Now let us cut off the current.  We are surprised to find a very weak extra current, a practical absence of self-induction on breaking, or, at least, a giving out of energy in nowise comparable to that on making.  Let us put on the current as it was before.  Another curious result.  But little self-induction now on making energy not absorbed.

Now cut off the current again.  Same effect as before.  Now let us put on the current reversed in direction.  At once we find a very strong counter potential or opposing self-induction developed.

The ring had been polarized, or retained its magnetic energy, and we are now taking out one set of lines and putting in reversely polarized lines of force.  This done, we break the reversed current without much effect of self-induction.  The ring remains polarized and inert until an opposite flow of current be sent through.  Iron is then a different medium from the ether.

The ring once magnetized must, in losing its magnetism, permit a closure of the lines by shortening.  This involves their passage from the iron across the space in the center of the ring, notwithstanding its great resistance to the lines of force.  As passage from iron to air is equivalent to lengthening of the lines, it is readily seen that such lengthening may oppose more effect than a slight shortening due to leaving iron, for air or space may give in provoking a closure and disappearance of the lines.  Looked at from another standpoint, the lines on the iron may actually require a small amount of initial energy to dislodge them therefrom, so that after being dislodged they may collapse and yield whatever energy they represent.

I must reserve for the future further consideration of the iron ring, but in thinking upon this matter I am led to think that the production of a magnetic line in an iron ring around a conductor may represent a sort of wave of energy, an absorption of energy on the evolution of the line from the conductor, and a slight giving out of energy on the line reaching that position of proximity to the iron ring, that its passage thereto may be said to be a shortening process or a lessening of its resistance.

The magnetism in air, gases, and non-magnetic bodies, being assumed to be that of the ether, this medium shows no such effects as those we get with the ring.  It does not become permanently polarized, as does even soft iron under the condition of a closed ring.  The iron possesses coercive force, or magnetic rigidity, and a steel ring would show more of it.  The molecules of the iron or steel take a set.  If we were to cut the soft iron ring, or separate it in any way, this introduction of resistance of air for ether in the magnetic circuit would cause the lines to collapse and set up a current in the conductor.  The energy of the ring would have been restored to the latter.  The curious thing is that physically the polarized ring does not present any different appearance or