( 60 i ) 
heating. Mg and Rn shewed the above mentioned diminution in a 
marked manner between 500 and 600°. The results are collected 
in the table p. 600. The elements in square brackets have pre¬ 
viously been examined by others; the atomic weights in each 
column increase from top to bottom; the elements under column 
C show a constant susceptibility, under / a numeric increase on 
heating and under D a numeric decrease. The fewest number (4) 
of elements appears in the fifth column, in the case of which the 
susceptibility increases on heating, the increase being, however, very 
small in each instance. 
From a thermomagnetic point of view a certain relation also exists 
in connection with the periodic curve x — funct. (a): the paramagnetic 
elements under D all lie at the principal maxima or at the secondary 
peaks; on the contrary, those under I lie on the ascending branches 
of the curve. Therefore the sharpness of the bends would be flattened 
more and more at higher temperatures; probably at lower tempe¬ 
ratures they would become more accentuated, and it may be that 
only then do they attain their most characteristic shape; of course 
the temperature of -j-18 3 is quite arbitrary. Concerning Curie’s 
rules the following statements may be made: 
1. Only palladium foil from Kahlbaum, with 0,707 0 of iron and 
X = -j- 6,12, on heating followed, more or less, Curie’s law, but on 
cooling it shewed complications. With much purer palladium from 
Dr. Hkraeus, with 0,03% iron and x — + the susceptibility 
fell less rapidly than would follow from Curie’s rule; temperature- 
hysteresis was not observed on cooling 1 ). 
2. There are only 6 diamagnetic elements which do not vary 
within the whole temperature-range. Of these P, S and Se had already 
been experimented upon by Curie. 
3. On melting or solidifying, sometimes — not always — a dis¬ 
continuity appears, which can be classified under one or other of the 
two following divisions: I, a large or small leap in the curve of 
X itself, as with P (44°), Ag (961 c ), Sn (233 ), Sb (631°), Te (450% 
Au (1064°), T1 (290'), Pb(327°), Bi(268°); II, a rather sudden change 
of d'/L/dO as with Mg (633°), Cu(1065 c ), Cd (322°), 1(114°); with 
regard to sulphur, the curve at the melting-point departs slightly from 
its otherwise absolutely rectilineal character, which variation was 
probably overseen by Curie. 
b By chance palladium is the only paramagnetic elen 
perhaps it was not pure enough. The important results 1 
netic metals at very high temperatures and also for the 
nt examined by Curie; 
* oxygen, for ferromag- 
salts crystallised or in 
