DISTRIBUTION OF POWER IN MAGNETS. 119 



falling the whole of the mass is acted upon by 

 the force of gravitation. I have here (fig. 40) a 

 steel bar, and I am going to make it a magnet, 

 by rubbing it on the large magnet (fig. 39). I 

 have now made the two ends magnetic in oppo- 

 site ways. I do not at present know one from 

 the other, but we can soon find out. You see 

 when I bring it near our magnetic needle (fig. 38) 

 one end repels and the other attracts ; and the 

 middle will neither attract nor repel it cannot, 

 because it is half way between the two ends. 

 But now, if I break out that piece (n. s.) and 

 then examine it see how strongly one end (n) 

 pulls at this end (sfig. 38) and how it repels the 

 other end (N). And so it can be shown that 

 every part of the magnet contains this power of 

 attraction and repulsion, but that the power is 

 only rendered evident at the end of the mass. 

 You will understand all this in a little while, 

 but what you have now to consider is that every 

 part of this steel is in itself a magnet. Here is 

 a little fragment which I have broken out of the 

 very centre of the bar, and you will still see 

 that one end is attractive and the other is re- 

 pulsive. Now, is not this power a most wonder- 

 ful thing? And very strange, the means of 



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