and Electrolysis of Chemical Compounds. 445 



its hydrogen for potassium and sodium*, and, in alcoholic 

 solution, also for copper, gold, &c. ; indeed chloride of gold is 

 violently attacked, hydrochloric acid being liberated, and still 

 more violently the oxide of gold, at ordinary temperature. 

 Amy lie alcohol scarcely gives passage to the current of 950 

 Bunsen elements, although potassium and sodium expel its 

 hydrogen. 



The transmission of induction-currents through liquids is a 

 very complicated phenomenon, in which it is often difficult to 

 decide whether electrolysis has taken place, or whether merely 

 the thermal action of the spark-discharge has split up the 

 compound. The electrodes may be placed so far apart that 

 the induction-current (in truth, only the opening-current) 

 will be transmitted without any spark-discharge, and a sensi- 

 tive galvanometer show a deflection (in methylic iodide, for 

 instance, in which a great rise of temperature was at the same 

 time perceptible) ; or with the electrodes at a less distance 

 from one another, spark-discharges will take place (as in the 

 ally lie compounds, in which carbon will then be deposited), 

 and during these the needle will be deflected. The peculiar 

 conduction previously mentioned, in which a wave-like motion 

 of the liquid accompanies the transmission of the induction- 

 current |, makes its appearance also in amylic sulphide and 

 in toluol : in brombenzol and allylic sulphide only the longer 

 electrode is put into vibration ; while in bromtoluol nothing 

 of the kind was to be observed with the distance of 1 millim. 

 between the electrodes, although this substance is a very bad 

 conductor. In naphthaline a spark of 70 millims. will not 

 burst through. Accordingly this kind of discharge appears 

 to occur only at a certain degree of insulation. 



On the whole, then, the chemical properties here give no 

 measure for the conductivity ; from them no conclusion can 

 be drawn a priori respecting the latter. 



9. Experiments with Warren De la Rue's Chloride-of-silver 

 Battery of 8040 elements and some very badly conducting 

 Compounds %. 



Notwithstanding the foregoing experiments it still remains 

 an open question whether on employing very much more 

 powerful currents conduction and decomposition would not 



* Mercaptan with mercuric oxide produces ethyl-sulphide of mercury; 

 this compound is readily fusible, and conducts the current of 20 Bunsen 

 elements (galvanometer-deflection 3°). 



t In Table ILL with triethylamine, and Table V. with mercury-methyl, 

 where the electrodes were still 4 millims. apart. 



\ See a brief account of these results in the Proceedings of the Koyal 

 Society, vol. xxv. p. 322 (1876). 



