TRANSACTIONS OF THE SECTIONS. 33 



Sixth fact. 



A piece of iron wire was connected with each of the poles of a pile, 

 and each of these pieces made to plunge into a separate vessel filled 

 with common water, both vessels being connected by the means of a 

 piece of platina. That part of the negative polar wire which was im- 

 mersed in water did not rust at all, as long as there was a current 

 passing through the arrangement. 



Seventh fact. 



Copper being intimately associated with zinc^ and brought into an 

 aqueous solution of chloride of sodium in such a manner that each of 

 the metals did plunge into a separate vessel, was soon chemically 

 affected; provided, however, both vessels were not communicating 

 with each other. 



Eighth fact. 



The same experiment was made as in the preceding case, with the 

 difference however that both metals did plunge into the same vessel. 

 Under these circumstances the copper piece was not in the least cor- 

 roded by the salt water, whatever was the length of time during which 

 I kept the metals immersed. 



Ninth fact. 



A piece of copper was connected with each of the poles of a vol- 

 taic pile, and put into a vessel holding an aqueous solution of common 

 salt. Both pieces were attacked by the fluid, just in the same way as 

 if they had not been attached to a voltaic arrangement, provided both 

 vessels did not communicate with each other. 



Tenth fact. 



The experiment was made as in the preceding case, with the dif- 

 ference only that both vessels were caused to communicate with each 

 other by the means of a piece of platina. The positive polar wire 

 quickly underwent oxidation, whilst the negative one remained un- 

 touched. If an aqueous solution of common salt was made use of as 

 the exciting fluid in the pile, and the latter left unclosed, the copper 

 pieces of the voltaic pairs rather readily entered into oxidation, whilst 

 they were not at all chemically affected when the pile was closed. 



Eleventh fact. 



A piece either of copper or of iron was connected with each of the 

 poles of a pile ; two tumblers were filled, partly with mercury, partly 

 with water, or with a solution of common salt, and both vessels made 

 to communicate with each other by a piece of platina, so as to make 

 each extremity of the latter enter into the mercury of either vessel. 

 Things having been arranged in the manner described, the polar wires 

 were introduced, each of them into one of the tumblers, so that the 

 free end of each wire was made to plunge into the mcrcurv. Under 



1839. n 



