W. Gibbs on the Hexatomie compounds of Cobalt. 121 
Calculated, Found. 
Cobalt 2 118 23°18 23°18 23°24 
Chlorine 2 71 13°94 13°84 
Hydrogen 24 24 4°71 4°90 
Nitrogen 12 168 33°00 32°91 
xygen 8 128 25°17 peta 
509 100-00 
The corresponding bromide, Co,(NH,),(NO,),Br,, resembles 
the chloride so closely that no special description is necessary. 
Tn this salt, 
0°3944 gr. gave 0:2059 gr. CoSO,=19°87. 
The formula requires 19°73 per cent. 
_ Hyperiodide.—When a solution of iodine in potassic iodide 
is added to one of the nitrate of this series, a magnificent crys- 
talline cinnabar-red compound is precipitated, which may be 
without decomposition. For analysis, the salt was dried in 
pleno over sulphuric acid. The crystals are small scales of 
05748 gr. gave 0°1494 gr. Co.SO,= 9°87 pr. ct. cobalt. 
94705 gr. gave 0°2550 gr, silver =63°70 “ iodine. 
. mm 
63 
03942 gr, gave 49 ¢.¢, nitrogen at 14°5° C, and 736°8 =14°10 per 
cent nitrogen. 
* Calculated. Found. 
Cobalt 2 118 9°83 9°87 
Iodine 762 63°50 63°70 
Nitrogen 2 168 14-00 14°10 
Hydrogen 24 24 2-00 hig 
xygen 128 10°67 em 
1200 100°00 
of we consider iodine as triatomie in this salt its constitu- 
tional formula may be more simply represented by the ex- 
pression : 
NH,=I-NO, 
NH,=I-NO 
Co H,=—NH,~ 
’ NH,=NH,—I 
NH,=I-NO, 
