ON THE MEASUREMENT OF MAGNETIC HYSTERESIS. 
77 
1 
Ho. 
Bo. 
Ho. 
Bo. 
W. 
Ho. 
Bo. 
W. 
37-40 
14550 
47050 
18-00 
10480 
23800 
8-00 
2870 
2780 
32-05 
13980 
42600 
16-00 
9360 
19100 
7-00 
2110 
1700 
27-95 
13350 
38200 
14-00 
8080 
14820 
6-00 
1400 
780 
25-18 
12800 
34900 
12-00 
6390 
10020 
5-00 
950 
190 
22-00 
12010 
30600 
10-00 
4600 
5830 
20-00 
11160 
26600 
9-00 
3690 
4100 
§ 55. Effect of Torsion, ivitliin the Elastic Limit, upon the Steel Rod. —-Thes teel rod 
was now subjected to torsion in the way described in § 53. A load not exceeding 
2000 grammes was bung from the rim of the wheel and was increased and diminished 
by steps of 100 or 200 grammes, care being taken to make the changes in the load 
with as little jerking as possible. For 
each cycle of loading and unloading the 
maximum magnetic force Hg was kept 
at a constant value. In every case, 
except possibly that of Hg = 37‘4, the 
wire was put through several cycles of 
twist in which the load varied between 
the limits dz 2000 grammes, and then 
the magnetising current was put through 
20 cycles of reversal before the observa¬ 
tions for Bg and W were made. The 
positive and negative signs indicate that 
the weio’hts were huno- on the rmht- and 
o O o 
left-hand sides of the wheel respectively. 
In the actual experiments on the effect 
of torsion on Bg and W the torsion was 
always positive, the load being initially 
zero, then increasing to 2000 grammes, 
and then decreasing to zero. In the 
ideal case of perfect symmetry about tlie 
state of no torsion, the part of the curve 
for negative torsions would be exactly 
similar to the part of the curve for posi¬ 
tive torsions. The residts are given in 
the following table, and are exhibited in 
fio’. 0 :—- 
