and Electrolysis of Chemical Compounds. 451 



at which decomposition takes place ; so that there is no valid 

 reason for ascribing the increased conductivity to the weak- 

 ening of chemical affinity by heat ; and. yet the molecules 

 must here encounter one another at least as frequently as in 

 a compound liquid at ordinary temperatures. 



It is also difficult, if solution is a necessary condition for 

 electrical conductivity, to imagine compounds already elec- 

 trolyzed in the solid condition, such as the haloid compounds 

 of lead *, oxide of zinc, sulphide of antimony, and realgar f , 

 in the electrolysis of which the zinc and sulphur separated 

 ignite in the air. 



The opinion has been expressed, that, on applying extremely 

 intense electromotive forces, even those compounds which are 

 insulating to the current of an ordinary galvanic battery 

 would assume an electrolytic conduction. But the highly 

 intense current from Warren De la Rue's chloride-of-silver 

 battery does not effect any evident electrolysis of the com- 

 pounds which had shown themselves the most insulating, but 

 leaves it doubtful. Still, from the undulatory motion of the 

 liquid, a real transmission of electricity must be inferred. I 

 have succeeded in bringing about the same phenomena by 

 means of moderate currents from a Ruhmkorff's induction- 

 coil, as well as by the discharge-current of a powerful elec- 

 trical machine, in liquids possessing a certain degree of insu- 

 lating-power, and with a determinate distance between the 

 electrodes. This peculiar kind of propagation of electricity 

 is consequently to be observed with simpler apparatus than I 

 at first believed %. More experiments on this subject I hope 

 to communicate hereafter ; I will now only remark that a 

 fresh argument is therebv furnished against the existence of 

 a so-called metallic conduction in compound substances, since 

 extremely intense galvanic currents are transmitted through 

 badly conducting liquids in the same way as induced currents; 

 and we may regard this transmission as effected by rapid suc- 

 cessive self-discharges of a condenser, in which the liquid 

 layer between the electrodes plays the part of insulator, and 

 the electrodes form the coatings § . 



The Hague, March 1878. 



* E. Wiedemann, Pogg. Ann. vol. cliv. p. 319. 



t Lapschin and Tichanowitsch, loc. cit. 



X Lapschin and Tichanowitsch (op. cit.) state that in ether an undula- 

 tory motion was produced from the positive to the negative pole by the 

 current from only 900 Bunsen elements. 



§ Herwig (Pogg. Ann. vol. clix. p. 83) arrived at the same representa- 

 tion hy a quite different train of reasoning. I take this opportunity to 

 point out to chemists how desirable it is that they should investigate the 

 electrolytic properties of the new substances discovered by them, as gene- 

 rally these are only with difncultv accessible to phvsicists. 



* 2G2 



