358 C. H. Wing on certain Double Sulphates. 
As the mode of preparation was that employed by Wolf, I 
have used the factor deduced from the mean of his analyses. 
I, 12885 grms of substance gave 1707 H, © and ‘6732 €e,0,= 
: 6400 €eO. 
II. 1:4090 grms. “ “ “ 1857 H,6 and °7372€e,0,= 
"7009 €eO. 
These results give the following percentages, to which I have, 
for the sake of comparison, appended those obtained by Wolf 
from his purest cerous sulphate. 
= IL Wolf. 
€ed 57°28 57°31 57°294 57°310 
3 42°72 42°69 42°706 42°690 
equivalent corresponding 45°64 45°69 45°66 45°69 
Taking the mean of these 45°67 as the true equivalent of ce- 
rium or 91°34 as the atomic weight and the formula 
3(€e,$O,)-+-5H, 0 
we have : 
i. é Wolf. Calculated. 
€e ae ee 42°08 
so TS Seige gee sable ipsa 44-17 
HO 13°24 1818 13318 12803 13°80 
the results obtained we can assume the cerium used in 
2 
in the crucible by means of aqua-regia and a few drops of st d 
hurie acid, was heated in the “radiator” until sulphune e* 
fumes ceased to be evolved, afterwards over the naked flame, 1° 
: peed moments, to low redness. e crucible was then allow 
f 
