362 C. H. Wing on certain Double Sulphates, 
The formula indicated is 12NH, €0,350,+3(€eS56,)-+-H, 8. 
VI cula’ 
se, 47°77 8°40 
€e 24°10 23°04 
€o 9°31 9°91 
NH, 16°10 17°14 
H,¢@ 2°07 151 
99°35 100°00 
I succeeded also in forming the analogous salt of lanthanum. 
Toa concentrated solution* of the sulphate, luteo-cobaltic sul- 
— was added, and the solution heated. The precipitate of a 
uff yellow color showed under the microscope crystals appa- 
rently of the hexagonal system with the edges so rounded as 
almost to conceal the hexagonal form. 
IX. 1:0648 grms. substance gave ‘3085 a@ and ‘2495 €oSO, 
a _ “ -9072 BaSO 
‘8918 “ «“ “ -9452H,O 
Assuming the atomic weight of this lanthanum to be 94, the 
probable formula is 12NH, €0,350,+-3(faS6,)+H, 0. 
Ix. culated. 
sé, 47°58 48°08 
Ea 24°76 23°54 
€o 8°92 9°85 
NH, 15°42 17°03 
H,0 3°01 1°50 
99°69 100-00 
Unsuccessful attempts were made to form double phosphates 
and chromates of cerium and luteo-cobalt. 
ee analogous to those formed with luteo-cobaltic sulphate. 
ey are, however, easily decomposed by water, sO much 80, 
| suce 
_ X was formed by adding, to an excess of hot strongly acid 
solution of roseo-cobaltic sulphate, a solution of ceroso-ceric Sw) 
phate; this yielded a crystalline orange-browr precipitate which 
* This solution contained also didymium and was obtained from the mother 
ulphate before described, by ‘‘ Watt's 
ic s 
d with chlorid of ammonium. is 
