1883.] Theory of Magnetism based on New Researches. 199 



magnetic meridian. At E we have a longitudinal neutrality produced 

 in the same rod when placed magnetic west, the polarity in the latter 

 case being transversal. 



In all these cases we have a perfect symmetrical arrangement, and 

 I have not yet found a single case in well-annealed soft iron in which 

 I could detect a heterogeneous arrangement, as Wiedemann supposes, 

 in the case of neutrality. 



We may observe this symmetry without the aid of the induction 

 balance ; for, if we magnetise a rod under torsion (which we have 

 already shown produces an ultimate rigidity), and observe the effects 

 upon a directive needle, we find that every portion is equally mag- 

 netised, and in the same symmetrical arrangement of its molecules. 

 We can also observe the probable existence of the double molecule, A, 

 fig. 6, by magnetising a rod with feeble magnetic power. We then 

 find a certain degree of magnetism, which is of exactly the same force 

 as that produced when magnetised under a right-hand torsion, and if 

 now we again magnetise it under a left-hand torsion, we have still the 

 same force. This, without the existence of a double molecule, would 

 have required a far greater inducing magnetic power to have rotated 

 the molecules to the same degree under a contrary torsion. The limits 

 of this paper do not allow me to bring further proofs of the existence 

 of the double molecule, which the induction balance plainly indicates, 

 as it requires a separate paper on this subject alone. If we consider 

 the fire magnets of Dr. Hooke, we know that we cannot produce 

 neutrality by heat, that we cannot melt or manufacture iron, except 

 under the influence of the earth's directive influence, and that we can 

 only produce apparent neutrality by vibrations or- torsions, allowing, 

 by the molecular freedom thus given, a complete closed circle or 

 attractions, as at A or C, and that a similar apparent neutrality arises 

 from the superposed magnetism of B, or the tranversal F, both of 

 which in small wires or rods are apparently completely neutral. 



We can produce a perfectly symmetrical closed circle of attractions 

 of the nature of the neutrality of C, fig. 6, by forming a steel wire 

 into a closed circle, 10 centims. diameter, if this wire is well joined 

 at its extremities by twisting and soldering. We can then magnetise 

 this ring by slowly revolving it at the extremity of one pole of a 

 strong permanent magnet, and to avoid consequent poles at the part 

 last touching the magnet, we should have a graduating wedge of 

 wood so that whilst revolving it may be gradually removed to greater 

 distance. This wire will then contain no consequent points or external 

 magnetism, it will be found perfectly neutral in all parts of its closed 

 circle ; its neutrality is similar to C, fig. 6, for if we cut this wire at 

 any point we find extremely strong magnetic polarity, the wire being 

 magnetised by this method to saturation and having retained (which 

 it will indefinitely) its circle of attractions complete. 



