RHUBARB

The root of the Rheum palmatum, and perhaps some other species, cultivated in China for the supply of the drug market. The varieties of rhubarb known in commerce under the names of Ru ian, Turkey, and Indian rhubarb, are all derived from one source; but the select pieces are sold under the name of Ru ian and Turkey rhubarb, and those of somewhat inferior quality as East Indian. To judge of the quality of rhubarb, it should be cut or broken; when good it is of a mottled reddish or brownish red colour; that which is very pale or very dark coloured, and either so soft as to be spongy, or hard and stony in texture, is bad. Rhubarb is a valuable article of the materia medic a, being an aperient, and at the same time a tonic and astringent. The average dose of powdered rhubarb is twenty grains, which after its purgative operation leaves a certain astringent effect upon the bowels; hence its use in diarrhoea: from two to five grains operates as a tonic, and is very useful in some forms of dyspepsia. A mixture of one part of rhubarb with two of powdered sulphate of potash is an excellent aperient for children. It is occasionally given as a tincture or infusion; but the powder is the best form, cither in a little plain, or peppermint water, or in the form of pill. [s. 1074]