526 
maximum value is given by the point of intersection of the two 
lines, which are determined by the constants C” and A’, in the first 
disturbed paramagnetic state (we shall designate that state normal 
in which the Curtm law holds), and by the constants C’’ and A’’ 
in the second disturbed paramagnetic state. The temperature of the 
maximum therefore alters with the quantity of moisture contained 
in the salt. It lies just above the boiling point of hydrogen, so that 
a new arrangement of the experiment is necessary before the correctness 
of this deduction can be tested and at the same time an investigation 
made as to whether the formula given holds good up to the maximum 
or not. That this is probably so is corroborated by the fact that on 
cooling ferrous sulphate I down to 20° K. x would increase continuously 
until it began to fluctuate about its mean final value, while on 
cooling ferrous sulphate III x clearly overstepped its maximum value 
before the temperature of the bath was reached, just as is to be 
expected from the diagram. 
§ 4. Anhydrous ferric sulphate down to — 208°C. Anhydrous 
ferric sulphate was also investigated at the same time as the ferrous 
sulphate to ascertain any possible influence of the valency of the 
iron atom, and to see if x for ferric sulphate also reached a maximum 
value. Down to the temperatures available with liquid nitrogen and 
in that temperature region we found perfectly regular behaviour 
corresponding to what we have termed the first disturbed paramag- 
netic state. We found: 
TABLE III. 
Anhydrous ferric sulphate 1 above — 208° C.; ,’=31. 
cr a es 
6 
i 4.10 | =C’. 106 Limits of A Bath 
289°.8 K 93.3 | 17100 9000—15000 room atmosphere 
169 .6 85.6 | 17170 7000 — 17000 liquid ethylene 
71 .4 157-2 | 117040 | 
70.5 167.3 | 16980 | 14000-17000 liquid nitrogen 
| 64.9 | 1771 | — 16980 | | | 
| | 
| | 
Valeney, which plays such an important part in solutions, has 
here but a very slight influence down to and at nitrogen temperatures ; 
