318 
If we take A. and J.’s value at 15° C. as basis for the calcula- 
tion, A: D would become = 21,22, v= 94,70. 10, so that we 
find for 6, with 
f = 3,068 [1—0,6054 x 0,0973} — 3,068 (1 —0,0589) = 2,887 
the value 6, == 273,4.10 5, though the value 305. 10-°, which is 
more than 10°/, higher, was expected. Hither the critical tempera- 
ture, and because of this also y, has been estimated too low, or 
the density has been assumed too high. But the latter is not very 
probable in view of the still greater value at the melting point. 
In connection with the values of 77, and p; we still draw attention 
to a series of vapour pressure determinations of GrreNwoop (1910). If 
Va, is really =35,65 .10-?, as we found above, and br =305 .10~?, pr 
— 444,3 atm., loy™ pe = 2.6477 would follow from pj = ‘/,,4 an: Oy’. 
We find the vapour pressure factor /’,, of VAN DER Waats’s formula 
log’ (pr: Pp) = F,, (44/7-—1) therefore from 
2,648 - log p 
eae Nee 
From: 
ieee Bol 1583° 1693° 2013° 2223° 2333 als: 
p = 102 257 mm. ] 6,3 AAE 16,5» atm: 
would then follow: 
AE TER NE? eN Ae NL 
The rise of the value of / need not astonish us, when we think 
that the state of nothing but simple molecules has not been reached. from 
the outset, and that at 1500° abs. molecules Bi, (or 47,) can very well 
be present. The attraction is then smaller than the final value a; — 35,6. 
10-2, so that also 7; will be smaller than 2960° abs. And this is ac- 
companied with a decrease of the value of /’. But yet the increase 
seems somewhat too great to us, because according to the formula 
Fy, = 8y the value of # at the critical point wiil have to be about 
— 12.3, ie. F,, = 5,33. And with 7; = 2960° abs. the value of # 
would already be —5,3 at 2333°, and evidently be still increasing. 
If we assume 77, — 3000° abs., we should find the following 
values of F’: 
FF, = 3,40 3,49 3,44 3,78 4,54 5,02, 
which increase less rapidly at the highest temperatures, and remain 
below 5,35. 
If 7), — 3000° abs., also a, would become slightly greater, viz. 
(B is now — 0,909) a, = 1290. 10 -*, which would render War = 
— 35,92. 10 °. The value 2y would become 3,081 instead of 3,07, on 
