BitowN — Mechanical Stress and Magnetisation of Iron. 183 



maximum current density employed in all tlie wires was at the rate of 100 

 amperes per sq. cm., and to obtain a measure of the circular magnetisation 

 the results were all plotted on millimetre paper, so that two centimetres 

 represented one ampere on the axis of abscissae, and on the axis of ordinates 

 one centimetre represented ten divisions of deflection or twist on the scale. 



im^M0m^m^^^^m 



m^^w^^^w 



As was shown in Part I. of this paper,' this method of stating the results 

 jives a very symmetrical cyclic curve; and one would expect that an iron 



1 Scient. Proc. Eoy. Dublin Soc, 1909, vol. xii., p. 101. 

 SCIENT, PKOC. R.D.S., VOL. XII., NO. XVII. 



2h 



