( &34 ) 
mixtures of liquid oxygen with non-magnetic gases should obey the 
thermodynamic laws that govern the number of such complexes. 
But all this must be established by further experiments which we 
hope to complete; in the meantime the most probable assumption is 
the old one that the specific susceptibility is independent of the 
pressure. 
As regards the question as to whether the specific susceptibility 
at lower temperatures still follows the law of inverse proportionality 
to the root of the absolute temperature, if the ferro-magnetism with 
a very low-lying Curie point according to Weiss’s theory of corre¬ 
sponding magnetic states does not exist, then the change to a still 
slower increase with decreasing temperature 'and the approximation 
to a limiting value is, perhaps, more probable. 
The law of T 7- * at once gives rise to the question if instead of 
the Langevin elementary magnets whose intensity is independent of 
the temperature, we should assume that their intensity varies directly 
as \/T\ that is, that we should assume the existence of elementary 
currents or electrons moving in their paths with speeds proportional 
to (and, therefore, determined by) the speeds of molecular heat 
motions. In other words, while Langevin’s theory already supposes 
that the planes in which the electrons move follow the motions of 
the molecules, but that the areas described in those planes are still 
independent of heat motion, we should now assume that the electrons 
undergo the influence of heat motion at their motion in their paths, 
and, if the radius of their path has also become invariable, revolve 
while remaining in the same position with respect to the atom; they 
would be electrons that are .frozen fast to the atom, an assumption 
that has already been made to explain other phenomena. 
This addition to Langevin’s theory, however, does not lead to a 
specific susceptibility proportional to T~* as one at first sight would 
be inclined to think, but to a constant specific susceptibility. 
To substantiate that addition it will probably be necessary to proceed 
to still lower temperatures than those of our experiments. It seems 
at present that it is not impossible' that then the law x proportional 
to T~ * changes to x = const.-, our observations on solid oxygen seem 
to indicate a change in this direction. The assumption to which this 
is equivalent: viz, that the magnetic motions of the electrons cease 
at the absolute zero, and to which our experiments seem to lead, is 
much more satisfactory than that the magnetic motions of the elec¬ 
trons still persevere even at the absolute zero. 
The second question to which we devoted attention — the depen¬ 
dence of susceptibility upon field strength requires no detailed treat- 
