But a son of the chief's, a man of about thirty, had lately set up as a rival in supernatural powers.

This irritated Indaba-zimbi beyond measure, and a quarrel ensued between the two witch-doctors that resulted in a challenge to trial by lightning being given and accepted.

These were the conditions.

The rivals must await the coming of a serious thunderstorm, no ordinary tempest would serve their turn.

Then, carrying assegais in their hands, they must take their stand within fifty paces of each other upon a certain patch of ground where the big thunderbolts were observed to strike continually, and by the exercise of their occult powers and invocations to the lightning, must strive to avert death from themselves and bring it on their rival.