Prof. Faraday on Electric Conduction. 101 



bodies we retain for consideration the class of electrolytes only, 

 then, though the amount of electricity of a given intensity which 

 these can transmit electrolytically when they are fluid is often 

 almost infinitely greater than that which they can convey on- 

 wards by conduction proper when they are solid, still the con- 

 duction in the latter cases is very evident. A piece of perfectly 

 dry solid nitre, and of many other electrolytes, discharges a gold- 

 leaf electrometer very freely, and I believe by the power of con- 

 duction proper ; and that being the case, I do not see that the 

 assumption of the very highest condition of electrolytic conduc- 

 tion when the nitre is rendered fluid is any argument for the 

 absolute disappearance of the conduction proper which belonged 

 to the body in the solid state, though it may override the latter 

 for the time, and make it insensible. These considerations are, 

 however, such as arise rather from the absence of the final and 

 strict proof on the opposite side, than from anything very posi- 

 tive in their own character ; but it has occurred to me that the 

 phaeuomena of static electricity will furnish us with many reasons 

 of a positive natui-e in favour of the possession by liquid electro- 

 lytes of the power of conduction proper. Some of these I will 

 endeavour briefly to state, illustrating the subject by a reference 

 to water, which in its pure state has but a low degree of electro- 

 lytic conduction. 



The ordinary phsenomena of static charge and induction are 

 well known. If an excited glass rod or other body be held near 

 a light gilt sphere, suspended from the hand by a metal thread, 

 the inductive action disturbs the disposition of the electricity in 

 the sphere, and the latter is strongly attracted ; if in place of 

 the sphere a soap bubble be employed, the same results occur. 

 If a dish filled with pure distilled water be connected with the 

 earth by a piece of moist bibulous paper, and a ball of excited 

 shell-lac be suspended 2 or 3 inches above the middle of the 

 water, and if a plate of dry insulating gutta-percha, about 8 inches 

 long and 2 inches wide, have its end interposed between the 

 water and the shell-lac, it may then be withdrawn and examined, 

 and will be found without charge, even though it may have 

 touched the shell-lac ; but if the end once touch the water under 

 the lac (and it may be dipped in) so as to bring away a film of 

 it, charged with the electricity the water has acquired by the 

 induction, it will be found to possess, as might be expected, a 

 state contrary to that of the inductric shell-lac. 



In order to exclude any conducting body but water from what 

 may be considered as a reference experiment, two calico globular 

 bags with close seams were prepared, and being wetted thoroughly 

 with distilled water, were then filled with air by means of a fine 

 blowpipe point ; they were then attached to two suspending 



