1889.] On Salts of a Base containing Chromium and Urea. 331 



The Ferricyanide. 



This compound is precipitated in olive-green needles on the addi- 

 tion of potassium ferricyanide to a soluble salt of the base. The salt 

 is sparingly soluble in cold, more readily in hot water, from which it 

 crystallises in long prismatic crystals, having the composition 

 (CON 2 H 4 ) 12 Cr 2 2FeC 6 N 6 8H 2 0. 



The following results were obtained on analysis : 



1. 0-3501 gram gave in vacuo 0-0351 gram H 2 0. 



2. 0-3501 on ignition 0'0790 gram O 2 3 + Fe 2 3 . 



3. 0-3418 at 100 C. 0*0343 gram H 2 0. 



4. 0'3418 on ignition 0-0777 gram O 2 3 +Fe 3 3 . 



The Ferrocyanide. 



This compound is precipitated in green needles, when a soluble 

 ferrocyanide is mixed with a soluble salt of the base. The crystals 

 are very sparingly soluble in water, either hot or cold, and insoluble 

 in the usual organic solvents. 



The examination of the substance led to the formula 



{(C01Sr 2 H 4 ) 12 Cr 2 } 2 3FeC 6 N 6 17H 2 



being assigned to it. 



The following results were obtained on analysis : 



1. 0-2396 gram salt gave in vacuo 0'0279 gram H 2 0. 



2. 0-2396 on ignition 0'0504 gram O 2 3 + Fe 2 8 . 



3. 0-4387 in vacuo 0'0524 gram H 2 0. 

 4.0-4387 on ignition 0-094 gram Cr 3 3 + Fe 2 3 . 



VOL. XLV. 



