Two men singing each in one tube of bamboo, which act as voice-alterers. The mai spirits are represented by men in masks who hide the bamboo tubes under their costumes. Always paired, the young initiated men wore such masks during a ceremony, which had practicaîly disappeared by the 19605. The text mentions the Sepik River and the floating logs that come down it, as well as men with scarifications. » Hugo Zemp, cf. p.48 of booklet