TAPIOCA is obtained from the roots of two plants, Ivfanihot aipi, Pohl., the sweet cassava, and M. utilissima, Pohl., the bitter cassava or tapioca plant. From the facility with which the bitter cassava can be rasped into flour, it is culti vated almost to the exclusion of the sweet variety, which contains in its centre a tough fibrous ligneous cord, which is absent in the bitter variety. The latter, however, contains a. highly acrid and poisonous juice, which is got rid of by heat or by fermentation, so that the cassava bread is quite free from it. When the juice .has been carefully expressed, the fecula or flour is washed and dried in the air without heat, and forms the Brazilian arrowroot of commerce ; but when dried on hot plates, it becomes granular and forms tapioc,a. The plant is not dependent on the rain fall for its growth. About 2000 square miles of land in central Travancore are planted with it. The hill-sides are filled with the plant ; and its adaptability to any soil, and its entire independ ence of the seasons and the water supply, induce the a,gricultural population to use it as an article of diet. With planting all the work of the planter ceases, except watching the plantations against robbers and wild beasts. Almost any soil, except
arid sand, is congenial to the manioc plant. The ground is ploughed or dug up after a rain, and at once planted. Heaps of dried vegetation are sometimes burned, and the ashes turned with the soil before planting. The stems of full - grown plants are cut into pieces of about a foot in length, and laid horizontally in little pits dug in rows, each pit or cavity holding two sticks, one crossing the other. They are then covered with piles of dry leaves of trees, and over them small flat mounds of earth are thrown. The plants stand very close to one another, so much so that two plants per square yard is but a low average. They germinate in about a week, and it is essential that there should be one or two good shovrers of rain within a month after planting. An artificial tapioca is made with gum and potato starch. The granules of this are larger, whiter, and more brittle, and more soluble in cold water than genuine tapioca.—Toinlinson; J: P. langlois ; Journ. Agri-Hort. Socy. xii. p. 175.