Such a thing was alarming enough without any suggestion of the supernatural about it. The force with which the stone struck the ground showed that it had fallen from a considerable height. Jimmy seized Beth by the arm and pulled her to one side of the cave, out of reach of other stones which might come crashing down.
"Oh," gasped Beth, "what is it?"
"Sounds rather like a smuggler's ghost pelting us," said Jimmy. "A damned dangerous thing to do in a place like this without shouting 'Heads' or 'Fore' or any kind of warning."
"Jimmy," said Beth, "I'm terrified."
She was experiencing for the first time in her life a kind of fear which she had often laughed at. It is easy enough to be cheerfully sceptical about ghosts in broad daylight and among familiar things, or to boast of immunity from spookiness when nothing unusual is happening. It is quite another matter when stones take to falling out of a black unknown into a narrow, gloomy place, where every movement and every word make hollow sounds, horribly suggestive of infernal things, when the terrifying crash echoes from rocks on the right, on the left and above, when there is no way of accounting for such happenings. Then cheery scepticism is likely to be chased away by awe. Beth was a prey to the kind of fear in which investigators of the occult find a painful delight, an excruciating ecstasy, which, in apologising to the rest of us, the experimenters call scientific curiosity.
She clung tight to Jimmy's arm with both hands.
For a minute or two they stood waiting and listening. No more stones dropped down the chimney. The noise of tapping and scratching which they had heard ceased. There was complete silence, as dull and heavy as the atmosphere of the cave. It was Jimmy who broke it. He had been puzzled by the noise above him and startled by the falling stone, but he had not felt the fear of the supernatural which had swept over Beth. When he spoke it was in a tone very reassuring to the girl who clung to him.
"Futile sort of old ghost," he said. "I don't call one stone much of a demonstration, do you?"
"But," said Beth, who was recovering her self-possession, "it wasn't really a ghost. I mean to say, it couldn't have been. But what was it? Who dropped the stone?"
"If you ask me, I'm inclined to think——"