1903-4.] Prof. Knott on Effect of Transverse Magnetization . 293 
when the temperature approached that at which nickel ceases to 
be strongly magnetic. 
The nature of the phenomenon is indicated in the following table, 
which gives the change of resistance of 100,000 ohms of nickel 
wire at the temperatures shown when the wire is subjected to 
a transverse magnetic field of about 3800 units. 
Temperature. 
Resistance change 
in Field 3800. 
Temperature. 
Resistance change 
in Field 3800 
10° C. 
750 
320° C. 
320 
100 
640 
330 
270 
200 
390 
335 
170 
250 
250 
340 
100 
290 
190 
345 
40 
300 
201 
350 
5 % 
310 
250 
The peculiarity consists in the marked minimum at temperature 
290° and the still more abrupt maximum at temperature 320°. 
The very rapid fall off to zero as the temperature rises from 330 
to 350 is also worthy of note. So limited is the range of 
temperature within which these changes take place, that the 
phenomenon might easily have escaped notice. It was fortunate 
that in one of the earlier series a temperature very near the 
minimum point was hit upon. The peculiarity was at first 
ascribed to the inherently greater difficulties of making the 
experiments at the higher temperatures : but time after time, by 
means of small successive changes of temperature between the 
critical limits, exactly the same results were obtained. There can, 
therefore, be no doubt as to the existence of a peculiar molecular 
change as the nickel wire is raised in temperature from about 
290° to 350". In my paper on the effect of longitudinal 
magnetization (see especially the curves at the highest temperatures, 
p. 46, l.c.), a similar peculiarity was indicated. It was, however, 
so slight — being merely a slight upward bulging of the isodynamic 
curves — that it was not at the time regarded as of any moment, 
but, in the light' of the present result, it can no longer be looked 
upon as due to small errors of measurement. 
