Twenty lbs. white potato starch, 20 lbs. wheat starch, 20 lbs. Prussian blue, 2 lbs. indigo carmine, and 2 lbs. finely-ground gum-arabic are mixed in a trough, with the gradual addition of sufficient water to form a half-fluid, homogeneous mass, which is then poured out on a board with strips tacked to the edges. It is then allowed to dry in a heated room until it does not run together again when cut. It is next cut, by a suitable cutter, into little cubes, and allowed to dry perfectly. They are finished by being placed in a revolving drum, with a suitable quantity of dry and finely pulverized Paris blue, until they have a handsome appearance. The cost is about 12 cents per pound.