224 Prof. D. E. Hughes. Molecular Magnetism. [May 19, 



in such a manner as to produce the maximum loudness, and on taking 

 away the magnet we have comparatve silence as before. 



Heating the wire to nearly red heat by a spirit lamp increases the 

 tones of longitudinal magnetism induced by the coil some 25 per cent., 

 but it effects a much more marked increase in the tones produced by the 

 direct passage of the current, which are increased by more than 100 

 per cent. ; and if we pass the intermittent current through the coil 

 and constant through the wire, we find no direct rotation of the 

 molecules by heat. Although an apparent rotation takes place if, by 

 the required torsion, we first place the wire at its zero, for then on the 

 application of heat faint sounds are heard, which become again 

 almost silent on cooling, this is simply due to the diminution by heat 

 of the effect of the elastic torsion. 



Tempered steel gave exceedingly faint tones, requiring the use of 

 the microphone; but on magnetising with a constant current, inducing 

 spiral magnetism, the sounds became audible, some 15° sonometer 

 against 175° for iron; thus the molecular rigidity of steel as observed 

 by previous methods was fully verified. 



I have mentioned only a few of the numerous experiments I have 

 made by the three methods described, all of which, however, bear 

 directly upon the molecular arrangement of electric conducting bodies. 

 1 have selected a few bearing directly upon the subject I have chosen 

 for this paper. 



I nave, I believe, demonstrated by actual experiments which are 

 easy to repeat, that — 



1. An electric current polarises its conductor, and that its molecular 

 magnetism can be reconverted into an electric current by simple torsion 

 of its wire. 



2. That it is by the rotation of its molecular polarity alone that an 

 electric current is generated by torsion. 



3. That the path of an electric current through an iron or steel wire 

 is that of a spiral. 



4. That the direction of this spiral depends on the polarity of the 

 current, or that of its magnetism. 



5. That a natural magnet can be produced, having its molecular 

 arrangement of a spiral form, and consequently reversed electric 

 currents would both have a similar spiral in passing through it. 



6. That we can rotate the polarised molecules by torsion or a com- 

 pound strain of longitudinal and transversal. 



7. That the rotation or movements of the molecules give out clear 

 audible sounds. 



8. That these sounds can be increased or decreased to zero by means 

 that alone have produced rotation. 



9. That by three independent methods the same effects are produced, 

 and that they are not due to a simple change or weakening of polarity, 



