DE. ANDREWS ON THE GASEOUS STATE OF MATTER. 
445 
volume a c is equal to ab P h and let the temperature be now if; the point c on the 
I"’” 1 ^ the h ° mol °8 ue of the P° int b on the isothermal t If the gas from 
fh * w T lmi " Slled m volume as a Perfect gas, c would have been a point on the iso- 
th® Z T\ “ homoIo S ue c ’ of the Point * on the isothermal t, is a point on 
he isothermal t at which the action of the internal forces, in reducing the volume of the 
0 s when the external pressure is increased from* to/, is exactly counterbalanced by 
the action of the expansive forces in heating the gas from t to t. 
voluLT! ° f e r ati ° DS (A) and (B) ’ if We kn ° W the rela ti° ns of pressure and 
&aS a any 0ne tem P ei 'ature, we can, by the observation of a homologue at 
ZnetTu r P Tb in ZZ® the VOl " me corres P“ di "S to all pressures at the second 
be discove d f US he W f h ° le reIatl0ns of TOlume and pressure in the case of a gas can 
minaZ f 1 \ °! P 1 ™^ ° bselTatioD8 at ° n e fixed temperature, and the deter- 
mmation of a single homologue at each of the other temperatures. 
e f ave ” t0 “imre into the relations between the pressure and volume in the 
case of a gas a t a constant temperature; in other words, to discover, if possible, the 
chaiacter of the primary curve from which, as we have seen, by means of the homologues 
a 3? °f 1 ‘tTZtv may be taCed - F ° r thiS PUr P° Se 
™ Z fj ~ P fr °“ T* XIV -’ XV - “d XVL, and thence calculate the values of 
( P) a s given m the fourth column of the following tables. • 
Table XXII. — Values of e(l — p ) at 6 0, 5. 
1 * 
£. 
f. 
1 1-p. 
8(1 ~ P ). 
12-01 
1 
12-95 
6*5 
0-0726 
1 0-00561 
1 3-22 
1 
14-37 
6-5 
1 0-0800 
0-00557 
14-68 
1 
IHs 
6-5 
0-0899 
0-00557 
17-09 
Ul2 
6-5 
0-1062 
| 0-00555 
20-10 
1 
23-03 
6-5 
0-1272 
0-00552 
22-26 
1 
2f96 
6-5 
0-1425 
0-00549 
24-81 
1 
29-62 
6-5 
0-1624 
0-00549 
27-69 
1 
3703 
6-5 
0-1863 
0-00547 
31-06 
1 
39^59 
6-5 
0-2155 
0-00544 j 
3 q 
mdccclxxvi. 
