EPOCH OF DAVY AND FARADAY. 293 



the responsibility which the narration involves and I have endeavor- 

 ed earnestly, and I hope not in vain, to speak as if I were removed 

 by centuries from the personages of my story. 



The phenomena observed in the Voltaic apparatus were naturally 

 the subject of many speculations as to their cause, and thus gave rise 

 to " Theories of the Pile." Among these phenomena there was one 

 class which led to most important results : it was discovered by Nichol 

 son and Carlisle, in 1800, that water was decomposed by the pile ot 

 Volta ; that is, it was found that when the wires of the pile were 

 placed with their ends near each other in the fluid, a stream of bub- 

 bles of air arose from each wire, and these airs were found on exami- 

 nation to be oxygen and hydrogen ; which, as we have had to narrate, 

 had already been found to be the constituents of water. This was, as 

 Davy says, 1 the true origin of all that has been done in electro-chemi- 

 cal science. It was found that other substances also suffered a like 

 decomposition under the same circumstances. Certain metallic solu- 

 tions were decomposed, and an alkali was separated on the negative 

 plates of the apparatus. Cruickshank, in pursuing these experiments, 

 added to them many important new results ; such as the decomposi- 

 tion of muriates of magnesia, soda, and ammonia by the pile ; and the 

 general observation that the alkaline matter always appeared at the 

 negative, and the acid at the positive, pole.. 



Such was the state of the subject when one who was destined to do 

 so much for its advance, first contributed his labors to it. Humphry 

 Davy was a young man who had been apprenticed to a surgeon at 

 Penzance, and having shown an ardent love and a strong aptitude for 

 chemical research, was, in 1798, made the superintendent of a "Pneu- 

 matic Institution," established at Bristol by Dr. Bedcloes, for the pur- 

 pose of discovering medical powers of factitious airs. 2 But his main 

 attention was soon drawn to galvanism ; and when, in consequence of 

 the reputation he had acquired, he was, in 1801, appointed lecturer at 

 the Royal Institution in London (then recently established), he wa? 

 soon put in possession of a galvanic apparatus of great power ; and 

 with this he was not long in obtaining the most striking results. 



His first paper on the subject 3 is sent from Bristol, in September 

 1800 ; and describes experiments, in which he had found that the de- 

 compositions observed by Nicholson and Carlisle go on, although the 



1 Phil. Trans. 1826, p. 386. " Paris, Life of Davy, i. 58. 



'Nicholson's Journal, 4 to. iv. 275. 



