Primary Laws. 8r 



is more familiar than polarity, and yet in its far-reach- 

 ing consequences probably none is so little under- 

 stood. The chief facts are as follows : — 



If the north pole of a fixed magnet and the north 

 point of a magnetic needle meet, the north point of 

 the needle is repelled and the south point attracted, 

 and vice-versa. This action with all magnets is 

 invariable. Again, if a horse-shoe magnet be dipped 

 in iron filings, the filings adhere and build an armature 

 between the poles. If the north poles of two bar- 

 magnets be dipped in iron filings and held near one 

 another, the filings on each magnet repel one another ; 

 if opposite poles meet, the filings attract one another. 

 It thus follows that while each magnet has only two 

 poles, its energy is actually quadruple, for each pole 

 exerts a dual energy by both attracting and repelling 

 according to conditions. 



What the law of polarity involves shall be best 

 explained in a series of propositions, as follows : — 



First Proposition. — If tJic principle of energy in an 

 iron magnet be polarity, and if the same principle be 

 also resident in an atom of iron, because it is also a 

 magnet, then the force or cohesion r which binds atom to 

 atom atomically must also be polarity. 



If the evidence heretofore advanced be true, this 

 proposition is indisputable. If an atom of iron be a 

 magnet with two poles, the law of atomic polarity, 

 or the law governing atoms in their aggregation or 

 invisible structural cohesion, must be similar to 

 magnetic polarity, or the law governing visible 



F 



