324 Dr. L. Bleekrode on Electrical Conductivity [Nov. 16, 



proposal, but I had also tlie favour of his highly esteemed aid in the 

 experiments we thus made together*. 



§ 2. Effects of the Current of a Battery of 8040 cells on strongly insulating 

 liquids. By Dr. L. Bleekrode, aided hy Waeren De La Eue, P.E.S. 



At the time of these experiments, the battery, which has been already 

 the subject of some communications to the E/oyal Society, had attained 

 a number of 8040 cells, which could be separately used in different series, 

 so as to obtain currents of various intensity ; the longest spark produced 

 between a point positive and a disk negative in free air had a length of 

 8-5 millims. (0*348 inch). "We tried only the liquids named above; though 

 few in number, yet they are interesting from their constitution and their 

 importance as chemical compounds. 



The following notes ware made as we experimented on the substances 

 ready for examination. 



I. Ammonia (Hg N). 



The current of 3240 cells confirmed the results obtained already on a 

 former occasion, when the ordinary galvanic battery of 80 cells was used, 

 only the effect was stronger now. Streams of a deep blue colour arose 

 in the liquid gas, and the positive electrode assumed a black colour, much 

 gas being evolved at the same time. "When the current ceases, the blue 

 colour rapidly disappears, and the liquid becomes bright again. 



II. Bisulphide of Carbon (CS^). 

 "We first tried the current from 3240 cells ; the negative electrode, 

 some inches in length, was seen to be repelled from the surface of the liquid 

 till it came in contact with the glass of the tube ; and it appeared from 

 some floating particles that internal motions took place, probably caused by 

 heat, though the hand did not detect any elevation of temperature. The 

 current from 5640 cells was too strong ; then the spark jumped between 

 the electrodes, and these were covered with a brown tint (from a deposit of 

 carbon). "We tried afterwards if a polarization current could be detected 

 on a Thomson galvanometer; but this failed, yet the instrument was very 

 sensible. If two fingers were placed on the ends of the connectiug 

 wires, the current which was excited by this contact was strong enough 

 to cause the luminous index to fly away off the whole scale. 



III. Benzine (CgHJ. 

 "With 3240 cells a strong vibratory motion was observed in the liquid. 

 "With 5640 cells this motion increased and became more apparent, also 

 a ringing sound (very similar to that emitted by the contact-breaker of a 



* I owe also many thanks to Prof. Prankland, who granted me all the facilities of 

 his chemical laboratory in the Science Schools, South Kensington, and to his assistant, 

 Mr. Cameron, for his valuable aid in preparing these substances. 



