( 130 ) 
and 
Aao =1—(Bao + Cao + Dao + Hao + Fao). « « (5) 
eee 
We put as condition = + 0.0036625¢1) (where Ao=1) or in 
0 
other words we assume that formula (I) would show that at infinite 
volume the ideal gaseous state would exist. Hence follows with (3) 
and (1) 
Aap = Ar Asp = AA (1 + 0.0086625 E) |. DR 
The calculations were begun with preliminary approximations ; 
at the second approximation we worked with 
| Carbon dioxide 
Oxygen. | Nitrogen. | Hydrogen. 
4 = | 1.00706 | 1.06092 | 1.00038 | 0.99932 
The co-efficients By, Ca, Da, Ka, Fa, for each isotherm were now 
found to first approximation by solving the 5 equations following 
from 5 well-chosen observations, and then by successive calculation 
of differences without using least squares, were corrected as much 
as possible. The results obtained in this way individually for all the 
isothermals investigated are combined in the following table. 
The first column gives the substance and the temperature, for 
which AMAGAT has measured the isothermal. The second column 
indicates the solution for the five co-efficients, which gave the 
best agreement with this isothermal. Co-efficients which had to 
be assumed in those cases where the range of densities was not 
sufficient to determine 5 co-efficients individually are placed in 
brackets; this was the case with the higher temperatures for hydrogen, 
nitrogen, oxygen, where the pressures do not reach 3000 atm. as with 
the lower temperatures, but go only up to 1000 atm., and with tem- 
peratures below the critical temperature of carbon dioxide where 
the labile region occasions a similar uncertainty. 
1) In comparing with Comm. N°. 60 on the co-efficient of pressure variation of hydrogen 
it must be remembered that the calculations were begun before that communication. 
