274 FRAGMENTS OF SCIENCE. 



as you can never in reality thus detach' your north magnet- 

 ism from its neighbor. But supposing us to have done so, 

 what would be the action of the two poles of the magnet 

 on nf Your reply will of course be that the pole s attracts 

 n while the pole sr repels it. Let the magnitude and direc- 

 tion of the attraction be expressed by the line n m, and the 

 magnitude and direction of the repulsion by the line n o. 

 Now, the particle n being equally distant from s and ]sr, 

 the line n o, expressing the repulsion, will be equal to m n, 

 which expresses the attraction. Acted upon by two such 

 forces, the particle n must evidently move in the direction 

 n p, exactly midway between m n and n o. Hence you see 

 that although there is no tendency of the particle n to 

 move toward the magnetic equator, there is a tendency on 

 its part to move parallel to the magnet. If, instead of a 

 particle of north magnetism, we placed a particle of south 

 magnetism opposite to the magnetic equator, it would evi- 



FIG. 11. 



dently be urged along the line n q; and if, instead of two 

 separate particles of magnetism we place a little magnetic 

 needle, containing both north and south magnetism, opposite 

 the magnetic equator, its south pole being urged along 

 n q, and its north along n p, the little needle will be com- 

 pelled to set itself parallel to the magnet s N. Make 

 the experiment, and satisfy yourselves that this is a true 

 deduction. 



Substitute for your magnetic needle a bit of iron wire, 

 devoid of permanent magnetism, and it will set itself 

 exactly as the needle does. Acted upon by the magnet, 

 the wire, as you know, becomes a magnet and behaves as 

 such; it will turn its north pole toward p, and south pole 

 toward q, just like the needle. 



But supposing you shift the position of your particle 

 of north magnetism, and bring it nearer to one end of 



