555 
termed triple Prussiates, 
Experiment B. Experiment C. Mean of both. 
Sulphuretted chyazic acid 37.15 3^*5^ 3^*855 
Protoxide of copper 62.85 ^3.444 ^3145 
100.00 
100.00 
100.000 
Analysis of sulphuretted Chyazate of Barytes, 
A. Ten grains of this salt that had been previously dried 
at 212® and weighed immediately, were heated to 400° for half 
an hour without losing any weight. 
B. Another ten grains in the same state of dryness, dissolved 
in water and decomposed by sulphuric acid, gave of ignited 
sulphate of barytes 10.5 grains, which contain according to 
Berzelius 6.33 of barytes. 
C. Another ten grains in the same state, and also dissolved 
in water, were decomposed by muriate of protoxide of copper; 
they produced eight grains of sulphuretted chyazate of prot- 
oxide of copper, the acid contained in which, by my analysis 
of that salt, is 2.95 grains. 
The sulphuretted chyazate of barytes fully dried at 212° is 
therefore composed as follows. 
Experiment B. Experiment C. Mean of both. 
Sulphuretted chyazic acid 30.7 29.5 30.1 
Barytes - - 69.3 70.5 69.9 
100.0 100.0 100.0 
The soluble sulphuretted chyazates are excellent tests not 
only for indicating the presence of oxide of copper in a solu- 
tion, but also for shewing its quantity with great exactness, as 
