SUPERPOSED MAGNETISMS IN IRON AND NICKEL. 



195 



Experiment V. Linear Current = 4 - 068. 



Helical Current, 



0-410 



0-700 



1-254 



1-891 



2-385 



3-039 



4-214 



Twist, 



390 



810 



1303 



1678 



1802 



1886 



1884 



Three series were taken with steady helical current and varying linear 

 current. They are as follows : — 



Group B. 

 Experiment I. Helical Current = '611 Amp. 



Linear Current, 



0-410 



0-716 



1-272 



1-943 



2-395 



3-051 



3-899 



Twist, 



126 



357 



742 



1030 



1125 



1197 



1225 



Experiment II. Helical Current = 1-987 Amp. 



Linear Current, 



0-418 



0-750 



1-276 



1-948 



2-364 



2-970 



3-803 



Twist, 



127 



312 



767 



1190 



1358 



1576 



1754 



Experiment III. Helical Current = 3-229. 



Linear Current, 



0-505 



0-893 



1-320 



1-703 



2-724 



Twist, 



152 



387 



718 



877 



1367 



In both these series the wire was under a tension of 1950 grammes' weight. 

 The representative curves are shown on Plate XXIX., iron groups A. and B. 

 The current strengths of the varied current are laid clown horizontally, and 

 the corresponding twists vertically. The two series differ markedly, the 

 A group showing a maximum twist for an intermediate current strength, the 

 B group giving no such indication. That such a difference between the two 

 cases should exist is not to be wondered at, since the magnetisation due to a 



