SULPHATES OF SODA AND POTASSA. 53 



withdrawn by combination with the atmospheric oxygen, to form 

 water and produce animal heat ; a proposition, however, which ad- 

 mits of doubt. The salt leaves the body in the urine, and a portion 

 is also decomposed in the lungs, by the pneumic acid, into the pneu- 

 mate of soda. 



The bicarbonate of soda exists nowhere else than in the blood, and 

 there its existence is very probable, rather than demonstrated. It 

 is formed by the action of the carbonic acid in the blood upon the 

 carbonate of soda. Its function is too nearly identical with that of 

 the latter salt to need further notice here. 



7. Carbonate (and Bicarbonate) of Potassa. (KOC0 2 .) 

 The latter of these two salts is found in the urine of the herbivora, 

 but not in the human body at all. 



The carbonate of potassa exists in the blood of the herbivora, and 

 of man and the dog, when they consume vegetable food. It does 

 not, however, in the former, equal more than one-third or one-half 

 of the carbonate of soda. It is formed, like the latter salt, from the 

 malate, citrate, tartrate, lactate, &c., of potassa. Its function appears 

 to be very similar to that of carbonate of soda. 



8. Sulphate of Soda. (ISTaOSOg+lOHO.) 



This principle exists in very small quantity in the body, but in 

 almost every part and fluid, except the milk, bile, and gastric fluid. 

 It may be found in milk when administered medicinally. Poggiale 

 found 0.44 in 1,000 of human blood. It everywhere exists in a 

 fluid state, dissolved in water, and conduces to preserve the elasticity 

 of the blood-corpuscles, and to dissolve and keep in a liquid state 

 the fibrin of the blood. It is derived, probably, from food and 

 drink, and is evacuated in the urine. 



This sulphate, and that of potassa, increase in the urine in in- 

 flammatory diseases, while both diminish in chlorosis and chronic 

 maladies. 



9. Sulphate of Potassa and of Lime. (KOS0 3 and CaOS0 3 .) 

 The first of these is found wherever the sulphate of soda is, they 

 being both dissolved in water, and mixed. Simon found 3 parts in 

 1,000 of urine. Its functions appear to be like those of the pre- 

 ceding salt. 



The sulphate of lime is said to exist in the feces, in blood, and in 



