444 Notice of some Recent 



Article VI. 

 Notice of some Recent Improvements in Science. 



ELECTRICITY. 



Electricity hy Contact.— M, Karsten, in a letter of 150 

 pages addressed to Humboldt, has discussed this subject. 

 The paper has excited much attention in Germany, but it 

 contains few new facts, and many speculations. -His conclu- 

 sions are, 1st. The metals, and perhaps, all solid bodies 

 become positive when plunged into a liquid ; the latter 

 becomes negative. 2nd. When the body is not wholly im- 

 mersed, its two ends take opposite electrical states. 3rd. 

 Solid bodies differ much in regard to their electro-motive 

 force with the same liquid, and it is in this difference that 

 the electrical activity both chemical and magnetic of the 

 pile depends. 4th. When two electromotors of different 

 forces are plunged into the same liquid without being in 

 contact, the feeblest takes the opposite electricity to that 

 of the strongest, and becomes consequently negative. 5th 

 The feeblest part of the solid electromotor, placed out of 

 the liquid, possesses equally the opposite electricity to that 

 of the part immersed. 6th. The electromotive energy of 

 a liquid depends on its power of acquiring by the presence 

 of two dissimilar solid electromotors, a state, by virtue of 

 which, it yields more or less readily electricities opposite 

 to the same electromotors. All bad conducting liquids 

 possess in general this property, but it belongs neither to 

 perfectly isolating liquids, (such as oils, &;c.,) nor to very 

 good conducting liquids, (such as mercury and liquid 

 metals.) The electro-motive energy of a liquid, does not, 

 however, depend only on its conducting power, but also 

 apparently on several other conditions not yet properly 

 known. 7th. The electro-motive effects of two metals 

 forming with a liquid, a closed circuit, result from the dis- 

 engagement and re-combination of opjoosite electricities in 

 the liquid. These effects are excited by the electro-motive 

 relation of the two unequal electromotors to the liquid ; 

 they are favoured by the electro-motive relation of the 

 strongest electromotor to the weakest, and are accelerated 

 by the immediate contact of the two electromotors, accord- 



