In A Spirit Walker's Guide to Shamanic Tools, How to Make and Use Drums, Masks Rattles and other Sacred Implements, Evelyn C. Rysdyk, the author, describes some very special instruments that have purposes that transcend simple music. The huaco silbador, or whistling vessel, is a shamanic instrument that dates back to Pre-Colombian times. In the curanderisimo tradition of the Peruvian North coast, whistling vessels or huaco silbadors are used by the curanderas to call in the spirits for protection and/or healing. The curanderas and curanderos of this tradition are shamanic healers who usually construct an elaborate altar, called a mesa, for their healing ceremonies. These mesas have dozens of power objects placed on them to assist the healer in her or his work & a huaco silbador is often present. Depending upon their shape or dedicated purpose, these vessels may be used to summon different spirit helpers and also to provide a home for the spirit in this realm. For instance, an animal shaped vessel may contain the spirit of the animal, to summon the animal spirit to assist the curandera, or be dedicated for a different purpose which as clearing the space in which the healing is to occur. As with other shamanic objects, it is the enlivening process carried out by the shaman that gives the vessels power.