4 On the Decomposition ancLComposition 



those which demonstrate. the decomposition and composition 

 of the fixed alkalis, and the production of the new and ex- 

 traordinary bodies which constitute their bases. 



In speaking of novel methods of investigation, I shall not 

 fear to be minute. When the common means of chemical 

 research have been employed, I shall mention only results. 

 A historical detail of the progress of the investigation, of all 

 the difficulties that occurred, and of the manner in which 

 they were overcome, and of all the manipulations employed, 

 would far exceed the Ifmits assigned to this lecture. It is 

 proper to state, however, that when general facts are men- 

 tioned, they are such only as have been deduced from pro- 

 cesses carefully performed and often repeated. 



II. On tlie Methods used for the Decomposition of the fixed 

 Alkatis. 



The researches I had made on the decomposition of acids, 

 and of alkaline and earthy neutral compounds, proved that 

 the powers of electrical decomposition were proportional to 

 the strength of the opposite electricities in the circuit, and 

 to the conducting power and degree of concentration of the 

 materials employed. 



In the first attempts that I made on the decomposition 

 of the fixed alkalis, I acted upon aqueous solutions of pot- 

 ash and soda, saturated at common temperatures, by the 

 highest electrical power I could command, and which was 

 produced by a combination, of Voltaic batteries belonging to 

 the Royal Institution, containing 24 plates of copper and 

 zinc of \2 inches square, 100 plates of six inches, and 150 

 of four inches square, charged with solutions of alum and 

 nitrous acid ; but in these cases, though there was a high 

 intensity of action, the wafer of ihe solutions alone was 

 affected, and hydrogen and oxygen' disengaged with thq 

 production of much heat and violent effervescence. 



The presence of water appearing thus to prevent any de- 

 composition, I used potash in igneous fusion. By means of 

 a stream of oxygen gas from a gasometer applied to the 

 flame of a spirit lamp, which was thrown on a platina spoon 

 containing potash, this alkaii was kept for some minutes in 



a strong 



