A 1951 recording of the Shona song Dendera jikwa by Zimbabwean blind musician Raimon Jaket inspried this piece. Jaket played a chizambi friction bow, and effected a beautiful contrast between the high ethereal sounds made by bowing the bow-stick, and the low mysterious notes that he produced by drawing his breath in past the palm leaf bow-string.
In Shona traditional religion, shavi is the spirit of a person who died far away from home, too distant for rituals to be held to bring that spirit back again. So, the spirit can find a host anywhere to possess. The song Dendera jikwe is about a hornbill shavi spirit, and Raimon Jaket imitates that bird very well on his friction bow. But my version is not very bird-like, and so I think of it as an imitation of any shavi spirit.