"Must be a pin hole through the wall up near the ceiling," suggested Kris Kringle.
The silver thread shot across the chamber, ending abruptly on the adobe floor some three feet from the back wall.
"That's the spot!" shouted Mr. Marquand triumphantly.
He threw himself on the floor, and with his knife scratched a cross on the spot where the moonbeam rested. Scarcely had he done so when the delicate shaft of light disappeared as suddenly as it had come.
"It's gone," breathed the boys.
"But it has pointed the way."
"And we have followed the silver trail to its end," added Ned Rector poetically.
"Bring the tools!" cried Mr. Marquand.
While they were doing so, he struck a match and lighted the lantern that they had brought with them from their camp in the foothills. His first care was to bar the door with the heavy wooden timber that he had cut and which he now slipped into its fastenings.
A close examination of the floor revealed no marks save those put there by the treasure-hunter's knife.