739. Rhubarb is a purgative, astringent and stomachic. It is used externally in the form of powder to ulcers, to promote a healthy action. It is given internally in diarrhœa, dyspepsia, and a debilitated state of the bowels. Combined with a mild preparation of calomel, it forms an excellent purgative for children. Dose, of the infusion, from one to two ounces; of the powder, from one scruple to half a drachm as a purgative, and from six to ten grains as a stomachic; of the tincture and compound tincture, from one to four drachms; of te compound pill, from ten to twenty grains.