318 NEW CLASSES OP GALVANIC CONDUCTORS. 



chain is not af- chemical effect will be perceived, the insulation of the 



fected . . 



even if a wet positive wire being an insurmountable obstacle to it. If 



conductor be in now a little sponge, or a piece of cloth, be wetted with 



contact with ' , , , . r , , . , , 



the soap and water, and placed in contact both with the negative wire 



negative wire, and the soap, every thing will remain as before, and there 



But the circle w ill be no trace of chemical decomposition. But the mo- 



is completed by ■ _, '. . . , , 



the least wet "lent. this wet conductor is so placed, as to touch at the 



between the same time the positive wire and the soap, gas will be ex- 

 soap and posi- . 

 tive wire. tncated in torrents, and the electrometers will indicate the 



completion of the galvanic circle. Thus the smallest quan- 

 tity of water is sufficient, to destroy at once the anomaly 

 of insulation, which characterizes this substance, and con- 

 vert it wholly into an excellent conductor. I have fre- 

 quently seen this effect result from the simple application 

 A coin damped of a piece of money, which I had damped on one side 

 on one si e. mere py by breathing on it, and which I afterward placed 

 on the surface of the soap, and in contact with the positive 

 wire ; while the same piece of metal, in the very same 

 position, produced no effect in its usual state of dryness. 

 No fluid but I know no fact, where the indispensable necessity of 



watei produces wa £ er [ n a galvanic action declares itself in a more astonish- 

 this effect 5 



ing way : for the property of converting the whole mass of 



soap into a perfect conductor for the two poles in com- 

 munication, by the contact of the positive wire, belongs 

 exclusively to water, and is not, as might perhaps be sup- 

 posed, a property of fluidity in general. Mercury, naph- 

 tha, oils of every kind, and other liquors not aqueous,, 

 poured into a hollow made in the soap at the spot where 

 the positive wire is inserted, produce not the least effect, 

 anditisdecom- It is very remarkable too, that water thus applied between 

 process? * ne posi { i ve wire and the soap undergoes the same chemical 



decomposition as in the apparatus for decomposing it. In 

 fact, according to the nature of the metallic wire, with 

 which the water or wet conductor is in contact, either an 

 oxide will be produced in abundance, or a gas, which is 

 so that the ef- easily discernible by the froth it occasions. Hence it is, 

 he^alTthe tna *- tne imc curing which the interposed water produces 

 water i^ de- its effect is always limited, being in the direct ratio of the 

 corrtpose . quantity employed, and the inverse ratio of the intensity 



of the pile: but in all cases both the elcctrometrical and 

 v chemical 



