( 803 ) 
Such an influence’) would occur, if the specifie entropy of the parts 
of the reacting mixture should be changed by the catalytic agent, 
but not the specifie energy. The mutual entropy of the system 
‘atalytic agent + reacting mixture in the ideal gas state would have 
another value in this case, than is given by Gipes’s paradox, while as 
usually in the ideal gas state no mutual energy would occur. To explain 
this we should have to accept a change of the chemical volumes (Bourz- 
MANN’S “kritische Räume”’) of the reacting mixture by the catalytic agent. 
A modified intermediate state would, of course, occur here too; 
hence the equilibrium will be reached with another velocity, 
3. By the addition of a substance which does not take part in the 
reaction also the specific energy of the reacting substances is changed 
either because only the mutual attraction in the mixture becomes 
different — new «a’s appear in the equation of state — or because 
stronger causes are active (association of the solvent with one of the 
reacting substances). Of course also the velocity of reaction will change 
in both cases. To this category belong all “milieu” influences, of 
course, (e. g. changes of electrolytic dissociation with change of 
solvent). Also the displacements of the equilibrium under influence 
of light or electric discharges may belong to it, e.g. the light-equili- 
brium of sulphur in CS,, which sets in with a certain intensity of 
illumination, and which returns to its former state when the old 
state of illumination is restored. Here too it must be assumed that 
in consequence of the illumination the energy of the reacting sub- 
stances is modified *). 
4. The last mentioned cases, however, can also belong, either all 
of them or partly, to another category. For it is possible that they 
are no real equilibria, but are in the same relation to them as the 
case of the “osmotic temperatures” to that of real equilibrium, or 
in other words that the modified state must always be accompanied 
by a “current of energy”, an absorption of heat or electric energy * 
and emission of heat. Then the displacement would not be maintained 
1) We wilt leave it an open question whether the cases cited as such in the 
literature should not really be ranged under 3, but think that we should at least 
mention this possibility for completeness’ sake because the considerations of van ‘2 
Horr le. p. 21 which indeed only seem to be intended for heterogeneous catalysis, 
do not prove as far as we can see, that a case of homogeneous catalysis of tius 
kind is excluded by the second law of thermodynamics. 
2) Cf. Smrrs. These Proc. XII p. 356. Of course the false equilibria, which are 
reduced to the absolutely stable state by light or an electric spark do not belong 
to this category; they belong under lL. 
