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PART II.

Materia Medica ---- BJtei radix.

473

10; the tincture is deeper coloured, and when evaporated onwater affords the same results as the former kind, except thatthe compound of tannin and extractive is more soluble.

The infusion of Chinese rhubarb is more copiously precipi-tated by solution of isinglass than that of the Russian. Infu-sion of yellow cinchona bark throws down a copious greenishprecipitate from infusion of Russian rhubarb, and a lesscopious, but more dense bright yellow precipitate from that ofChinese rhubarb.

The following Tables show the effects of re-agents on theaqueous infusions of the two varieties of rhubarb.

1