72 Biographical Notice of Alexander Volta, 



of the faculty which the apparatus possesses, of producing 

 the electrical agent as fast as it is expended. 



It may seem to be a departure from the subject of this 

 article to describe these phenomena, but we think with the 

 Italian author, that to become duly sensible of the value of 

 the great discovery of Voita, it will be necessary to present 

 some of the consequences which flow from it, and to show 

 how fruitful in important results it has been in the hands of 

 philosophers. It is not an exposition, nor even a complete 

 enumeration of the effects of the pile that we pretend here 

 to make; it is only some of the more conspicuous facts which 

 owe their origin to this apparatus, which we wish to dwell 

 upon. 



In following the author of the biographical notice, we 

 shall recall the curious experiments of Erman, on the prop- 

 erty which certain bodies possess, of conducting only one or 

 the other of the electricities of the pile, and the distinction 

 which it draws between unipolar and bipolar conductors ; 

 the different forms given to the voltaic apparatus by Volta 

 himself, by Woliaston,* Pepys, Children, Accum, &,c. ; the 

 dry piles made by De Luc and Zamboni; the wet piles con- 

 structed by Davy with other substances be&ides metals, &c. 

 All these details belong more properly to the theory than to 

 the effects of the pile ; as we shall partly complete them by 

 citing with the author, the labors of Marianini relative to the 

 electromotive faculty of certain substances, and to the influ- 

 ence of temperature and other circumstances, either upon 

 this faculty or upon conductibility ; and lastly in adverting 

 to the researches of Prof A. De La Jlive upon the electric 

 currents disseminated in fluids, and the experiments in which 

 he has laid hold of several remarkable analogies between 

 electricity in this state, and the properties of light and of 

 radiant caloric. 



The services which the discovery of the pile has rendered 

 to philosophy, are neither less important, nor less rich in con- 

 sequences than those which it has rendered to chemistry. 

 Not only has voltaic electricity furnished a new and much 

 more powerful mode of producing heat and light, than the 

 ancient, but it has given birth to a new class of phenomena, 

 of a kind, then quite unknown to science. 



Philosophers remarked not long after Volta had put the 

 pile into their hands, that conductors placed between the 



* Dr. Hare is certainly entitled to be raentioned in this list. — Ed. 



