2.  Bitter cassava (Janipha Manihot, of Kunth; Jatropha Manihot, of Linnaeus; and Manihot utilissima, Pohl).—­This species has a knotty root, black externally, which is occasionally 30 lbs. in weight.  In the root there is much starchy matter deposited, usually along with a poisonous narcotic substance, which is said to be hydrocyanic acid.  The juice of the plant, when distilled, affords as a first product a liquor which, in the dose of thirty drops, will cause the death of a man in six minutes.  It is doubted whether this acid pre-exists in the plant; some suppose it to be generated after it is grated down into a pulp.  It can be driven off by roasting, and then the starch is used in the form of cassava bread.  It is principally from the starch of the bitter cassava that tapioca is prepared by elutriation and granulating on hot plates.  This serves to agglutinate it into the form of concretions, constituting the tapioca of commerce.  This being starch very nearly pure, is often prescribed by physicians as an aliment of easy digestion.  A tolerably good imitation of it is made by beating, stirring, and drying potato starch in a similar way.

The grated starch of the roots, floated in water, is spontaneously deposited, and when repeatedly washed and dried in the sun, forms cassava flour, called “Moussache” by the French.

The juice of the bitter cassava, mixed with molasses and fermented, has been made into an intoxicating liquor, which is much relished by the negroes and Indians.

The concentrated juice of the bitter cassava, under the name of cassareep, forms the basis of the West India dish, “pepper pot.”  One of its most remarkable properties is its highly antiseptic power, preserving meat that has been boiled in it for a much longer period than can be done by any other culinary process.  Cassareep was originally an Indian preparation.

The manioc or cassava is cultivated in America, on both sides of the equator, to about latitude 30 degrees north and south.  Among the mountains of intertropical America, it reaches to an elevation of 3,200 feet.  It is cultivated also in great abundance on the island of Zanzibar, and among the negro tribes of Eastern Africa to the Monomoesy, inclusive; on the west coast of Africa, in Congo and Guinea.  It appears not to have been introduced into Asia.  The farina of the manioc is almost the only kind of meal used in Brazil, at least in the north, near the equator.  An acre of manioc is said to yield as much nutriment as six acres of wheat.  Meyen states, “It is not possible sufficiently to praise the beautiful manioc plant.”  The Indians find in this a compensation for the rice and other cerealia of the Old World.  It has been carried from Brazil to the Mauritius and Madagascar.

The following quantities of Brazilian arrowroot, or tapioca, were imported in the undermentioned years:—­