LECTURE V.] HISTORY OF CHEMISTRY. 69 



believe I may almost assume that we would do similarly if we 

 were placed in the same position. Listen, and judge ! 



In 1789 Galvani 1 discovered that upon simultaneously 

 touching a muscle and a nerve of a frog, by means of two 

 different metals which were joined together by a conductor, the 

 frog was convulsed. Galvani's explanation of this fact was 

 controverted and replaced by another, in 1792, by Volta. 2 

 We find the question of the cause of the electrical current 

 discussed for a long period. Is the contact of the two metals 

 sufficient to generate electricity, or must they also be separated 

 by a decomposable fluid conductor ? The reader is, no doubt, 

 aware of the answer which we must now give to this question, 

 in accordance with our scientific principles, even although the 

 opposite view is perhaps not wholly refuted. 3 We cannot in 

 this place further occupy our attention with these theories, 

 which belong to physics and not to chemistry. 



Nicholson and Carlisle 4 observed in 1800, that upon 

 discharging the galvanic pile through water, the latter is de- 

 composed into its constituents, hydrogen and oxygen. Many 

 endeavours were made to observe similar phenomena in the 

 cases of other substances, but the first of the more important 

 investigations into the nature of the decomposition of chemical 

 compounds by means of the electric current, comes from 

 Berzelius and Hisinger, and was published in i8o3. 5 These 

 two investigators studied the action of dynamic electricity upon 

 salt solutions, and, further, upon ammonia, sulphuric acid, etc. 

 Their apparatus was so arranged that they were able to collect, 

 separately, the constituents liberated at the different poles. In 

 this way they arrived at the highly remarkable result, that 

 substances may be divided into two groups in respect to their 

 behaviour towards the galvanic current; that hydrogen, the 

 metals, the metallic oxides, the alkalies, the earths, etc., 



1 De Viribus Electricitatis in Motu Musculari Commentarius. Com 

 mentarii Acad. Bononiae. Vol. 7 (1791). 2 Giornale Fisico-medico di L. 

 Brugnatelli, 1794; Gren's Journal der Physik. [2], 2. 3 Compare Wiede- 

 mann, Galvanismus. I, 25. 4 Nicholson's Journal (quarto), 4 (1801), 183. 

 5 Ann. Chim. 51, 167. 



