Besides these sources of food, the women cultivate a few plantain-trees,[67] a little maize,[68] and the invaluable _yuca_ or manioc, from which they manufacture their two most popular alimentary products, _mazata_ and _fariña_. There are two kinds of _yuca_--the wild-yuca or _yuca brava_[69] and the cultivated variety,[70] both of which are very much used in the whole Amazon Valley. The former contains, however, besides its nutritive elements, a milky sap, which is one of the most virulent vegetable poisons known, its active principle being hydrocyanic acid, but, as the sap is volatile, it is easily removed from the farine by means of pressure and evaporation. In the preparation of the _mazata_, the favourite beverage of these Indians, the _yuca_ is peeled and boiled in but little water in one of their large pots, after which it is smashed to paste by means of a club. This process concluded, the next step is to take out a proper proportion of this mass and mix it with saliva, in the same manner as the Incas do with their scalded maize. The _yuca_ thus prepared is then well mixed with the other, the pot is carefully covered, and the preparation is left to ferment several days, when it is ready for consumption. This _mazata_ does not differ much in taste from the maize-_mazata_ of the Incas. The civilised inhabitants of this region prepare this beverage in a less repugnant and more hygienic way--that is, they add to the paste sugar-cane juice or the juice of a ripe plantain, in place of the saliva. In preparing the _fariña_, the _yuca_ is thrown into a trough filled with water and left there until it is in a state of semi-putrefaction, when it is taken out, peeled, and pulverised. If it is the cultivated variety, it is then dried and put through a roasting process upon hot plates, but if it is the yuca_ brava_, the poisonous sap must first be removed. To do this, the _yuca_, already pulverised, is wrapped up in a good-sized piece of _llanchama_--the tough, inner bark of a tree of the same name--which is then twisted up and tightened with a stick, after the fashion of a tourniquet, until the sap is all pressed out and evaporated. It is then dried and roasted in the same way as the other _yuca_. This _fariña_ can be preserved for a long time if kept dry, and it forms one of the chief articles of food of many of the inhabitants of the Amazon, especially when they are travelling. It is eaten either dry with water or, best of all, with milk and sugar, when it becomes an agreeable, as well as a wholesome, article of food.