466 Recent Improvements in Science. 



Article IX. 

 Notice of some Recent Improvements in Science. 



ELECTRICITY. 



Electricity by contact. — According to Karsten, the metals, 

 and, perhaps, all solid bodies, become positive in fluids ; 

 and the fluid in which they are plunged becomes negative. 



2. A solid, which is half immersed in the fluid, acquires 

 an electric polarity ; the submersed portion possesses posi- 

 tive electricity, and that which is not immersed, negative 

 electricity. 



3. Solid bodies present a great difference in their elec- 

 tro-motive force, in relation to the same fluid, and this 

 difference is the true cause of the electrical, chemical and 

 magnetic activity of the circuit. 



4. If two solid electromotors, but of different electro- 

 motive force, are immersed in the same fluid without 

 touching, the most feeble electromotor receives the oppo- 

 site electricity to that of tbe strongest electromotor, and 

 becomes, of consequence, negatively electric. 



5. The half of the weakest electromoter, which rises 

 above the fluid, exhibits the opposite electricity to that of 

 the immersed portion, and becomes, consequently, positively 

 electrical. 



6. The electro-motive electricity of a fluid depends on 

 the property of being reduced by two solid electromotors, 

 of different force, to such a state that the two electromo- 

 tors receive opposite electricities. In general, all fluids 

 which are bad conductors of electricity, posses^ the pro- 

 perty which has been pointed out ; but not fluids which are 

 not conductors, nor those which are good conductors. 

 However, the intensity of the electro-motive force of fluids, 

 does not depend only on the more or less imperfect con- 

 ductibility, but on other relations which are not sufficiently 

 known. 



7. The electro-motive effects of two metals, which form 

 a circuit in the same fluid, are founded upon the continual 

 excitation and neutralization of the opposite electricities 

 which take place in the fluid. They are produced by the 



