

ON SOME CHEMICAL AGENCIES OP ELECTRICITY. 45 



tin, and from the tin to the solution of potash; but in an General prin-. 

 arrangement composed of weak nitric acid, water, and tin; ehemical 



the order was from the acid to the tin, and from the tin to changes pro? 

 A , ■. ducod by elep* 



the water. ... tricky. 



These principles seem to bear an immediate relation to 

 the general phaeuoineua of decomposition and transference, 

 which have been the subject of the preceding details. 



in the simplest case of electrical action, the alkali which 

 receives electricity from the metal would necessarily, on be- 

 ing separated from it, appear positive; whilst the acid under 

 similar circumstances would be negative; and these bodies 

 having respectively, with, regard to the metals, that which 

 may be called a positive and a negative electrical energy, in 

 their repellent and attractive functions seem to be governed 

 by laws the same as the common laws of electrical attraction 

 and repulsion. The body possessing the positive energy be- 

 ing repelled by positively electrified surfaces, and attracted 

 by negatively electrical surfaces; and the body possessing 

 the negative energy following the contrary order. 



I have made a number of experiments with the view of 

 elucidating this idea, and of extending its application; and 

 in all cases they have tended to confirm the analogy in a 

 remarkable manner. 



Well burned charcoal, water, and nitric acid ; the same 

 substance, water, and solution of soda; made respectively ele- 

 ments of different electrical combinations, became distinctly 

 active when L 2Q alternations were put together : the positive 

 energy being exhibited ou the side of the alkali, and the nega- 

 tive on that of the acid. Arrangements of plates of zinc, pieces, 

 of moistened pasteboard, and moistened quicklime, to the 

 number of 40 series, likewise formed a weak electrical pile, 

 the effect of the lime being similar to that of an alkali, but 

 the power was soon lost. 



I endeavoured, by means of very delicate instruments, to 

 ascertain the electrical states of single insulated acid and 

 alkaline solutions, after their contact with metal's ; and for 

 this purpose I employed at different times the condensing 

 electrometer of Mr. Cuthbertson's construction, Mr. Ca- 

 vallo's multiplier, and a very sensible electrical balance, on 

 the principle of tortion, adopted by M. Coulomb; but the 



effects 



