Out of the speakers, amazing, booming like the hollow groans that had followed the voices—as they now did!—came the ghostly salutation and warning:
“Hear me! I am the Voice of Doom.”
Again, while they stared at each other with dilated eyes, the needle ran with no pickup. Then, again:
“Hear me! I am the Voice of Doom.”
There rose that whining, shrieking moan of the demented and tortured puppy, lowering in pitch until it became a hoarse and strident howl, slowly falling away in volume but dropping in pitch until it sounded like the moan of wind through stretched silk, ending, as had ended the original, spooky manifestation upstairs, in a grinding, abrupt rumble and silence.
Before the staff got there Roger had developed the sound-films of all the small cameras, but not one had been impressed with picture or audible sound record.
It was uncanny and inexplicable.
The Falcon men and Potts declared solemnly, and with sincerity, that they had seen nothing, had heard nothing.
This supernatural appearance startled even Grover. Though he did not depart from his usual calm or drop his cold poise, he looked more than ever solemn, and even mistrusted human watchers and his electricity-and-water protective device so far as to search the safe.
The jewel, as well as the camphor data and other precious things, to his, and Roger’s, relief, were intact.