30 MATER i A MEDIC A AND THERAPEUTICS. 



Characters. A white deliquescent powder, of saline, 

 feebly acid taste. 



Dose. 20 toJJOjjr. 



d. Potassee AcetaSj. Acetate of Potash. KC 2 H 3 2 . 

 Source. Made by dissolving Carbonate of Potash in 



Acetic Acid, evaporating, and fusing the residue. K 2 C0 3 

 + 2(HC 2 H 3 2 ) = 2(KC 2 H 3 2 ) + H 2 4- CO 2 . 



Characters. White foliaceous satiny masses, very 

 deliquescent ; neutral. The peculiar appearance of this 

 salt is due to crystallisation after fusion. 



Impurities. The carbonate ; detected by being in- 

 soluble in spirit. Excess of acid ; giving acid reaction. 

 Metallic impurities. 



Dose. 10 to 60 gr. 



Potassce Acetas is used in preparing : 



T^ncturaJFerri AcetaJig. See Ferrum. 



e. Potassae Chloras. Chlorate of Potash. KC10 3 . 



Sotirce. Made by passing Chlorine gas into a mix- 

 ture of Carbonate of Potash and Slaked Lime (i.e. caustic 

 potash), boiling, evaporating, and separating the chloride 

 of potassium by re-crystallisation. 6KHO + 6C1 = 

 KC10 3 + 5KC1 + 3H 2 0. 



Characters. Colourless rhomboidal crystalline 

 plates, with a cool, sharp, saline taste. Explodes when 

 rubbed with sulphur. Soluble in 16 parts of cold water. 



Impurities. Chloride of calcium, and lime. 



Dose. 10 to 30 gr. 



Preparation. 

 Trochisci Potassse Chloratia, o gr. in each. 



_/. Potassa Soilphnrata. Sulphurated Potash. 



Source. Made by fusing together Carbonate of 

 Potash and Sublimed Sulphur. 



Characters. Solid greenish masses, liver-brown 

 when recently broken, alkaline and acrid to the taste ; a 

 mixture of sulphide, sulphate, sulphite, and hyposulphite. 



Dose. 3 to 8 gr. 



Preparation. 

 Unguentum Potassae Sulphuratae. 1 in 15J. 



2. Potassse Tartras Acida. Acid Tartrate of 

 Potash, Bitartrate of Potash, Cream of Tartar. KHC 4 H 4 6 . 

 |j Source. Prepared from argol, the deposit in wine-casks. 



