^otassii Nitras. (Nitre, Saltpetre.) Dose, 5-20 grs.; 3-12 

 dgms. 



KNOs. White crystalline masses, colourless with a cool, saline taste. 

 Soluble 1 in 4 of cold, 1 in X f hot water, sparingly soluble in alcohol. 



^otassii Permanganas. Dose, 1-3 grs.; X~2 dgms. 



Dark purple slender iridescent crystals, with sweet astringent taste. 

 Soluble 1 in 20 of cold, 1 in 3 of hot water. 



3 Liquor Potassii Permanganatis. Dose, 2-4 fl. dr.; 8-16 c.c. 

 1; Water, 100. 



3 Potassii Sulphas. Dose, 10-40 grs.; ^-2>^ gms. 



Colourless, hard crystals. Soluble 1 in 10 of cold, 1 in 4 of hot water, 

 insoluble in alcohol. 



3 Potassii Tartras. Dose, 30-240 grs. ; 2-16 gms. 



Normal potassium tartrate, (CHOH);;.(COOK) 2 , H 2 O. Small, colourless 

 crystals. Soluble 1 in 0.6 of water, insoluble in alcohol. 



Potassii Tartras Acidus. (Bitartrate, Purified Cream of Tar- 

 tar.) Dose, 20-60 grs.; l#-4 gms. 



A white gritty powder, or fragments of cakes crystallised on one surface, 

 with an acid taste. Soluble 1 in 200 of water, insoluble in alcohol. 



PRUNI VIRGINIANS CORTEX. The bark of Prunus serotina. In 

 curved pieces or irregular fragments about 1/12 inch thick. Taste as- 

 tringent aromatic, and bitter; when macerated an odour of bitter almonds, 

 due to the formation of hydrocyanic acid from the amygdalin under the 

 action of the ferment, emulsin. 



x Syrupus Pruni Virginianse. Dose, 30-60 min.; 2-4 c.c. 

 A macerate and percolate of the bark in water to which sugar and glycerin 

 are added. 



3 Tinctura Pruni Virginianae. Dose, 30-60 min. ; 2-4 c.c. 

 20; Alcohol, 62.5; Water, 37.5: by maceration. 



Prunum. Prunes. The dried ripe fruit of Prunus domestica. 

 Contained in Confectio Sennae. 



Pterocarpi Lignum. Red Sanders Wood. (Red Sandal Wood.) 

 The heart wood of Pterocarpus santalinus. Usually imported in logs. 

 In chips it varies in colour from blood-red with lighter zones to a very dark 

 brown; a slight astringent taste and a faint odour when warmed. The 

 colouring matter is soluble in alcohol, and to a very slight extent in water. 

 Used in the Compound Tincture of Lavender. 



PUL VERES. (The following, with a dose of 1-4 grs. Elaterini Comp.; 

 dose 1-5 grs. Hydrargyrum cum Creta; with dose, 3-6 grs. Antimonialis; 

 dose, 2-10 grs. Opii Comp.; dose 5-15 grs. Ipecacuanhas Comp.; dose, 



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