"Gracious me!" gasped the girl.
"What's the matter now?"
"That's the bell to the new vault."
"I don't understand."
"There is an electric button in the vault. When you push it, it unlocks the door and rings this bell. It was put there in case somebody was in the vault in a trance and came to life again."
"What!" ejaculated Sam. "Then that rascal must have pushed the button and opened the door from the inside."
"Yes."
"I'm off. He is not going to escape if I can help it." And so speaking, the youngest Rover dashed off the porch of the cottage and in the direction from whence he had come.
It did not take him long to reach the new vault and a glance through the open doorway showed him that his bird had flown.
"What a dunce I was not to think of that electric button!" he mused. "I knew Mrs. Singleton had stipulated it should be put in. She has a perfect horror of being buried alive."