MAGNETIC AND ELECTRIC CURRENTS. I 1 7 



of organic substances is produced without the 

 intervention of molecules of nitrogen, by intensi- 

 fying the solar action by a lens on a sheet of white 

 paper ; which is speedily turned brown and black 

 by driving off the molecules of hydrogen and 

 oxygen, and leaving the charcoal. 



A remarkably unstable electro-static condition 

 of molecules of hydrogen and of chlorine exists 

 when mingled together; which a gleam of sun- 

 shine disturbs, producing their instantaneous 

 union with explosive force. 



RECIPROCAL ACTION BETWEEN ELECTRIC CURRENTS 

 AND MAGNETIC CURRENTS. 



That there are electric currents continually 

 circling about the axis of a magnet, as about the 

 axis of the earth, is proved by its pro- ,,'>> 

 ducing the same reaction as if a / \^ 



spiral conducting-wire were wound lx X/ 

 around it, transmitting a continuous i^U^i 

 current from a voltaic battery. The >( X 



currents circulate in the same uni- % "-iEK JB 



form direction about the axis of a \ 



---_>- 



magnet ; but they appear to move in . Figf 35 . 

 opposite directions, when a bar-magnet is bended 

 to the form of a horse-shoe, as represented in Fig. 

 35. It may be noticed that the currents about 

 the s pole, when facing the observer, move in the 

 same direction that the hand of a watch moves 

 about the dial-plate, and those about the N pole 



