336 IDENTITY OF THE ELECTRICITIES. SECT. XXXV. 



its composition, by means of magnetic, action ; and M. 

 Botto of Turin has shownHhe chemical effects of the 

 thftfirua-pJer'.t-.rrcjty in the decomposition of water, and 

 some other substances. The* elecjj^e and ggkMwic 

 shock, the flash in the eyes, and~thesensation on the 

 tongue, are well known. All these effects are produced 

 by magneto-electricity, even to a painful degree. The 

 torpetfcTand gyifmOTTTT^lectricus give severe shocks, and 

 the limbs of a frog have been convulsed by thermo-elec- 

 tricity. The last point of comparison is the spark, 

 which is common to the ordinary Voltaic and magnetic 

 fluids ; and Professor Linari, of Siena, has very lately 

 obtained both the direct and induced sparks from the 

 torpedo, proving that in this respect aniraal_eltricity 

 does not differ from the others. Indeed, the conclusion 

 drawn by Dr. Faraday is that the five kinds of electri- 

 city are identical, and that the differences of intensity 

 and quantity are quite sufficient to account for what 

 were supposed to be their distinctive qualities. He has 

 given still greater assurance of their identity by showing 

 that the magnetic force and the chemical action of elec- 

 tricity are in direct proportion to the absolute quantity 

 of the fluid which passes through the galvanometer, 

 whatever its intensity may be. 



In light, heat, and electricity, or magnetism, nature 

 has exhibited principles which do not occasion any ap- 

 preciable change in the weight of bodies, although their 

 presence is manifested by the most remarkable mechan- 

 ical and chemical action. These agencies are so con- 

 nected, that there is reason to believe they will ulti- 

 mately be referred to some one power of a higher order, 

 in conformity with the general economy of the system 

 of the world, where the most varied and complicated 

 effects are produced by a small number of universal 

 laws. These principles penetrate matter in all direc- 

 tions ; their velocity is prodigious, and their intensity 

 varies inversely as the squares of the distances. The 

 development of electric currents, as well by magnetic 

 as electric induction, the similarity in their mode of ac- 

 tion in a great variety of circumstances, but above all, 

 the production of the spark from a magnet, the ignition 

 of metallic wires, and chemical decomposition, show that 



