an acid extracted from amber by sublimation in a gentle heat, and rises in a concrete form into the neck of the subliming vessel. The operation must not be pushed too far, or by too strong a fire, otherwise the oil of the amber rises along with the acid. The salt is dried upon blotting paper, and purified by repeated solution and crystallization.

The acid is soluble in 24 times its weight of cold water, and in a much smaller quantity of hot water. It possesses the qualities of an acid in a very small degree, and only affects the blue vegetable colours very lightly. The affinities of this acid with the fusible bases were determined by Mr de Morveau, who is the first chemist that has endeavoured to ascertain them.