Louder and louder it rose, and then gradually died away.

The soldiers stood as if paralysed.

Even the high official--who had been obliged to leave his horse, and make his way across the fallen blocks on foot--stepped back a pace, with an expression of awe.

He soon recovered himself, and shouted angrily to the men to go on.

But again the dirge-like noise rose, louder and louder.