ATTRACTION AND REPULSION OF MAGNETS. 11 



magnet disturbs a compass, another magnet may be so 

 placed as to neutralize the disturbance. Poles of a 

 horse-shoe magnet. 



The experiments proving these general laws are the 

 easiest of all. Turn the red end of a magnet held in 

 the hand towards the red end of a suspended needle 

 or compass-needle, and it repels the needle's red end. 

 In like manner, the blue end of the hand-magnet 

 repels the blue end of the needle. On the contrary, 

 turn the red end of the hand-magnet towards the blue 

 end of the needle, and it attracts the needle's blue end ; 

 and in like manner, the blue end of the hand-magnet 

 attracts the red end of the needle. 



The same principle may be exhibited in various 

 forms. If the red end of the hand-magnet be pointed, 

 from a distance, at right angles towards the middle of 

 the needle, it attracts the blue end and repels the red 

 end ; shewing (in addition to the law which we have 

 before us) that the ends of a magnet can act obliquely: 

 an important remark on which we will speak further. 

 If the hand-magnet be placed, at a distance, with its 

 center in the line of the needle produced, and its 

 direction transversal to that of the needle, it disturbs 

 the needle according to the same law. If the hand- 

 magnet be placed with its center vertically above or 

 vertically below the center of the needle, and its 

 direction transversal to that of the needle, the same 

 remark holds. All these experiments lead to the 

 Second Law of Magnetism ; that there is repulsion 



