634

Mixtures.

PART ill.

" Take of prepared chalk, half an ounce •, refined sugar,three drachms; acacia gum, in powder, half an ounce (an ounce,Dub.); water, a pint. Mix, by trituration."

Potio Carbonatis Calcis. Edin. Chalk Potion.

" Take of prepared carbonate of lime (chalk), one ounce; re-fined sugar, half an ounce; mucilage of gum arabic, two ounces.Rub them together, and then gradually add of water, twopounds and a half; spirit of cinnamon, two ounces. Mixthem."

These are common and useful forms of giving chalk in aci-dity of the primae viae; and combined with opium or catechuin diarrhoea. The dose is from f^j. to f^ij. given every threeor four hours; or after every liquid evacuation.

MISTURA FERRI COMPOSITA. Lond.» CompoundMixture of Iron.

" Take of myrrh, in powder, a drachm; subcarbonate ofpotash, twenty-five grains ; rose-water, seven fluid ounces and ahalf; sulphate of iron, in powder, a scruple; spirit of nutmeg,half a fluid ounce ; refined sugar, a drachm. Rub together themyrrh, the subcarbonate of potash, and the sugar, andwhile triturating, add first the rose-water and the spirit ofnutmeg, and afterwards the sulphate of iron. Put the mix-ture immediately into a proper glass vessel, and keep it closelystopped."

In this mixture the sulphate of iron is decomposed by thesubcarbonate of potash forming, by the change of constitu-ents which takes place, sulphate of potash and subcarbonateof iron; the former of which is dissolved, while the latteris diffused through the mixture, and kept suspended by themyrrh, which forms a saponaceous compound with the excessof alkali. The iron is in the state of a suboxide ; and as itrapidly attracts oxygen in this state, and is converted into thered oxide, it is necessary to keep the mixture very well ex-cluded from the air.

Medical properties and uses. — This mixture, which is nearlythe same as the celebrated antihectic mixture of Dr. Griffith,is an useful tonic, in all cases in which preparations of iron areindicated, particularly in hysteria and chlorosis, and in phthi-sis, when no active inflammatory diathesis subsists. The doseis from f >y. to f^ij. given two or three times in a day.

MISTURA GUAIACI. Lond. Mixture of Guatac.

" Take of guaiac, a drachm and a half; refined sugar, twodrachms ; mucilage of acacia gum, two fluid drachms; cinna-

' This name is certainly improper ; but it is not easy to invent one which would bedescriptive of the compound, and yet be sufficiently concise: Mistura mlxarlonatisferri cum myrrha would have been less objectionable.