“And someone is following them,” she discerned. “It looks like Mr. Johnson.”
Professor Bettenridge and his wife now were near the trees. Their voices, though low, carried to those in hiding.
“That stupid lout, Webb!” the professor muttered. “He has ruined everything now by setting off the mine too soon.”
“But how could it have been Webb?” his wife protested. “He was at the farmhouse only five minutes ago. He wouldn’t have had time.”
“Then it was someone else—” Professor Bettenridge paused, and cast a quick alert glance about the lake shore. He noted that the boat was tied, but that the door of the shack was wide open.
“We’ve been exposed!” he muttered. “Our game is up, and we’ve got to get away from here before the authorities arrest us.”
“But what about Johnson?” his wife demanded, glancing over her shoulder at the man who was following them down the hillside path.
“We can do nothing now. He had begun to catch on even before tonight, and this explosion finishes everything. Don’t even stop to pack your clothes. We’ll get our car and clear out.”
“Webb?”
“He’ll have to look out for himself. We’re traveling alone and traveling fast.”