SULPHURETS. 



phur. The five following sulphurets of potassium 

 seem to be established by these experiments. 



POTASSU'M. SULPHUR. 



1 . Sulphuret of potassium 1 atom -}- 1 atom 



2. Bisulphuret . . 1 atom -[- 2 atoms 



3. Trisulphuret . . 1 atom -|. 3 atoms 



4. Quadrosulphuret . 1 atom -f- 4 atoms 



5. Quintosulphuret . 1 atom -f 5 atoms 



Berzelius is also of opinion that there exist two 

 others composed of 



POTASSU'M. SVLPHLR. 



1. 1 atom + 3J atoms 



2. 1 atom + 4 atoms 



But though he formed substances containing the 

 ingredients nearly in these proportions, it is 

 more likely that they were mixtures. For we 

 do not in other cases find sulphur entering into 

 combination in such extraordinary proportions. 



2. Sulphurets of sodium. > _ 



o II ^T.I-- f Though these sul- 



3. Sulphurets of lithium. 3 



phurets have not been particularly examined, we 

 may conclude, from analogy, that they are simi- 

 lar to those of potassium. The protosulphuret of 

 sodium was made by Berthier, and found very 

 similar to the protosulphuret of potassium.* 



4. Sulphuret of calcium was formed by Ber- Calcium, 

 zelitis, by passing a current of sulphuretted hy- 



* Ann. de Chim. et de Phj*. XXII. 225. 



