A voice had begun to sing. It was very far away and Digory found it hard to decide from what direction it was coming. Sometimes it seemed to come from all directions at once. Sometimes he almost thought it was coming out of the earth beneath them. Its lower notes were deep enough to be the voice of the earth herself. There were no words. It was hardly a tune. But it was beyond comparison, the most beautiful sound he had ever heard.

The magician's nephew (ed. 1988) - ISBN: 9780590406000