Text-book of medical and pharmaceutical chemistry / by Elias H. Bartley.

  • Bartley, Elias Hudson, 1849-1937.
Date:
1898
Catalogue details

Licence: Public Domain Mark

Credit: Text-book of medical and pharmaceutical chemistry / by Elias H. Bartley. Source: Wellcome Collection.

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    6th. Acid waters, those containing free mineral acids, such as hydrochloric or sulphuric acid. 7th. Thermal waters, or such as come to the surface at a tempera- ture above that of 200 C. (68° F.). Some of these springs contain so little mineral matter as to be of no importance; the only value, if any, being in the temperature. They are used principally for baths. Official Forms.—Aqua. Natural water in the purest attainable state (U. S. P.). Natural water, the purest that can be obtained, cleared, if necessary, by filtration (Br.). Aqua destillata. Take of water 1000 vols.; distil 100 vols., reject, then distil 800 vols. (U. S. P.) The transparency or color of distilled water should not be affected by lime-water; nor by H2S, BaCl2, AgN03, or (NH4)2- C204, etc. The aquae of the U. S. P., or medicated waters, are solu- tions of a gaseous or volatile body in water, as aqua ammoniae, aqua chlori. A liquor is a solution of a fixed or solid body, as liquor ferri nitratis ; liquor plumbi subacetatis. A decoction is a solution made with boiling water, usually of a vegetable product. An infusion is a solution formed by subjecting the body for a short time to either cold or warm water. Maceration is the long-con- tinued action of water at the ordinary temperature. Digestion is the same with hot but not boiling water. Lixiviation or leaching is the process of pouring water through a porous mass of any substance, for the purpose of dissolving out soluble matters. Physiological Use.—Water exists in all the tissues of the body and in all foods and drinks. A healthy adult takes, on an average, about 2.5 liters of water in twenty-four hours; and loses by the skin, lungs, kidneys, and feces a little more than this; the excess coming from the oxidation of the hydrogen of the food and tissues. Water constitutes from sixty-five to seventy per cent, of the whole body, being in slightly larger proportion in the young than in the adult body. The water in the tissues serves as a solvent for the various proximate principles intended as nourishment for the tissues, or com- ing from their waste and intended for excretion. The evaporation from the skin serves to carry off the superfluous heat of the body. Hydrogen Dioxide, Hydrogen Peroxide, H202, Aqua Hy- drogenii Dioxidi (U. S. P.).—The simplest way of preparing a diluted solution of H202 is to pass a stream of C02 through water con- taining barium peroxide, Ba02, in suspension. Ba02 + C02 + H20 = BaC03 + H202. The insoluble barium carbonate may be separated by filtration, best