<>GS FRAGMENTS OF SCIENCE. 



upper half attracts the opposite end. Supposing the 

 north end of your little needle to be that attracted below, 

 you infer that the entire lower half of your magnetized 

 strip exhibits south magnetism, while the entire upper 

 half exhibits north magnetism. So far, then, you have 

 determined the distribution of magnetism in your strip of 

 steel. 



You look at this fact, you think of it; in its suggestive- 

 ness the value of an experiment chiefly consists. The 

 thought naturally arises: '* What will occur if I break my 

 strip of steel across in the middle? Shall I obtain two 

 magnets each possessing a single pole?" Try the experi- 

 ment; break your strip of steel, and test each half as you 

 tested the whole. The mere presentation of its two ends 

 in succession to your test-needle suffices to show that you 

 have not a magnet with a single pole that each half 

 possesses two poles with a neutral point between them. 

 And if you again break the half into two other halves, you 

 will find that each quarter of the original strip exhibits 

 precisely the same magnetic distribution as the whole strip. 

 You may continue the breaking process: no matter how 

 small your fragment may be, it still possesses two opposite 

 poles and a neutral point between them. Well, your hand 

 ceases to break where breaking becomes a mechanical 

 impossibility; but does the mind stop there? No: you 

 follow the breaking process in idea when you can no longer 

 realize it in fact; your thoughts wander amid the very 

 atoms of your steel, and you conclude that each atom is a 

 magnet, and that the force exerted by the strip of steel is 

 the mere summation, or resultant, of the force of its 

 ultimate particles. 



Here, then, is an exhibition of power which we can call 

 forth at pleasure or cause to disappear. We magnetize our 

 strip of steel by drawing it along the pole of a magnet; we 

 can demagnetize it, or reverse its magnetism, by properly 

 drawing it along the same pole in the opposite direction. 

 What, then, is the real nature of this wondrous change? 

 What is it that takes place among the atoms of the steel when 

 the substance is magnetized ? The question leads us beyond 

 the region of sense, and into that of imagination. This 

 faculty, indeed, is the divining-rod of the man of science. 

 Not, however, an imagination which catches its creations 

 from the air, but one informed and inspired by facts; 



