1132 
0,96 b,. On further decrease of the volume 6 descends more rapidly 
— and when also a line has been drawn which starts from the 
origin, so from v= O at an angle of 45° to the v-axis, the conti- 
nually descending 6 curve will meet this line at 6 dyn. If 6, and 
bij, ave given, this curve is determined. If 6, should have the same 
value, and if bij, should be smaller, the curve lies lower throughout 
its course, and reversely if bjim is greater, the whole 6 curve lies 
ligher. 
Of course if there did not exist a similar cause for the variability 
of b, we might imagine a more irregular course in the different 6 
curves. But if such a cause is assumed, nobody will doubt of the 
truth of the abuve remarks. I have even thought I might suppose 
that there is a certain kind of correspondence possible in the course 
of the different 6 curves. The points of these curves which are of 
importance for the equation of state, run from v = bim to v=o. 
At a value of v= nbjm (and n can have all values between 1 and oo), 
b, — b is smaller as by — bim is smaller. Now I deemed it probable 
that there would be proportionality between these two latter quantities, 
and that therefore the following character of these curves can be put, viz. 
by = b ( (2) ) 
= | —— 1 
by — b lim U lim 
v 7 5 
and that this function of —— is the same, entirely or almost entirely. 
Viim : . 
When I considered the question what the meaning of this equation 
might be, the following thought occurred to me. Could possibly the 
quasi-association be the cause of this variability of 6 with the 
volume? 
I treated this quasi-association in an address to the Academy 
in 1906, and later on in some communications in 1910, and I came then 
to the conelusion that it must be derived from the increase of tension of 
the saturate vapour in the neighbourhood of the critical temperature 
that at every temperature and in every volume a so-called homo- 
weneous phase is not really homogeneous; but that dependent on the 
size of the volume and also on the temperature there are always 
aggregations of a comparatively large number of molecules which 
spread uniformly. In very large volume the number of these aggre- 
gations is vanishingly small and with small volume, and especially 
at low temperature this number increases greatly; so that at the 
limiting volume the number of free molecules has become vanishing 
small. If in each of these aggregations the value of 6 does not differ 
-much from bij, or perhaps coincides with it, the following value of 
