concerned in the P/ianomena of ordinary Electricity, 8jg. 293 



electricity, and to dissever it from its alleged identity with vol- 

 taic electricity. When we find two estimates of an effect to agree 

 pretty well, while a third is forty-two times greater than one, 

 and thirty-eight times greater than the other, it is plain there 

 is a monstrous error somewhere ; and hence, before we can ven- 

 ture to draw any conclusion, it will be proper to investigate the 

 grounds on which the discordant opinion has been formed. This 

 becomes the more necessary, when it is recollected that the 

 stronghold of those who maintain the identity of the voltaic and 

 electric agents is the almost unlimited supply of the latter at a 

 low intensity, which they affirm can be brought into action du- 

 ring the exhibition of any phenomenon caused by the former. 



Faraday has estimated, as has been already observed, that one 

 grain of water decomposed by four grains of zinc can evolve 

 electricity equal in quantity to that of a powerful thunder-storm, 

 to a flash of lightning, and to 800,000 charges of a Leyden bat- 

 tery, consisting of 24£ square feet of coated surface, charged 

 each time with thirty turns of a powerful plate electrical machine, 

 each turn of the plate giving ten or twelve sparks of one inch in 

 length. 



This is no trivial quantity ; and it ought to be easy to obtain 

 powerful if not fearful manifestations of its presence. In order 

 to set this matter in a clear point of view, I made a few experi- 

 ments, the result of which it was easy to foresee ; and they were 

 made as illustrations of the nature of my objections to the doc- 

 trine impugned, as topics to reason on, as facts to found calcu- 

 lations upon, rather than as instruments of research. 



Having prepared a piece of very thin zinc-foil weighing four 

 grains, and in surface measuring five-eighths of an inch by one 

 inch, and also a plate of platinum five times the surface of the 

 zinc, I connected each with one of the gold leaves of an electro- 

 meter, the detached gold leaves of which were separately insu- 

 lated, and were moveable towards or from each other by means 

 of glass handles. The gold leaves were then moved towards each 

 other, until they and the brass arms from which they hung were 

 in good contact. An insulated vessel containing sulphuric acid, 

 at that moment diluted with double its bulk of water, was pre- 

 pared ; and while the mixture was still very hot, the zinc and 

 platinum plates were immersed. The platinum gave off hydrogen, 

 and the zinc was dissolved in 1| minute. While the solution 

 of the zinc was in progress, the gold leaves were gently sepa- 

 rated by their glass handles, and approached again until they 

 touched: there was not the slightest appearance of attraction or 

 repulsion ulicii tin v were separated or approached. According to 

 Faraday's estimate, electricity equal to no less than 210 millions 

 of one-inch sparks passed through the gold leaves in 1 }, minute 



