ON' SOME CHEMICAL AGEI^CIES Ot EtECTRIClTYk 335 



,' When compatible mixtures of neiitrosaline solutions cotl* Action of elec- 

 faining the common mineral acids were used, the different tncity in de- 

 acids and the different bases seemed to separate together in pounds. 

 a mixed state, without any respect to the orders of af- 

 finity. 



When metallic solutions were employed, metallic cry- 

 stals or depositions were formed, as in common galvanic 

 experiments, on the negative wire, and oxide was likewise 

 deposited round it; and a great excess of acid was soon 

 found in the opposite cup. With solutions of iron, zinc, 

 and tin, this effect took place, as well as with the more 

 oxidable metals: when muriate of iron was used, the black 

 substance deposited upon the wire was magnetic, and dis- 

 solved with effervescence in muriatic acid ; and when sul- 

 phate of zinc was used, a gray powder possessed of the 

 metallic lustre, and likewise soluble with effervescence, 

 appeared; and in all cases acid in excess was exhibited on 

 the positive side. 



Strong or saturated saline solutions, as might have been 

 expected, afforded indications of the progress of decompo- ^ 



sition much more rapidly than weak ones ; but the smallest , 



proportion of neutrosaline matter seemed to be acted on 

 with energy. 



A very simple experiment demonstrates this last principle. 

 If a piece of paper tinged with turmeric is plunged into 

 pure water in a proper circuit, in contact with the negative 

 point, the very minute quantity of saline compound con- 

 tained in the paper affords alkaline matter sufficient to give 

 it instantly a brown tint near its point of contact : and acid 

 in the same manner is immediately developed from litmus 

 paper, at the positive surface. 



I made several experiments, with the view of ascertain- 

 ing whether, in the decompositions by electricity, the se- 

 paration of the constituent parts was complete from the 

 last portions of the compound; and whenever the results 

 were distinct, this evidently appeared to be the case. 



I shall describe one of the most conclusive of the experi- 

 tnents: a very weak solution of sulphate of potash, con- 

 taining 20 parts water and one part saturated solution, al 

 64"', was electrified in tlie two agate cups by the power x>f 



50 paii't 



