(AM) 
presently subject a probable relation between the values of some 
critical quantities to an investigation. 
Let us now proceed to derive a value for R7;. We do this by 
the aid of the value of what is often called “critical coefficient”, 
which is also to be derived from the determinations of SYDNEY YOUNG 
and given by himself; viz. the quantity s from the relation: 
RE, 
PRU 
The uncertainty which exists in this quantity s is for the greater 
part the consequence of the uncertainty in the value of vz. In most 
cases vj was not directly determined, but calculated from the course 
of the value of liquid- and vapour volume at temperatures near 7’. 
This can be done with the aid of the law of the rectilinear diameter, 
‘ B dp dp : 8 
or by applying the criterion ee For RT, we ‘ind now 
c t a kr 
the value: 
EL UI) 
ee a 
by (fr = Ur? 
Eliminating 6, and r, we find from equations (f) and (44): 
(Tz)? Se 
——= 
Pk Fak 
(ITT) 
In my Quasi-association (These Proc. June 1910) I pronounced 
the expectation that at least approximately the factor of a, viz. 
2 
GAG would always have the same value for all normal substances, 
ae 5 
whatever might be the law of variability for the quantity 5. I have 
since been strengthened in this opinion by the investigation of the 
5 
S 5 ate 
value of ra for all normal substances, for which the quantities s 
and f have been determined experimentally. 
2 
s 4 
If 6 does not vary with v, the value of aay is equal to a and 
2 
so we have to examine if is always found equal to this value. 
In order to investigate the correctness or incorrectness of this 
relation as impartially as possible, I have taken the values for s 
and f which are given by Kuxrnen (Die Zustandsgleichung ete.), and 
then calculated s from: 
WA OE iy 
— Seg 
