NEITHER POTASH NOR AMMONIA. 445 



1 atom carbonate of lime 6-25 



1 atom carbonate of magnesia 5-25 



11-5 



I find the magnesian limestone of Sunderland is 

 composed of these proportions. 



(.) Rhombspar, on the other hand, as is ob- 

 vious from the analyses of Klaproth, is a corh- 

 pound of 



2 atoms carbonate of lime 1 2-5 



1 atom carbonate of magnesia 5-25 



17-75 



3. Boro-tartrate of potash-and-soda.* This 

 is the well known salt which has a place in sev- potash a 

 eral of the foreign pharmacopoeias under the 50 

 name of cremor tartari solubihs. It is made by 

 dissolving 1 part of borax in 8 parts of boiling 

 water, and adding to the solution as much bi- 

 tartrate of potash as it will dissolve. The solu- 

 tion is filtered and evaporated to dryness in a 

 gentle heat. The compound salt thus prepared, 

 is employed in dropsy and amenorrhgea, and pos- 

 sesses nearly the same virtues as bitartrate of 

 potash. Its taste is cooling, bitter, and much 

 more disagreeable than that of cream of tartar, 



* Though this salt contains potash, I have thought it better to place it 

 here than among the compound salts of potash, for reasons that will be 

 easily perceived by the attentive reader. 



