I remember a similar kind of "ear" in a natural cave in Matabeleland.
It was here that one of the native sorcerers used to hide himself, and
when he whispered through a crack in the rocks it could be heard all
over the cave.
The people believed that it was the voice of a god speaking to them,
so they used to come and pray to him for advice, and the old villain
told them that they must rise up and murder all the white people, and
their chief, Lobengula, who had long been dead, would come to life and
lead them against their enemies once more.
He had nearly persuaded them to come out on the war-path, when
Burnham, the American scout, made his way into the secret part of the
cave and shot the supposed god while he was preaching murder.
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