JELLY, a form of food, or medicine, prepared from the juices of ripe fruits, boiled to a proper consistence with sugar; or the strong decoctions of the horns, bones, or extremities of animals, boiled to such a height as to be stiff and firm when cold, without the addition of any sugar.—The jellies of fruits are cooling, saponaceous, and acescent, and therefore are good as medicines in all disorders of the primæ vixæ, arising from alkaliescent juices, especially when not given alone, but diluted with water. On the contrary, the jellies made from animal substances are all alkaliescent, and are therefore good in all cases in which an acidity of the humours prevails: the alkaliescent quality of these is, however, in a great measure taken off, by adding lemon juice and sugar to them. There were formerly a sort of jellies much in use, called compound jellies; these had the restorative medicinal drugs added to them, but they are now scarce ever heard of.