, and retain it when removed, 

 and therefore still continue to diverge. Hence it would appear 

 to me that the experiment is an anomaly on the h\^othesis of 

 Volta, and perfectly reconcileable to the principles of Franklin. 



But my experiment above referred to, in which bodies of a 

 similar state attracted each other, does not in my mind appear 

 to be explained by the principle of electric influences. Mr. De 

 Luc supposes that the excited tube repels the electricity of the 

 bail through its thread, leaving it ultimately negative, and there- 

 fore attracting it. But at the moment when this attraction is 

 about to take place, if the tube be dexterously removed, it will 

 be found that the ball is still positive. 



Furthermore, it is for Mr. De Luc's consideration, whether the 

 principle of electric influences be even applicable to this experi- 

 ment. Volta's principle, if I understand it, relates to two bodies, 

 one of which is in the natural state, and the other in a super- 

 natural state. In my experiment they are both in a supernatural 

 state. 



^^'Uh regard to the explanation of the motion of electrified 

 bodies given by Volta, and cited by Mr. De Luc, p. 99, I need 

 only observe that it virtually destroys the principle of repulsion, 

 and refers all to attraction. How then can it be at the same 

 time supposed that electricity is an elastic fluid ? 



The experiment which I consider subversive of Franklin's sup- 

 posed imj)ermeability of glass, appears to Mr. De Luc explicable 



by 



