233. Reubarbrum: hot and dry in the second degree; it is the root of a tree that grows in India; there are two sorts of it, barbarum which is called ‘rhu barbarum’, from the country named Barbara, and ponticum, called ‘rhu ponticum’, which is named from the island named Pontus, or perhaps from the pontic taste that it has; it is at its best when it is heavy without holes in it, and, when it is broken, it has foxy red fibres in it, and, when it has been wetted and you put it on your finger nail, the colour of it is deep yellow; it retains its efficacy for merely three years, and it does not have the laxative virtue from that time on; it purges the choleric humour principally, and the melancholic humour secondarily. Take two dragmas of the roots of rhubarb, and as much again of cassia fistula, and put them in the water in which has been boiled melons, citruls and cucumbers, and leave them there for a night, strain them the following morning, give them to drink the following morning, and this will comfort the excessive heat of the liver and spleen, it will help with the fever called hemitritaeus, and it will help with tertian fever, both simple and compound. Item, if powder of rhubarb be given in a spoonful of juice of endive, it will help with jaundice, and it will greatly serve to soothe the appetite when it is weakened by excess of the choleric humour. Its characteristic action is to comfort the brain and the heart, and it soothes the vision and it kills the worms of the intestines.