“Oh,” Zizi’s eyes lighted up; “of course I did! Those damp, mossy stones. And, then, oh, Wise one, just how did the same stain get on Martha’s hand?”
“That, Zizi,” Wise spoke almost solemnly, “is part of the solution of the whole great mystery.”
CHAPTER XVIII
The Trap
In a small but powerful motor boat Wise went on his voyage of exploration. The man who managed the craft was a stolid, silent person who obeyed Wise’s orders without comment.
But when the detective directed that he go round the base of the headland, and skirt close to the rocks he grumbled at the danger.
“Be careful of the danger,” Wise said, “steer clear of hidden reefs, but go close to the overhanging cliff, there where I’m pointing.”
Skirting the cliff, at last Wise discovered what he was looking for, a small cave, worn in the rock by the sea. The floor of this cave rose sharply and it was with difficulty that Wise managed to scramble from the boat to a secure footing on the slippery wet rocks.
“Look out there,” said the imperturbable boatman, “you’ll get caught in there when the tide comes up. I never noticed that hole in the wall before, it must be out o’ sight ’ceptin’ at low tide.”
“Stay where you are and wait for me,” Wise directed, “if I’m not out here again in half an hour, go on home. But I’ll probably be back in less than that.”
“You will, if you’re back at all! The tide will turn in fifteen minutes and in half an hour it’ll be all you can do to get out!”