SODIUM. 35 



biliary stimulants. Potassa Tartras, Tartras Acida, and Acetas 

 the same, but more powerful diuretics; also saline purga- 

 tives. Potasses Sulphas chiefly purgative. Potasses Nitras 

 excreted unchanged in the urine ; is a double diuretic, and 

 probably in this way only a mild febrifuge. Potassa 

 Chloras excreted unchanged in all the secretions, inclu- 

 ding the saliva ; and is much used in inflamed, ulcerative, 

 and aphthous states of the mouth. The remaining salts of 

 potassium contain, in combination with the alkali, an element 

 or acid possessing such distinctly specific actions that the total 

 effect is but in a minor degree referable to the potash. Such 

 are the arsenite, bromide, iodide, and permanganate, and sul- 

 phurated potash. These will, therefore, be discussed under 

 the head of their other constituents. 



SODIUM. Na. 23. 



The following are the officinal salts and prepara- 

 tions of sodium, arranged according to their source : 



1. Sodae Carbonas. Carbonate of Soda. Na 2 C0 3 , 

 10H 2 0. 



Source. Made from the ashes of marine plants, or fromi 

 chloride of sodium by chemical decomposition. 



Characters, Transparent colourless laminar rhombic 

 crystals, efflorescent, with a harsh alkaline taste, and alkaline 

 reaction. 20 gr. neutralise 9'7 gr. of citric acid, or 10 gr. of 

 tartaric acid. 



Impurities. Sulphates and chlorides. 



Dose. 5 to 30 gr. 



From Soda Carbonas are made : 



a. Sodse Carbonas Exsiccata. Dried Carbonate of 

 Soda. Na 2 C0 3 . A dry white powder, made from Car- 

 bonate of Soda by drying. 53 gr. = 143 gr. of tha 

 crystallised salt. Dose, 3 



b Sodss Bicarbona.8. Bicarbonate of Soda. 

 NaHC0 3 . 



Source. Prepared from a mixture of the Carbonate j 

 and Dried Carbonate by passing a >d-, am of oarbonio( 

 acid gas through them; Na.,C0 3 + ILjO + C0 2 = 

 2(NaHC0 3 ). 



Characters. A white powder, or small opaque 

 irregular scales, of a not unpleasant saline taste. 20 

 gr. neutralise 16'7 gr. of ritrir acid, or 17'8 gr. of tar- 

 taric acid. 1 part soluble in 10 of \\ 



