10 On some Chemical Agencies of Electr'tcily. 



Tlie water soon gained ihe property of affecting the tint 

 of turmeric; and fixod alkali and lime were both obtained 

 from it: and this eflect took place in repeated experiments: 

 the fixed alkali, however, diminished in qiianlity every time; 

 and after eleven pr-iccsses, conducted from two to three 

 hours each, disappeared altogether. The produclion of lime 

 water was nniform. 



I made a solution of .500 grains of this marble in nitric 

 acitl ; T decomposed the mixture bv carbonate of ammonia, 

 and \ collected and evaporated the fluid part, and decom- 

 posed the nitrate of annnonia bv heat. About 3-4ths of a 

 grain of fixed saline matter remained, which had soda for 

 its base. 



It was possible that the Carrara marble might have been 

 recently exposed to sea water; I therefore tried, in th.e same 

 wav, a piece of granular marble, which I had myself broken 

 from a rock on one of the highest of the ])rimilive moun- 

 tains of Donegal. > It afforded fixed alkali by the agency of 

 negative electricity. 



A piece of argillaceous schist from Cornwall, treated in 

 the same manner, o-ave the same result ; and serpentine from 

 the Lizard, and granwacke from North Wales, both af- 

 forded soda. It i^ probable that there are few stones that 

 do not contain some minute poitions of saline matter, which 

 in many cases may be mechanically dilTused through their 

 substance; and it is not difficult to conceive the possibility 

 of this, when we consider tb.at all our common rocks and 

 strata hear evident marks of having been antiently covered 

 bv the sea. 



I was now al le to determine distinctly that the soda pro- 

 cured in glass tubes came principally from the glass, as I 

 had always supposed. 



[ used the two cones of gold with the purified water and 

 the amianthus; the process was conducted as usual. After 

 a quarter of an hour, the negatively electrified tube did not 

 change the colour of turmeric. I introduced into the top of 

 it a bit oF glass ; in a few minutes the fluid at the surface 

 rendered the tint of the paper of a deep bright brown. 



I had never made any experiments in which acid matter 



having 



