292 
substances, where b'‚ approaches '/, and r approaches 2, RT, becomes 
ag 8 a, 
28 bo 
We will now first substitute the found value of RT, in (4), in 
order to determine the value of @/,, at the critical point. If we 
write for brevity: 
a—(ltae)(l—b')A=A; (2-2) a—a(l—2)A=B 
(2—z) (1+ 2) (1—6) — (le) = 2 — (2—2) (142) b' = NY" 
we get, after substitution of 
; both known expressions. 
AB 
a Lee Oe he oe . pet (26) 
in 
(Z)= a (lr) RTv aA 
the equation 
Se (1—z2) AB: N 
(= tvb (2—a) a A + (2—2) AB: Ne (la) A?) 
In this (2—«)« A — a (l—e) A? = BA, hence also 
(F __ # (1l—a) A __#(l—a)A 
== bb NASA) oe eee 
because NA + (2—r) A is evidently = B. Hence we have now for 
dx 
(=) at the critical point the exceedingly simple expression 
t 
(= )= w(l1—a#)A alle) a—(1+e)(1—6) 4 
dv ede Ben v—be (2—a#) a—a (l—x) | 6) 
in which 2, 6’, a, and A all refer to Te. 
It is self-evident that it is unnecessary to derive an expression 
for p., as it follows immediately from the equation of state after 
substitution of the obtained value of RT. (Compare the first paper). 
§12. The Second Differential Quotient (2 and the Value 
OL == bee. 
As we observed already above, we cannot determine the final 
expression for RT, until also v, has been expressed in 6,. But for 
this the knowledge of the second differential quotient is required, 
which must again be put = 0 at the critical point. 
