68 Biographical Notice of Alexander Volta. 



and to the invention of new ones ; the Electroscopes of 

 Cavallo, and of De Saussure, obtained in his hands, the 

 greatest exactness :, the Electrophorus, and the condenser, 

 owed their origin to him. This last apparatus, especially, 

 founded on the true principles of electricity, of which it is 

 the consequence, is to that science, what the microscope is 

 to natural history, in permitting us to appreciate the quanti- 

 ties of electricity, which by their feeble effects, would have 

 entirely escaped the means formerly known. 



The condenser was to shew, at a later period the impor- 

 tant part, which the electric agent held in nature and the great 

 number of phenomena which produce it, and finally it was 

 to become, to Volta himself, the basis of his grand discov- 

 ery, the means of shewing that there is a development of 

 electricity on the contact of two metals. 



It was in electricity that Volta found an explanation of 

 the greater number of meteorological phenomena. 



His hypothesis of the formation of hail, is ingenious, and his 

 observations upon the periodical return of clouds, are not 

 without interest; but in general, we must distinguish through- 

 out this subject, the theories of the author, from the numer- 

 ous, and curious facts, with which he has enriched the sci- 

 ence of meteorology, still so imperfect. 



Let us turn our attention, for a moment to the labours of 

 Volta, relative to chemistry ; labours, which are worthy of 

 our attention, from their results, and from the progress of 

 invention which distinguished them. It was he who discov- 

 ered the inflammable gas of marshes, and who furnished an 

 explanation, the consequence of the former, of the wander- 

 ing fires, and of those igneous phenomena, which are some- 

 times produced upon the surface of the ground. He has 

 shewn that they result from the combustion of this gas, by 

 means of electricity. 



It was on the occasion of the discovery of an inflammable 

 spring, which was observed to issue from a fountain in 1776, 

 that he suspected the true cause of this phenomenon and 

 of some other similar ones and which he attributed, not to 

 a circumstance purely local, but to the formation of a gas 

 by the fermentation of vegetable and animal substances in 

 contact with water. 



Thus he shewed that wherever there was muddy ground 

 or stagnant water, on stirring the bottom, bubbles of this 

 gas would arise; which gas was proto-carburetted hydrogen. 



