(589 ) 
towards the critical state with a parabola of the second degree. In 
the very accurate determinations of density by SypNey Young, to 
which no corrections by interpolation have been applied and for 
which I have computed a formula of the same form as the one 
mentioned above viz. 
21 — Ovo = 0,11058 70,8434 
the agreement between observation and calculation appears to exist 
even at the highest temperatures (r = 0°,4). 
A log (ot — @v) ie RD en 1°,8 and 0°,8 a 0,344 
A log t ¢ = 0°68 and 0°,4 stall 0,337 
while, according to the law of the corresponding states we might 
predict already at r= 1°,5 a distinct increase from the above-men- 
tioned deviation in the case of the interpolation-curve of carbon 
dioxide. 
Therefore for the time being no experimental proofs can be given for 
the supposition, that up to the immediate neighbourhood of the 
critical state Qt — gy = A(1l — m)°5484 would not hold instead of 
the theoretical formula @7 — ey = A (1 — m)?. 
The table given here shows that my formula gives precisely the 
difference in density till about s= 60°. With lower temperatures 
the agreement diminishes. 
Be Ist It WAT. 
T (@1—Q») observ. _(Q7—Q)) calculat. 
0,4 0,0810 0,0807 
0,8 0,1023 0,1024 
1,8 0,1351 0,1353 
2,8 0,1567 0,1575 
4,8 0,1889 0,1895 
7,8 0,2240 0,2239 
11,8 0,2591 0,2581 
17,8 0,2982 0.2972 
27,8 0,3477 0,3464 
37,8 0,3862 0,3849 
47,8 0,4169 0,4173 
57,8 0,4443 0,4454 
67,8 0,4680 0,4705 
2. The relation deduced by VAN DER WAALS between the surface- 
tension o and the reduced temperature m 
