( 1219 ) 
while Sypnry Youre gives the value 4.26 for s. For propylalcohol 
I have chosen /;, equal to 7.78, which differs greatly from KurNeN’s 
value 3.93. The value thought probable by me agrees almost entirely 
with 3.39 instead with 3,93. According to the above relation s —= 4 
corresponds to it, while SYpnNry Youre gives s = 3,998. So tested by the 
above relation propyl-aleohol would already be a normal substance. 
But for acetic acid, for which at low temperatures the saturate 
vapour already consists almost entirely of double molecules, the 
relation does not hold at all. 
If it is taken into consideration that the values of /, printed 
unmodified in the above table are mean values, which may only 
accidentally be the values of /, —I feel justified in assuming that 
Gin 64 
for normal substances ——— == — 
f- 27 
to a high degree of approximation. Accordingly I harbour the expec- 
tation that further investigation will make the exception for helium 
disappear. If, however, this small value of f is found confirmed on 
further investigation, helium would have to be called a very abnor- 
may be considered as valid at least 
mal substance. 
So the quantity a is determined from 7) and p; by the relations 
already given in my Thesis for the doctorate, at least to a high 
degree of approximation. 
In my Quasi-association I had arrived at this relation through the 
assumption that in the critical point two quantities would have the 
same values as follows from tbe assumption 6 = constant, viz. 
sr = 8 and (f—1)7* = 27. Then s’7* = 64 and after elimination of 
„2 
s 64 
r we get (he equation 7 oe But the equation obtained after 
elimination of 7 can be valid without sr and (f—1) 7? being constant. 
Thus eg. with sr=7,5 and (f-—1)r? = 23,34 the ‘same relation 
between s and / can be refound. So the question is now whether 
both relations (sr=8 and (/—1)r* — 27) may be considered as 
valid to a high degree of approximation. As vj could indeed be 
determined experimentally, but not 7 = en , | had arrived at the sup- 
position sr=8 and (/—1) 7°27, by assuming a value for r which 
could not be far from the correct one. 
I have tried to determine what would follow for different proper- 
ties of the quantities in the critical point if the two relations men- 
80* 
