Lecture on a new properly of Magnetism, 531 



moves one way this must repel it. The needle is at the axis ; I am 

 not touching it, but the moment I bring up this pole of the magnet 

 I send it round. Merely by the repulsion of that pole, making and 

 unmaking the magnet, by acting upon the bismuth I can repel it 

 from the magnet. This is utterly unlike what you saw with the iron. 

 When I drew off the iron cylinder, it went back with great power, I 

 could not pull it from the pole ; but here the power of the magnet is 

 to repel, not to attract. I am not acting by the north pole of one 

 magnet upon the north pole of another. I am taking a substance in 

 its natural state, not magnetic, and acting on a pole, and we have 

 found a substance which is repelled by the magnet, and not attracted. 

 Up to this time you have known of no substance but what was either 

 attracted by the magnet or indifferent to it : I have shewn you the 

 indifference of copper, except a current is going through it, but now 

 I show you another property, I show you repulsion, and I could, if I 

 had time, show that this property is universal, far more so than any- 

 thing you have seen before. Although not so great in amount, 

 nevertheless it is a power equal to gravity, it is even greater than 

 gravity in the mass with which we are now concerned. 



I will show you one other substance, and very different to the 

 metals, in order that you may see the effect. I will take a piece 

 of phosphorous. Phosphorous is rather a delicate thing to handle, 

 especially in warm weather like this ; nevertheless, I should like 

 to give you a proof that substances, other than metals, have this pro- 

 perty, because I want to show that all bodies are affected. We shall 

 succeed as soon as I get the larger part of the instrument into the 

 chamber. Though the indicating cylinder is the same, you will soon 

 see the action that takes place, and if I get the action I will not 

 care about the rest. First, I bring up this pole ; on making contact, 

 there is the repulsion. By unmaking and remaking it is stopped by 

 the reaction, only it does not touch, and now you see it is repelled 

 again. I might take you to hundreds of bodies and find them 

 all attracted as iron is, or repelled as bismuth and phosphorous 

 are. There is no one body that is not subject to the one or other 

 action of magnetic force. It is an universal law of nature that every 

 body in a solid or licpiid state is attracted or repelled by magnetic 

 force. 



