166 
Applying then equations (14), (15) and (16) of Leiden Suppl. N°. 39a 
and substituting in equation (16) of Comm. N°. 65, we finally obtain : 
B= }n.4 20° | 1—1.0667 (hv)? + 0.1741 (Av)* —0.4738(hv)* + 0.6252 (Av)’... 
a 
— 2,4 — hv [1 + 1.0667 (he)? — 0.3641 (hv)! 40.2267 (hv)'...J} - « (5) 
§ 5. Hydrogen. Substituting for hydrogen = =0,0640 (Comm. N°. 65 
§ 4) we find: 
B=4n.4 xo*}1—0.1536 hv — 1.0667 (hv)? + 0.0108 (Av)? — 
— 0.4179 (hw)* + 0.5904 (hv)* —0.2360 (hv) + 
+ 0.1855 (hv)? — 0.1079 (he)? + 0.0593 (Av)?...3. « … . (6) 
This gives for the Joune-KrLvin point of inversion for small 
densities (comp. Leiden Suppl. N°. 39a § 4): 
OR ee OOB EE EEE 
TR 
From this we derive for B expressed in terms of — iig 
dE 
—l = as 
B = B,,{1—0.0778 tine — 0.2699 tinny + 0.01811 tinny — 
— 0.02675 tint) — 0.01901 tan — 0.00882 tans) + 
SHO. OOTTO fe 20 00042 tas 40000 Uden oe eo tae) 
0.6 0.160 | 0.246 
0.75 0.426 0.650 
! 0.655 1 
1.5 0.829 1.266 
2 0.895 1.366 
3 0.944 | 1.411 
4 0.963 | 1.470 
In this way we reach an accuracy of about 1°/, (of B, at 
T=0,6 Tinv(z=0)). The preceding table gives some of the calculated 
values. 
In fig. 1 these values have been plotted together with the 
