“Wait a minute,” went on the farmer, as the two men endeavored to push past him into the house. “Where are you going?”

“To get the patient and take him back to the asylum.”

“Well, I’d wait a bit about that if I were you,” went on Mr. Knowlton grimly. “Now look here,” he went on, producing a shotgun from behind one of the porch pillars. “I’ll give you fellows just one minute to run down the road and make yourselves scarce in any direction you like. Just one minute, and several seconds of that have already passed!” he added significantly, as he raised the gun.

“But I say—look here!” broke out one of the men.

“Half a minute gone!” said the inexorable farmer.

“You don’t understand!” began the other plotter.

“I understand how to use a shotgun!” said Mr. Knowlton. “There’s about fifteen seconds of that minute left and——” He cocked the gun.

But the two men did not stay to argue longer. With black looks and shaking their fists at the imperturbable farmer, they ran out of the gate, and with a grim chuckle Mr. Knowlton returned to Tom to tell what had happened.

“Thank you—a whole lot,” said the young inventor. “They are desperate men. They are going to blow up my factory. I must get back at once and look after my father. He is an old man—he may not take my telephone warning seriously. Nor may Ned. I must go there myself!”

“But you aren’t fit to travel!” expostulated Mrs. Knowlton. “One of the hired men could go.”