68 FARADAY 



see that it is the colored end of the needle which is pulled 

 toward it. We are now, therefore, dealing with two kinds of 

 power, attracting different ends of the magnet a double 

 power, already existing in these bodies, which takes up the 

 form of attraction and repulsion. And now, when I put up 

 this label with the word MAGNETISM, you will understand 

 that it is to express this double power. 



Now with this loadstone you may make magnets arti- 

 ficially. Here is an artificial magnet (Fie. 39) in which both 

 ends have been brought together in order to increase the 

 attraction. This mass will lift that lump of iron, 

 and, what is more, by placing this keeper, as it is 

 called, on the top of the magnet, and taking hold 

 of the handle, it will adhere sufficiently strongly 

 to allow itself to be lifted up, so wonderful is its 

 power of attraction. If you take a needle, and 

 just draw one of its ends along one extremity of 

 the magnet, and then draw the other end along 

 the other extremity, and then gently place it on 

 the surface of some water (the needle will gen- 

 erally float on the surface, owing to the slight 

 greasiness communicated to it by the fingers), you 

 able to get all the phenomena of attraction and 

 repulsion by bringing another magnetized needle near to it. 



I want you now to observe that, although I have shown 

 you in these magnets that this double power becomes evident 

 principally at the extremities, yet the whole of the magnet is 

 concerned in giving the power. That will at first seem rather 

 strange; and I must therefore show you an experiment to 

 prove that this is not an accidental matter, but that the whole 

 of the mass is really concerned in this force, just as in fall- 

 ing 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 FJG 



in opposite 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 



