232 EXAMINATION OF VOLTA's EXPERIMENTS, &C. 



Expt. of copper Page 137, in the laft paragraph, it is faid, " If a piece of 

 and zinc joined, tt zinc to vv hj cn j s joined a piece of copper, and the zinc held 



and ihe copper to , J . \ , i • 



touch a zinc by two fingers or in any other manner, and the copper made 



condenfer, and « to touch the fuperior difc of the condenfer, which is zinc, 



afford — el. in „„,.,,./... . . . , , , 



this laft. while the interior is m communication with the ground, a 



" moment afterwards railing the upper difc in the air, it will 



Did not produce*, De negatively elearified." This I have always found the 

 — el. but + el. to . ' 



contrary, i. e. pofitive. 



Expt. of zinc p a g e 133^ paragraph three, it is alfo faid, " If the fuperior 



per condenfer, " difc °f tne condenfer be copper, and a piece of zinc be made 

 and affording no « to touch it immediately without any intervening fubftance, 

 •f nothing will be obtained, becaufe the zinc being then in 

 contact at the two oppofite ends with copper and copper, 

 " two equal forces act in oppofite directions, and by that 

 Did notfucceed." means deftroy or counterbalance each other." If the fupe- 

 rior difc was copper, I always found it negative, and if it was 

 zinc touched by a piece of copper, it was pofitive; both con^ 

 trary to Sig. Volta's aifertion. 



We find then that only one experiment out of three fucceeds, 

 which he calls fundamental, upon which his theory of galvaii* 

 ifm is founded. 

 The foregoing Knowing Sig. Volta's abilities both as a philofopher and ex- 



expts. were perimentalitf, I own I mention the refult of the foregoing ex- 



•ften repeated. r . .... x . , ° , 



penments (though it is after numerous repetitions) with much 



diffidence ; but the experiments are fo fimple, that it is almoft 



impoffible that I can have erred. 



By reafoning upon the phenomena, when copper and zinc 



are made to touch each other, it becomes eafily explicable by 



the old known laws of electricity. 



EXPLANATION. 



Explanation. In the firfl experiment, where zinc and copper are made 



In expt. I. either to touch each other, we find, on feparation, that the zinc has 

 or the copper r*- acquired a greater (hare of electric fluid than it had before the 

 felled the elecl. touch, and the copper lefs, by virtue of their mutual action upon 

 while in contact. each othef when ^ conta ^ > S o that the zinc mult have either 



attracted the electric fluid out of the copper, or the copper muft 

 have repelled it from itfelf into the zinc ; and that the firfl is 

 • the true caufe may be proved by connecting the copper difc 

 with conductors, and then touching it by the infulated zinc, 

 which will be found, on feparation, to be much more ftrongly 



pofitive 



