292 Proceedings of Royal Society of Edinburgh. [sess. 
Effect of Transverse Magnetization on the Resistance of 
Nickel at High Temperatures. By Professor C. G. 
Knott. 
(Read June 20th, 1904.) 
Abstract. 
In a previous communication * it was pointed out that the effect 
of transverse magnetization on the resistance of nickel wire was 
inappreciable in fields below 500 C.G.S. units, thereby differing 
from the case of longitudinal magnetization, in which the effect was 
easily measurable in fields below 20. f The reason of this is no 
doubt to be referred to the thinness of the wire in the direction of 
the magetizing force. To measure the effect of transverse magnet- 
ization it was necessary to form a flat coil and insert it between 
the poles of a powerful electro-magnet. Considerable difficulty 
was experienced in winding this coil with interwound asbestos in- 
sulation, for great care had to be taken that no part of the wire 
cut the lines of force obliquely, otherwise there would be a resolved 
component of longitudinal effect, which in certain cases might 
altogether mask the effect looked for. The coil used in the final 
experiments was suitable in all respects. It was coiled between 
glass plates, the successive coils being separated by threads of 
asbestos. Round the coil another coil (of Beacon wire) was wound 
anti-inductively, so that any current passing through it would have 
no magnetic action upon the nickel wire inside. By varying the 
current in this external coil I was able to heat the nickel to any 
desired temperature uj3 to 400° C. In any one experiment the 
final temperature came to a steady state, and not till this state was 
reached was it possible to begin the observations on the resistance 
change. This was measured in the manner already described in 
my paper on the effect of longitudinal magnetization, and it will 
suffice meanwhile to call attention to a remarkable result obtained 
* Proc., vol. xxiv. p. 501 (1903). 
t Trans., vol. xli. pp. 39-52 (1904). 
