“It doesn’t sound very pleasant,” admitted the boy. “There it comes again!” he cried, as, once more, the mysterious noise filled the black tunnel, which the lanterns of the boys seemed to make only the darker.
Around them, above them, on all sides of the lads circulated that weird sighing, howling, groaning and yelling noise, as though hundreds of imps of blackness were calling to each other in the gloom, laughing in fiendish glee at the plight of the boys.
Ruddy once more howled dismally, ending with such a queer note of protest in his voice that, in spite of his fears, Rick laughed.
“What’s the matter, old fellow?” he asked, as he patted the dog’s head. “Can’t you stand a little groaning?”
“If we only knew what it was,” spoke Chot in rather a chattering voice. “Do you reckon that’s just the wind making echoes in here, Rick?”
“First I thought it was the wind, maybe blowing through holes in the rocks,” said Rick. “I remember reading in the book ‘Tom Brown’s Schooldays’ how there was a ‘blowing stone’ as it was called. A man in an inn blew through a hole in the stone back of the fireplace and the sound came out of a hill half a mile off. I thought maybe it was like that here, but there’s no wind.”
“No,” agreed Chot, “or, anyhow, there isn’t enough wind to make all those howls. It blows a little, but not enough for that.”
The boys, as I have told you, noticed a wind blowing toward them through the tunnel as soon as they opened the closed end by removing the barrier stones. And after entering the black horizontal shaft they had been aware of a constant current of air in their faces, showing that there was an opening at the farther end which they had not yet reached. But, as Chot remarked, there was not enough of the wind, or air current, to account for the noises.
“If the wind made it,” said Chot, “we’d feel a sudden breeze as soon as the sound came.”
“That’s right,” agreed Rick.