Brown — Mechanical Stress and Magnetisation of Iron. 107 



of the circular magnetisation produced by the toi'sion of the wire in a 

 magnetic field. 



Table II. is an example of one of the sets of observations taken for a 

 complete cycle when the load on the wire was 9'9 x 10* grammes per 

 sq. cm. 



Table II. 



This was the best and most symmetrical cycle obtained in the whole 

 series of ninety or so. In most of the other cases the axis of abscissse had to 

 be shifted down from two to eight scale-divisions, so as to make the curve 



