( Jas } 
Aa= (1 + aarvt) Aa, , aay = 0.0036618 
Ba CA 
[oT es BN i a nen. 
VA v iy po 
(Comm. N°. 71). Since the question is one of calculation of density 
at a given pressure the last equation is transformed to 
( (p 
PUA == Aa oe Boy ae tee Pra Lee 3 +, 
in whieh 
(p) B Gs A Zo a, 25 "—8A Ts, CG 
pee A Ol ee pe A dee 
A4 A AG A 
(cr Comm Ne: 925 lepe 1S ‘and! N°"109)p:-7). | 
In exactly the same way densities at ordinary temperatures may 
be obtained from the isotherms of Comm. N°. 78. These do not 
allow the proper evaluation of C4 in the equation given above; 
on the other hand as is shown in Comm. N°. 71 Amacat’s isotherms 
are uncertain as far as by is concerned. We therefore take the 
value of Cy from VII.1 and subsequently B4 from the isotherms 
of Comm. N°. 78. 
From VII.1 we get 
BA GA 
at Ove G — 0.82164 . 10-8 2D OS 
LEDE — 0.70050 . 10-3 Jha: LOSE 
20505, — 0.66747 . 107 2238 08 
and from the individual isotherms (Comm. N°. 7L p. 10): 
By Ca 
at OP, — 0.9295 . 10-3 Dade ey AO 
150 — 0.7828 . 10-8 2.1925 . 10-6 
values which do not differ much from those deduced from VII. 1. 
Limiting ourselves to the lowest pressures so that the term in C 
is at the most 10°/, of that in 4 we get from the isotherms of 
Comm. N°. 78 
Bu 
at Oe Cr — 1.02843 .10-3 
Me: —+ (86590. 10—-2 
AO — 0.87466 . 10-3, 
and these values are contained in the formula 
10°. B4 = — 1,02843 + 0,008942 t. 
AA, = 1,00105. 
This formula was also used for the calibration of the steel capillary 
