"I shouldn't think they would," retorted Oliver. "Why don't you experiment on yourself?"

"I would willingly, but there are two impediments. I cannot at once be operator and subject. Besides, I am too old. My natural force is abated, while you are young, strong, and vigorous. Oh, yes," and he looked gloatingly at our hero, "you will be a capital subject."

"Look here," said Oliver desperately, "I tell you I won't be a subject."

"Then I must proceed without your permission," said the old doctor calmly. "I have already waited too long. I cannot let this opportunity slip."

"If you kill me you will be hanged!" exclaimed Oliver, the perspiration starting from every pore.

"I will submit cheerfully to an ignominiousdeath, if time is only given me to complete and announce my discovery," said the old man composedly.

Evidently he was in earnest. Poor Oliver did not know what to do. He determined, however, to keep the old man in conversation as long as possible, hoping that help might yet arrive, and the struggle—for he meant to fight for his life—be avoided.

"Did you have this in view when you invited me to dine with you?" he asked.

"Surely I did."

"Why did you select me rather than someone else?"