"Do get out quick," she cried. "If it does it again while you're half in and half out, you'll be cracked in two as neatly as a walnut."
Gimblet hurried out, clutching the precious box. No sooner was he safely standing on the turf than the door shut again with a violence that gave Pandora the appearance of shaking with convulsions of silent merriment.
"I wasn't sure how it opened," said Lady Ruth, "but I tried all the horns and got it right at last. How lucky I was with you!"
"Yes, indeed," said Gimblet. "I am very thankful you were."
They twisted the horn again, and stood together to watch the recurring phenomenon of the closing door.
"It must be worked by clockwork," the detective said, and taking out his watch he timed the interval that elapsed between the opening and shutting. "It stays open for thirty seconds," he remarked after two or three experiments. "No doubt the mechanism is concealed in the thickness of the stone. At all events it seems to be in good working order."
Squatting on the grass, he opened the tin box, and examined the papers with which it was filled. A glance showed him that they were what he expected, and he replaced the box where he had found it, while Lady Ruth manipulated the horn of the bull.
"I have no right to the papers," he explained to her, as they walked homeward in the gathering dusk. "It would be more satisfactory if a magistrate were present at the official opening of the statue, and I will see what can be done about that to-morrow. In the meantime, and considering that we have been interfering with other people's property, I shall be much obliged if you will keep our discovery secret."
And talking in low, earnest tones, he explained to her more fully all that was likely to be implied by the papers they had unearthed.