230 On some Cliemical Agencies of Electricity , 



after being laid upon a surface of mercury, and then separated. 

 Tin, zinc, and copper, which adhere much more strongly* 

 communicate higher charges to the condensing electrometer. 

 I have had no instrument sutTicientlv exact to measure the 

 difTerences ; but it would seem that the adhesion from the 

 difference of electrical stales must have operated in these 

 experiments*, which being proportional to the electrical 

 energies are, on the hypothesis before stated, proportional 

 to the chemical affinities. How far cohesion in general may 

 be influenced or occasioned by this effect of the difference of 

 the electrical energies of bodies, is a curious question for in- 

 vestigation. 



Many applications of the general facts and principles to 

 the processes of chemistry, both in art and in nature, will 

 readily suggest themselves to the philosophical inquirer. 



They offer very easy methods of separating acid and alka- 

 line matter, when they exist in combination, either together 

 or separately, in minerals ; and the electrical powers of de- 

 composition may be easily employed in animal and vegetable 

 analysis. 



A piece of muscular fibre, of two inches long and half an 

 inch in diameter, after being electrified by the power of 130 

 for five days, became perfectly dry and hard, and left on in- 

 cineration no saline matter. Potash, soda, ammonia, lime, 

 and oxide of iron were evolved from it on the negative side, 

 and the three common mineral acids and the phosphoric acid 

 were given out on the positive side. 



A laurel leaf treated in the same manner, appeared as if 

 it had been exposed to a heat of 500° or 600° Fahrenheit, 

 and was brown and parched. Green colouring matter, with 

 resin, alkali, and lime, appeared in the negative vessel : and 

 the positive vessel contained a clear fluid, which had the 

 smell of peich blossoms j and which, when neutralized by 

 potash, gave a blue-green precipitate to solution of sulphate 

 of iron j so that it contained vegetable prussic acid. 



A small plant of mint, in a state of healthy vegetation, 



* Amalgamation undoubtecUy must have interfered ; but the general result 

 Tccme to have been distinct. 



