The leaves are the only parts used although the active principle, cocaine, is present in small quantities in all parts of the plant. As soon as the shrubs are several years old the leaves are picked, usually several times each year. This work is done principally by women and children who pick the leaves by hand and place them in aprons. They are then spread upon large mats, awnings, or cemented floors, and exposed to the sun for from five or six hours to two or three days. During very warm, bright weather drying may be completed in one day. If the process of drying is slow or if it rains upon the leaves they assume a dark color and are of less value. On the first indications of rain the leaves are placed in sheds specially made for that purpose. Coca leaves have been used for many centuries by the natives of South America who employed them principally as a stimulant, rarely medicinally. The leaves were at one time highly prized. Acosta states that during the reign of the Incas the common people were not permitted to use the leaves without permission from the governor. After the passing of the Incas and after coca was more extensively cultivated all classes chewed the leaves. Children were, however, not allowed to use them. According to Mariani, the young Indian on arriving at the proper age was sent to an old woman whose duty it was to instruct him and to invest him with authority to chew coca leaves. The native carries the leaves in a little pouch (_huallqui_ or _chuspa_) suspended from the belt. This pouch also contains a small bottle-gourd or calabash (_ishcupura_) in which is carried the ash of some plant (species of _Chenopodium_), known as _Llipta_. A few leaves are placed in the mouth and rolled into a ball; a stick moistened with saliva is now dipped into the ash and wiped upon the leaves. The ash is supposed to develop the flavor and to cause a flow of saliva which is either entirely swallowed or partially expectorated. It is said that the use of the leaves enabled the Indians to undergo extreme hardships. A French missionary states that the leaves were absolutely necessary to the slaves employed in the quicksilver mines of Peru. They were also used in dressing wounds, ulcers, and taken internally for the cure of intestinal troubles, jaundice, and various spasmodic troubles. Historians seem to agree that the constant chewing of the leaves by the Indians did not produce any very marked deleterious effects. Mariani, upon the authority of several authors, states that it even seems to be conducive to longevity. The dead of the South American Indians were always supplied with a liberal quantity of coca to enable them to make the long and fatiguing journey to the promised land.