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V. Second Rfply to Mr. De Luc's Observations on a Paper 

 entitled " Rejitctions on the Inadequacy of the principal 

 Hypotheses to explain the Phcenomena of Electricity." By 



M. DoNOXAN, Es(J. 



To Mr. Tilloch. 



Sir, — In my former reply to Mr. De Luc, I declared that I 

 had no intention of supporting any electrical hypothesis; on the 

 contrary, I wished to show that we are deceived when we sup- 

 pose ourselves possessed of any knowledge on the subject heyoi:d 

 facts. I did not intend to affirm that Mr. De Luc's experimeut, 

 in which unelectrifted pith-halls brought into a positive atmo- 

 sphere appeared negatively electrified, could he justly explain«d 

 by the hypothesis of Franklin ; inasmuch as I conceived this hy- 

 pothesis to be itself unfounded ; but merely that it had as good 

 claims as any other. My intention was to show that even Volta';- 

 doctrine is untenable, and that Mr. De Luc's experiment brought 

 forward in support of it, is better explicable on the views o" 

 Franklin, even tijough the Fraiiklinian system is in general er- 

 roneous, than on the views of Volta: and therefore, that the ex- 

 periment in ({ue>tlon did not estaljlish the opinions of the latter 

 philosopher. My reasons for supposing this I have stated to be 

 as follows. When the unelectrifted balls were brought into a 

 room where a powerful electric machine was dispersing positive 

 electricity, they diverged negatively; and this I conceived might 

 as well be explained by the agency of electric injluences, as an 

 experiment of mine in which similarly electrified bodies attracted 

 each other, and w'lich Mr. De Luc accounts for by the same in- 

 fluences. I therefore considered that I had an equal claim to 

 sup])ose the positive atuiosplieie to liave lepeiled the natural 

 electricity of the balls into their interior substance, and virtually 

 to have left the exterior minus. With this I considered the se- 

 quel to correspond. When the balls were removed into the un- 

 clectrified room, thev lost their divergence, because the cau'-e 

 which induced tlie minus state in the balls beiiig removed, the 

 (juautlty natural to the balls might receive its former distribu- 

 tion, and therefore appear in the natural state. But in using 

 the expression natural state, I liave not made myself understood 

 to Mr. De Luc. 1 did not mean the natural state as laid down 

 bv Franklin. I conceived, even admitting tiie standard natural 

 state assumed by Volta, that tlie balls should resume their non- 

 c'f'ctrified appearance. For admit this standard to be variable, 

 is it probable that there was any variation in so short a period 

 as that occupied by the experiment, when it appears that the 

 balls had not time to absorb any electricity from tlie positive at- 

 mosphere ; 



