Reubarbarum quidem ut quidam dicunt est radix cuiusdam arboris: i.e. rhubarb according to some is the root of a tree. It is found resembling a lump. Note particularly that there is a rhubarb called barbarum which is found in barbarian countries such as India and the countries east of the ocean, and another rhubarb called ponticum because it is found on an island called Pontos, or because of its pontic10 taste. And there is another yellow species of it which is mixed with some black and which has firmness, ponticity11, bitterness and piquancy. Nature: they all have the same nature and they are hot and dry in the second degree. They purge choler from the stomach and from the liver and are for that reason suitable in diseases of the stomach and of the liver an example of which is fever. Dosage: it suffices as maximum dose of it by itself or in a syrup up to one half ounce; and as minimum dose of it up to two drams.