128 On some new Eleclro-chemical VhcBUomena. 



distance of about six inches asunder, and propelling a current of 

 the gas through a small tube between them. If the electrical 

 machine is not in too powerful action, the positive ball is instantly 

 reddened, while the blue colour of the negative surface remains 

 unaltered. 



11. Nitrous acid gas exhibited the same appearances as mu- 

 riatic acid. 



12. Potassium in a state of combustion was placed between 

 the electrified surfaces. Its flame, and the alkaline fumes it 

 produces, were drawn to the negative conductor. 



13. Ammonia aiforded no very distinct results. 1 attempted 

 to ascertain its electrical state by disengaging it through a small 

 tube placed between the conductors, the atmosphere being slightly 

 tainted with miniatic acid ; but it was apparently equally at- 

 tracted and repelled by the electrical surfaces. When the con- 

 ductors were coated with turmeric paper, the negative appeared 

 sooner reddened than tlie positive, but in a very short time the 

 efl'ect upon each became ecjual. 



14 Benzoic acid evolved by gently heating benzoin between 

 the electrical poles, was attracted to the positive side ; but when 

 the balsam took fire, the flame and carbonaceous matter were 

 immediately drawn in an opposite direction. 



I heated some pure benzoic acid placed upon a silver capsule, 

 between the balls ; as long as the temperature was only sufficient 

 to raise it in vapour, it took the positive direction : but the mo- 

 ment that the acid was inflamed, the carbonaceous fumes passed 

 to the ".egative side. 



15. Camphor during its combustion throws off a large quan- 

 tity of charcoal, and, when burned between the opposite electrical 

 surfaces, ftirnishes a good irjstance of the attraction of that sub- 

 stance by the negative pole, which soon becomes coated with it,^ 

 the positive ball being much less soiled. 



16. The resinous bodies in general exhibited the same ap- 

 pearances as camphor : when in a state of combustion, both the 

 flame and smoke were repelled by the positive, and attracted by 

 the negative pole. 



17. Amber, on the contrary, presented pha?nomena nearly 

 similar to those of benzoin. When brought into n state of fusion, 

 its acid vapour was attracted by the positive ball; but when made 

 to burn, an opposite effect was produced. 



§IV. 

 la the preceding detail of experiments, such only have been se- 

 lected as were attended with marked results. The electrical energies 

 of many other sabstances were examined and compared, but no 

 new facts were ascertained, nor were any circumstances observed 



wliich 



