262 Dr. Faraday's Experimental Researches in Electricity. 



as affording only secondary results relative to the acetic acid 

 (749.). With many of the metallic acetates the results at 

 both electrodes are secondary (746. 750.). 



Acetate of soda fused and anhydrous is directly decomposed, 

 being, as I believe, a true electrolyte, and evolving soda and 

 acetic acid at the cathode and anode. These, however, have no 

 sensible duration, but are immediately resolved into other sub- 

 stances ; charcoal, sodiuretted hydrogen, &c, being set free 

 at the former, and as far as I could judge under the circum- 

 stances, acetic acid mingled with carbonic oxide, carbonic 

 acid, &c, at the latter. 



775. Tartaric Acid. — Pure solution of tartaric acid is almost 

 as bad a conductor as pure water. On adding sulphuric acid 

 to it, it conducted well, the results at the positive electrode 

 being primary or secondary in different proportions, according 

 to variations in the strength of the acid and the power of the 

 electric current (752.). Alkaline tartrates gave a large pro- 

 portion of secondary results at the positive electrode. The 

 hydrogen at the negative electrode remained constant unless 

 certain metallic salts were used. 



776. Solutions of salts containing other vegetable acids, as 

 the benzoates ; of sugar, gum, &c, dissolved in dilute sul- 

 phuric acid; of resin, albumen, &c, dissolved in alkalies, were 

 in turn submitted to the electrolytic power of the voltaic cur- 

 rent. In all these cases, secondary results to a greater or 

 smaller extent were produced at the positive electrode. 



777. In concluding this division of these Researches, it can- 

 not but occur to the mind that the final result of the action 

 of the electric current upon substances placed between the 

 electrodes, instead of being simple may be very complicated. 

 There are two modes by which these substances may be de- 

 composed, either by the direct force of the electric current, or 

 by the action of bodies which that current may evolve. There 

 are also two modes by which new compounds may be formed, 

 i. e. by combination of the evolving substances whilst in their 

 nascent state (658.), directly with the matter of the electrode; 

 or else their combination with those bodies, which being con- 

 tained in, or associated with, the decomposing conductor, are 

 necessarily present at the anode and cathode. The complexity 

 is rendered still greater by the circumstance that two or more 

 of these actions may occur simultaneously, and also in variable 

 proportions to each other. But it may in a great measure 

 be resolved by attention to the principles already laid down 



(747.). 



778. When aqueous solutions of bodies are used, secondary 

 results are exceedingly frequent. Even when the water is not 



