Additional Notes. 441 



tesearches of Faeroni, Dr. Ash, and Creve, exhibiting 

 the peculiar action of metals in contact with each other upon 

 water, demonstrated the production of the Galvanic influ- 

 ence in combinations wholly composed of inorganic matter, 

 and thereby connected it with the general principles of phy- 

 sics. The third epocha in the history of Galvanism is found- 

 ed on the discovery of the m.eans of accumulating this in- 

 fluence by the batterij or pile of Volt a, wiiich paved the 

 way for a distinct exhibition of the analogy between Gal- 

 vanism and common Electricity, ^rhe Jourt/i arises from the 

 discovery of the clionical agencies of Galvanism. In the 

 prosecution of this last train of inquiry, the principal degree 

 of praise is due to the British experimenters, and, among 

 these, chiefly to Messrs. Carlisle, Nicholson, Cruick- 

 SHANK, Haldane, Henry, and more particularly to Mr. 

 Davy and Dr. VVollaston. 



Messrs. Carlisle and Nicholson did much towards 

 establishing the electricity of the pile, by ascertaining that it 

 is minus in the silver end, and phis in the zinc end. They 

 also demonstrated its chemical action, especially in the de- 

 composition of water; a most interesting experiment, which 

 has led to many very important results. 



Mr. Cruickshank was the first discoverer of the Gal- 

 vanic production of alkali. In his experiments he supposed 

 ammoniac to be generated; while, according to those of 

 some others, the alkali produced was thought to be fixed. 

 He likewise invented the mode of placing the metals hori-. 

 zontally in a kind of trough, which, in several respects, is 

 much more convenient than the apparatus of Volta. And 

 he was the first who succeeded in charging the Leyden phial 

 by means of the Galvanic pile. 



Mr. William Henry ascertained, by his experiments, 

 that the sulphuric and nitric acids may be decomposed by the 

 operation of the Galvanic influence; but, in his attempts on 

 the m.uriatic acid, he only succeeded in decomposing the wa- 

 ter adhering to it. He also demonstrated that ammoniac may 

 be decomposed in a similar manner. 



Col. Haldane found that the effects of the apparatus of 

 Volta were suspended when it was immersed in water; 

 and that this likewise was the case when it was confined in 

 azotic gas, or placed under the vacuum of an air-pump. He 

 observed that tp.e pile acted more powerfully when immersed 

 in a given quantity of oxygen gas than in the sanre bulk of 

 atmospherical air. 



