( 158 9 
{—= 33°25 
A P 
0 276 mM.) 
0.050 276 » 
0.080 276 > 
0.203 282 » 
0.295 204 » 
0.500 355 » 
0.588 412 » 
0.695 500 » 
0.898 657 » 
0.955 697 » 
1 fo. » 2) 
It is evident that we shall have to renounce either the relation 
ay. =V 4 or at least part of the simplifications which lead to 
the before-mentioned formulae of VAN DER Waars. The simplifica- 
tions are: the application 1s* of the equation of state in its simplest 
form, 284 of the wellknown equations for a, and bz, 3"¢ of the equation 
dz 
d= 
WH 
Tar These simplifications are certainly not all quite 
dx, 
correct, but it seems nevertheless not probable, that a more accurate 
formula would give such considerable correction-terms, that through 
Ae oy. 
them alone the strongly positive value of el ae be explained. 
eee 
For the present it seems therefore most advisable to give up the 
1) For chloroform we know only the determinations for vapour-tensions of REGNAULT. 
According to v. ZawrpzKt however, his values must be inaccurate, as he had no 
pure chloroform at his disposal. 
2) At 30° Ramsay and Youre found for ether 647.92; Barruur 648.21. At the 
same temperature our observations give 649 mm. So the deviations are not greater 
than our probable error. 
