THE SIX GATEWAYS OF KNOWLEDGE. 261 



They asked themselves, Is it conceivable, that if a 

 piece of copper can scarcely move through the 

 air between the poles of an electro-magnet, a 

 human being or other living creature placed there, 

 would experience no effect ? Lord Lindsay got 

 an enormous electro-magnet made, so large that 

 the head of any person, wishing to try the experi- 

 ment, could get well between the poles, in a region 

 of excessively powerful magnetic force. What was 

 the result of the experiment? If I were to say 

 nothing! I should do it scant justice. The result 

 was marvellous, and the marvel is that nothing was 

 perceived. Your head, in a space through which 

 a piece of copper falls as if through mud, perceives 

 nothing. I say this is a very great wonder ; but I 

 do not admit, I do not feel, that the investigation 

 of the subject is completed. I cannot think that 

 that quality of matter in space magnetisation 

 which produces such a prodigious effect upon a 

 piece of metal, can be absolutely without any 

 it is certainly not without any effect whatever 

 on the matter of a living body ; and that it can 

 be absolutely without any perceptible effect what- 



