W. Gibbs on the Hexatomic compounds of Cobalt. 298 
When the chloride of purpureocobalt is in excess, or when the 
two chlorides are mixed in the proper atomic proportions, 
another double salt separates in very beautiful violet-colored 
prismatic crystals, which, like the last mentioned salt, are but 
slightly soluble in cold water, but are much more soluble in 
boiling water, and crystallize from the solution on cooling. 
This salt has the formula 
Co,(NH,),,Cl,+4HgCl, 
as the following analyses show: 
0°7938 gr. gave 04735 gr. Hg,Cl,=50°65 per cent mercury. 
0°3970 gr. gave 0°3771 gr. silver =31'23 per cent chlorine. 
0°9752 gr. gave 0°9356 gr. silver —=31°42 per cent chlorine, 
1°3600 gr. gave 0°1024 gr. cobalt = 7°52 per cent cobalt. 
alculated. Found. 
reury, 4 50°4 50° 
Chlorine, 14 31°35 81°23 9 3:1°42 
Cobalt. 2 be 
4 * 
On Blomstrand’s view the formulas of the two mercury salts 
may be written : 
gCl, [ NH,—Cl 
| NH,—NH,-Cl=HgCl, | | NH,—NH,- Cl=HgCl, 
G,, | NH; -NH,—Cl=HgCl, gi | NH,—-NH,-Cl=HgCl, 
°21 NH? _N =Hecl, 2 NH,—NH,-Cl=HgCl, 
| NH,—-NH.—Cl=HgCl, —« | NH, -NH, —-Cl=HgCl, 
| NH,—Cl 
solution of HgCl,Na is added to one of the soluble sulphate _ 
ri 
