The Captive River By C.T. Muchemwa It was Siba’s eighteenth birthday, but instead of having a party to celebrate, she was standing by the Zambezi River in a thin, white, cotton slip, shivering despite the hot October sun. It was Commitment Day, the day she would be given to Nyami Nyami, the River God, to be his concubine. Nearby stood four Basilwizi singing a doleful song, their voices shrill in the still, stifling air. The women looked sinister in their long white robes and headscarves.