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The Bakerian Lecture: on some new Electro-chemical Phenomena. 

 By William Thomas Brande, Esq. F.R.S. Prof. C/iem. R. I. 

 Read November 25, 1813. [Phil. Trans. 1814, p. 51.] 



When any decompositions are effected by means of the voltaic 

 battery, it is known that one of the constituents is attracted towards 

 the positive pole, and the other to the negative. Of the ultimate 

 chemical elements a very small proportion is attracted by the former, 

 by far the greatest part being attracted by the negative pole ; and it 

 is thence inferred that these are themselves possessed of inherent 

 positive electricity. 



Although all the differences observable between voltaic and com- 

 mon electricity have already been shown to depend solely upon 

 difference of quantity and of intensity, Mr. Brande has thought it 

 would be desirable to trace their relation, with regard to a series of 

 phenomena that have not yet undergone a comparative examination. 



When the flame of a candle is interposed between two bodies 

 oppositely electrified, Mr. Cuthbertson observed that heat passes to 

 the negative surface, and thence inferred the passage of the electric 

 fluid in the same direction. It occurred to Mr. Brande, that possibly 

 this effect might depend on the nature of the substance employed 

 as the combustible body; and by substituting the flame of phosphorus 

 instead of the candle, he found the effects were reversed : for then 

 the positive surface became considerably warmer than the negative, 

 the flame itself being now visibly attracted towards the positive ball, 

 instead of inclining like the flame of the candle toward the negative. 



The rapid formation of acid matter during the combustion of 

 phosphorus, appeared sufficient to occasion the attraction of this 

 flame to the positive side, in conformity to what occurs in voltaic 

 experiments ; and Mr. Brande conceives the carbon and hydrogen 

 which abound in the flame of the candle to be the cause why that 

 flame takes the opposite direction. 



When the flame of olefiant gas was substituted, the negative ball 

 was 10 warmer than the positive ; the flame of sulphuretted hydrogen 

 gave only 3 excess to the negative ball ; that of phosphuretted 

 hydrogen communicated 2 to the positive ball. Arseniuretted 

 hydrogen heated the negative ball most, though the fumes of white 

 arsenic were visibly drawn toward the positive ball. With flames of 

 hydrogen or of carbonic oxide the difference of temperature was too 

 small to be fully depended on, but the flame of the latter was directed 

 towards the positive ball. With respect to sulphur, no particular 

 direction was observed to be given to the flame, but the vapour 

 passed toward the positive ball. When potassium in a state of 

 combustion was placed between the electrified balls, both the flame 

 and the fumes were drawn to the negative conductor. The attrac- 

 tion of other fumes being tried, not in the state of combustion, 

 ammonia afforded no distinct result. Muriatic gas was visibly 

 attracted by the positive pole ; and nitrous acid gas was also drawn 

 in the same direction. The fumes that arise from benzoin and from. 



