MR. WILSON OX ELECTRICITY. J |'^ - 



1 think the following experiments will put this beyond a 

 doubt: I. I faftened a piece of card into a iWck of glafs, and An Infulated 

 then rubbed it over with flrone: ffum water and covered it with J^^el ot card, 



-,..,. /•,.,• , •. , 1 r i- - f faced with zinc 



fiUngs or zmc; lo that when it was dry, it had a lurface ot filings was ufed 



filings of zinc. From a heap of the fame filings I took up as^^P'^^r zinc 



much as 1 could on this little (llovel without touching it with bright piate of 



any thing elfe, and let them fall very flowly upon a piece of copper. 



bright llieet copper faftened in an inclined pofition upon the 



cap of an eledlrometer, and formed into a receptacle at its 



lower part to contain the filings. In this operation almofl The copperplate 



every particle of filings ireceffarily came in conta6l with the ^^^^^"°^ *^'"'^"" 



face of the copper. After letting fall upon the copper about 



an ounce and a half of filings there was not the leafl fenfible 



efFeft on the eleflrometer. 2. I then took a piece of the fame A copper fievc 



flieet copper, which was pierced full of fmall holes, and ^'f^^ed J^^^*^*^*^"* "^^^ 



through it the fame filings I had ufed in the above experiment, fhovei. 



upon the fame copper on the eledtrometer, and the gold leaves The copperplate 



diverged with pofitive eledricity and difcharo^ed themfelves ^^^j .^''^"S'y 



. "^ poljtive, 



againft the flips of tin foil on the infide of the glafs ten times 



before the whole of the ounce and half of filings were ftfted 



into it. 



Now, fince the feparating the two metals from contaft in Separation was 



the fecond of the above experiments is the only difference be*.^!?"^. ^^^ ""^^ 

 , , , , or this elefilri- 



tween them, and as the eleclnc fluid was excited only in the city. 



fecond, I think we may fafely conclude that that feparation was 



the caufe of the excitation, and not touching. 



I am very much inclined to believe that the excitation that Eledrlc excltt- 



takes place in fri6lion is caufed by the fame circumflance, and ^'°:" '^ probably 



that the fridion does nothing more towards the excitation than kind, 



bring the different p^rts of the fubflance that are rubbed to- 



gctlicr into contact, and feparate them from it. 



I am your obedient humble fervanf, 



WILLIAM WILSONT. 



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