POLYPUS. See NASAL CAVITIES, EXTERNAL EAR, UTERUS, etc.
POTASSIUM.—Potassium, or kalium, is a white metal, discovered by Sir Hum phry Davy in 1807, having the consist ence of wax; the fresh-cut surface has a silvery lustre, rapidly changing by oxidation to bluish or gray. Its affinity for oxygen is very strong. Exposed to the air, it oxidizes instantly. Thrown upon water, it takes fire spontaneously, and burns with a beautiful purple flame, yielding an alkaline solution of potassa, or potassium hydrate. Potassium hy drate, or potassa, is a strong alkaline base, very deliquescent, and soluble in half its weight of water. From this base the medicinal preparations are made. The metal is never used in medicine. Some of the preparations are strongly alkaline and have a high diffusive power; this group contains potassa, potassa with lime, potassium carbonate and bicarbonate. A second series is neutral in reaction and alkaligenous (become alkaline by decom position, the vegetable acid being re placed by carbonic acid, and an alkaline carbonate being formed); this group con tains potassium acetate and citrate, of high diffusive power, and potassium and sodium tartrate and potassium tartrate, of low diffusive power. A third series is permanently neutral or acid; this group contains potassium bitartrate and sul phate, of low diffusive power, and the nitrate, chlorate, bichromate, and iodide, of high diffusive power.
Upon a therapeutic basis, another use ful classification may be made.
Caustics: potassa, potassa with lime, and potassium bichromate.
Purgatives: potassium bitartrate (4 to S drachms), potassium and sodium tar trate to 1 ounce), the acetate (2 to 4 drachms), and the sulphate to 4 drachms).
Systemic antacids: the carbonate (10 to 30 grains), the bicarbonate (20 to 60 grains), the solution of the citrate (1 to S drachms), the acetate to drachms), and the tartrate of potassa and soda (20 to 40 grains).
Diuretics: the bitartrate (1 to 2 drachms), the tartrate of potassa and soda (V, to 1 drachm), the acetate to 1 drachm), the citrate to 1 drachm), the carbonates to 1 drachm), the nitrate to drachm), and the iodide to 1 drachm).
Febrifuges: the solution of the citrate (1 to 8 drachms), the citrate (20 to 30 grains), and the nitrate (10 to 30 grains).
Alkaline lotions: solutions of the car bonate and the bicarbonate (1 to 2 drachms to 1 pint).
Anti-emetic: the citrate of potassa to 1 drachm).
Preparations and Doses.—Potassa, U. S. P. (potassium hydrate, or hydroxide; caustic potash).
Liquor potassw, U. S. P. (solution of potassa, 5 per cent.), 10 to 30 minims.
Potassa cum calce, U. S. P. (Vienna paste or caustic—potassa, 50 per cent.; lime, 50 per cent.).
Potassa sulphurata, U. S. P. (sul phurated potassa; liver of sulphur), to 5 grains. (See SULPHUR.) Potassii acetas, U. S. P. (acetate of potash), 10 to 60 grains.
Potassii bicarbonas, U. S. P. (bicar bonate of potash), 10 to 60 grains.
Potassii bichromas, U. S. P. (bichro mate of potash), to 1 grain.
Potassii bitartras, U. S. P. (bitartrate of potash; cream of tartar), 1 to 8 drachms.
Pulvis jalapw compositus, U. S. P. (potassium bitartrate, 65 per cent.; jalap, 35 per cent.), V, to 1 drachm. (See JALAP.) Potassii bromidum, U. S. P. (bromide of potash), 10 to 60 grains. (See BRO MINE.) Potassii carbonas, U. S. P. (carbonate of potash), 10 to 30 grains.
Potassii chloras, U. S. P. (chlorate of potash), 5 to 10 grains.
Trochisci potassii chloratis, U. S. P. (chlorate of potash, 5 grains), 1 to 5 troches.
Potassii citras, U. S. P. (citrate of potash), 15 to 60 grains.
Liquor potassii citratis, U. S. P. (solu tion of citrate of potash), 1 to S drachms.
Potassii citras effervescens, U. S. P. (effervescent citrate of potash), 30 to 90 grains.
Potassii cyanidum, U. S. P. (cyanide of potash, 90 per cent.), to grain.
Potassii et sodii tartras, U. S. P. (tar trate of potash and soda, Rochelle salt), 1 to S drachms.