348 FRAGMENTS OF SCIENCE. 



resuspend it, and repeat your former experiment. You 

 now find that each extremity of the magnet attracts 

 one end of the needle, and repels the other. The sim- 

 ple attraction observed in the first instance, is now re- 

 placed by a dual force. Eepeat the experiment till you 

 have thoroughly observed the ends which attract and 

 those which repel each other. 



Withdraw the magnet entirely from the vicinity of 

 your needle, and leave the latter freely suspended by 

 its fibre. Shelter it as well as you can from currents 

 of air, and if you have iron buttons on your coat, or a 

 steel penknife in your pocket, beware of their action. 

 If you work at night, beware of iron candlesticks, or 

 of brass ones with iron rods inside. Freed from such 

 disturbances, the needle takes up a certain determinate 

 position. It sets its length nearly north and south. 

 Draw it aside and let it go. After several oscillations 

 it will again come to the same position. If you have 

 obtained your magnet from a philosophical instrument 

 maker, you will see a mark on one of its ends. Sup- 

 posing, then, that you drew your needle along the end 

 thus marked, and that the point of your needle was 

 the last to quit the magnet, you will find that the point 

 turns to the south, the eye of the needle turning to- 

 wards the north. Make sure of this, and do not take 

 the statement on my authority. 



Now take a second darning-needle like the first, 

 and magnetise it in precisely the same manner: freely 

 suspended it also will turn its eye to the north and 

 its point to the south. Your next step is to examine 

 the action of the two needles which you have thus 

 magnetised upon each other. 



Take one of them in your b.and, and leave the 

 other suspended; bring the eye-end of the former near 

 the eye-end of the latter; the suspended needle re- 



