518 



Scientific Proceedings, Royal Dublin Society. 



Note added Novi-mher, 1910. — In continuation of tliis work a fresh nickel 

 wire was prepared in the usual manner, to give the degree of magnetic 

 softness between Hj and Hj of the arbitrary scale used above, and was tested 

 when subjected to six different longitudinal loads, in longitudinal magnetic 

 fields up to 200 c.g.s. units. The current sent through the wire was at the 

 same rate as before, viz. 100 amperes per sq. cm. ; and it was found that the 

 relation between the longitudinal magnetic field in which the maximum 

 twist occurs, and the longitudinal load on the wire when it was being tested, 

 still follows very approximately the straight-line law ; but the maximum 

 twist attains its highest value when the load on the wire is at the rate of 

 4 X 10^ grammes per sq. cm., as shown in the following table : — 



