SODiE

401

acid, and forty-nine of water. It is soluble in cold, but one-thirdmore so in boiling water.

Incompatible with acids, the salts of ammonia, and the earths, andwith potass.

Medicinally it is detergent when used with honey or with water as agargle in aphthous sore-throat, hyper-salivation, &c. It has latelybeen said to be a powerful remedy when dissolved in water for can-cerous sores of the lips, &c. It is also diuretic and emmenagogue indoses of gr. x to 3SS.Son* Subcakbonas. L. E. D. P. Subcarbonate of Soda. Take ibj ofimpure soda reduced to powder, Oiv of distilled water ,• boil the sodain the water for half an hour, and strain the solution ; evaporate totwo pints, and set it aside that crystals may form: throw away thesolution that remains.

Chemically the impurities of the barilla are got rid of by dissolving it,and then crystallizing. It contains 29-5 parts of soda, 20'7 of car-bonic acid, and 50 of water of crystallization. It ought to be calleda carbonate rather than a subcarbonate. (Brande.) By exposureto dry air it becomes opaque and loses a considerable quantity of itswater of crystallization, but has not been observed anhydrous.CGay-Lussac.)

Adulterated with muriate and sulphate of soda, and oxide ofiron. The two first are detected as in the preceding article,and the last is seen at once in the reddish-brown colour of thecrystals.

Incompatible with acids and acidulous salts, sub-borate of soda, muriateand acetate of ammonia; the sulphates of alum, copper, iron, mag-nesia, and zinc, lime water, tartarized antimony and iron, and thesalts of mercury.

7'Iedicinalh) it has no smell, but an alkaline though not an acrid taste.It is an excellent antacid and deobstruent. It is not so harsh andnauseous as the subcarbonate of potass, and agrees better when longcontinued. It is given in doses of gr. x to 5j twice or thrice a dayin solution in the almond mixture, or in form of an electuary withan equal quantity of powdered bark mixed with mucilage, forscrofula, gravel, &c. In too large doses (5ij to 5iij) it producesmilky urine and a deposit of white sand.

Enters into Soda? Subcarb. Exsicc. L. D. Sodse Carbon. L.Sod^e Subcakbonas Exsiccata. L. Dried Subcarbonate of Soda.Carbonas sodw siccatum. D. Take ftj of subcarbonate of soda ;expose it to a boiling heat in a clean iron vessel, and stir it constantlywith an iron rod, till it become perfectly dry, and then reduce it topowder.

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