438 Dr. Faraday's Experimental Researches in Electricity, 



simultaneous decomposition of water and salts, &c., which 

 still require investigation. But whatever the results on these 

 and numerous other points may be, I do not believe that the 

 facts which I have advanced, or even the general laws de- 

 duced from them, will suffer any serious change ; and they 

 are of sufficient importance to justify their publication, even 

 though much may remain imperfect or undone. Indeed, it is 

 the great beauty of our science, chemistry, that advancement 

 in it, whether in a degree great or small, instead of exhausting 

 the subjects of research, opens the doors to further and more 

 abundant knowledge, overflowing with beauty and utility, to 

 those who will be at the easy personal pains of undertaking 

 its experimental investigation. 



872. The definite production of electricity (868.) in asso- 

 ciation with its definite action proves, I think, that the current 

 of electricity in the voltaic pile is sustained by chemical de- 

 composition, or rather by chemical action, and not by contact 

 only. But here, as elsewhere (857.)> I beg to reserve my 

 opinion as to the real action of contact, not having yet been 

 able to make up my mind as to its being either an exciting 

 cause of the current, or merely necessary to allow of the con- 

 duction of electricity, otherwise generated, from one metal to 

 the other. 



873. But admitting that chemical action is the source of 

 electricity, what an infinitely small fraction of that which is 

 active do we obtain and employ in our voltaic batteries ! Zinc 

 and platina wires, one eighteenth of an inch in diameter and 

 about half an inch long, dipped into dilute sulphuric acid, so 

 weak that it is not sensibly sour to the tongue, or scarcely to 

 our most delicate test papers, will evolve more electricity in 

 one twentieth of a minute (860.) than any man would willingly 

 allow to pass through his body at once. The chemical action 

 of a grain of water upon four grains of zinc can evolve electri- 

 city equal in quantity to that of a powerful thunder-storm 

 (868. 861.). Nor is it merely true that the quantity is active; 

 it can be directed and made to perform its full equivalent 

 duty (867. &c). Is there noi, then, great reason to hope and 

 believe that, by a closer experimental investigation of the prin- 

 ciples which govern the development and action of this subtile 

 agent, we shall be able to increase the power of our batteries, 

 or invent new instruments which shall a thousandfold surpass 

 in energy those which we at present possess ? 



874?. Here for a while I must leave the consideration of the 

 definite chemical action of electricity. But before I dismiss 

 this series of experimental researches, I would call to mind 

 that, in a former series, I showed that the current of electricity 



