268 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? 
AVhat 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; 
