into the Cause of Voltaic Electricity, 



Exp. III. 

 Number of Cent. Deg. of Time for the evolution of 



diaphragms. the helix. the same volume of gas. 



38° 5" 



1 3 25" 



2 no effect. 



From the first two experiments it may be seen in what an 

 enormous proportion the calorific intensity diminishes, ac- 

 cording to the increase in the number of diaphragms. In the 

 third experiment the current was made to pass at the same 

 time through the metallic helix, and an acid solution placed 

 in succession in its path. From this experiment it may be 

 seen that the interposition of a diaphragm which reduced to 

 T * 7 the calorific intensity of the current, only reduced its 

 chemical power to 3-; a difference which shows the consi- 

 derable influence which the rapidity of the current exerts 

 over calorific power; as I have shown in a special memoir. 

 (Bibl. Univer. Jan. 1829.) 



Summary. — We shall briefly recapitulate the results of these 

 researches. 



1. The contact of two heterogeneous bodies without calo- 

 rific, mechanical, or chemical action, is not of itself a source of 

 electricity. 



2. Chemical action, even the most feeble, develops a sen- 

 sible quantity of electricity ; but if this electricity be not 

 always perceptible, if especially its intensity be not always in 

 the ratio of the vivacity of the chemical action which pro- 

 duces it, it is essentially due to the immediate recomposition 

 of the two electricities which takes place upon the surface 

 attacked. 



3. Entering upon the theory of the pile, the production, 

 and distribution of electricity in this apparatus, may be com- 

 pletely explained by the development of electricity resulting 

 from the chemical actions, and the neutralizations of the free 

 electricities which take place from pair to pair. 



4. Attention being paid to the conductibility of the pile it- 

 self, and comparing it with that of the bodies placed between 

 its poles, all the dynamic effects of voltaic electricity, the cir- 

 cumstances which may modify the intensity of these effects, 

 and the apparent anomalies which they present may be easily 

 explained ; provided at the same time the principles above 

 stated are not lost sight of. 



Ryde,Isle of Wight, 10th Aug., 1837. 

 [We shall notice in our next Number M. De la Rive's paper On the in- 

 fluence of heat on the passage of an electric current from a liquid into a 

 metal, and also his Researches on the Properties of Magneto-electric Cur- 

 rents. — Edit.] 



2 Q 2 



