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Dr. G. Gore. 



varies with, the nature of the liquids and with other circumstances not 

 yet determined. The electric current, by liberating electrolytic pro- 

 ducts at the two surfaces of each meniscus, must also further affect 

 ordinary diffusion and electric osmose at the meniscus. 



11. Influence of Miscibility of the Liquids. 

 It would be interesting to examine the influence of non-miscible 

 electrolytes upon each other under the usual conditions in the single 

 meniscus apparatus, if a pair of suitable ones could be found. I 

 attempted to pass a current from a single series of twenty-five 

 Grove's cells through two immiscible liquids lying in contact with 

 each other in a U glass tube 10 millims. diameter. One liquid con- 

 sisted of water saturated with ether and mercuric chloride, and the 

 other of ether saturated with water and that salt. No perceptible 

 current passed, or other visible effect was produced. 



12. Influence of Light, Heat, and Temperature. 



I have not observed that the phenomena are in any way related to 

 the influence of luminous rays ; nevertheless, as light is well known 

 to affect chemical union, it is not unreasonable to suppose that it in- 

 fluences (though in a very much less degree) mechanical mixture. 



The influence of temperature of the liquids upon the phenomena 

 has not been experimentally examined, partly because no valuable 

 addition of knowledge was likely to accrue, and partly because rise of 

 temperature is a disturbing condition in the case, and it would be 

 difficult to manipulate with heated liquids, The effects of heat of 

 conduction resistance interfere in nearly every instance with the 

 detection and accurate observation of the other phenomena, especially 

 in cases where a powerful current circulates. By the influence of 

 such heat, the lower liquid expands, and thus appears to increase in 

 volume by diffusion. When the temperature is higher, wavy lines 

 are produced at the meniscuses, especially at the positive one, and 

 as the heat increases, streams of upflow of the lower solution or of 

 downflow of the upper one occur ; and finally, bubbles of steam 

 or gas are produced at the positive meniscus, and stop the experiment. 

 The heat evolved appears to be mostly at the contiguous liquid surfaces, 

 probably because acids and bases are transferred there by the current 

 and chemically unite ; it is greatest at the positive meniscus, because 

 the relative densities of the acid and basic layers there tend to 

 localise the effect. 



13. Influence of Electric Conditions. 

 With the exception of ordinary liquid diffusion, adhesion, and 

 capillary action, all the effects are primarily due to the electric current, 

 and therefore dependent upon conduction and magnitude of flow. The 

 chief locality of action is at and near the meniscuses, apparently also to 



