“It’s all right, Tom,” the aged inventor made haste to say. “The door and windows of your laboratory were blown out and some of your apparatus damaged by the fire and explosion. But your—the main object is all right,” he finished, and Tom understood.

Before Tom could ask any more questions, Dr. Layton administered a sedative to quiet his patient’s nerves, and, after a few more questions had been answered to the satisfaction of the young inventor, he sank back into a sleep.

Not before, however, he had told his father and the others that he had no idea what had caused the explosion and fire.

“Was it an electrical blast?” Mr. Swift wanted to know. He was aware that often a high tension current may act almost like a blast of dynamite.

“I think not,” Tom had said. “I examined my wires the last thing, after Greenbaum had left the building, and they were all right. The explosion seemed to be coincident with my opening of the door.”

“It were a bomb! Dat’s whut it were—a bomb!” declared Eradicate. “An’ ef I kotches de feller whut done planted it I——”

“That will do now, Rad,” whispered Mrs. Baggert. “Tom must be kept quiet.”

The injured young inventor was now sleeping quietly, and Dr. Layton said he would remain until morning to see how Tom was when he awakened again. Then, the fire being out and no more danger appearing, the house became quiet.

But Mr. Swift had a worried, anxious air. He could not account for that explosion. Some more of Tom’s enemies must be at work, was the conclusion of the aged inventor.

The sun was rising and Tom was just awakening again when the telephone rang. Mrs. Baggert, answering it, brought word that Mary Nestor was on the wire and wanted to know how badly Tom was hurt.