“What is the trouble?” she repeated, anxiously.  “Please tell me.  Is there anything wrong?”

“No—­nothing,” reassured Locke, in spite of his own doubt.  “Everything is all right.”

“I hope so.”  Eva lingered.  “Good night.”

Locke bowed admiringly.  But there was the same restraint in his look that had been shown in the afternoon.

“Good night,” he murmured, slowly.

Eva quite understood, and there was a smile of encouragement on her face as she turned away and flitted down the hall to her room.

Outside, Zita had hurried from the house to the nearest public telephone-booth and was frantically calling Balcom at his apartment.

“Mr. Balcom,” she repeated, breathlessly, as the junior partner answered, “Flint has returned.  I have seen him.”

“The devil!” exclaimed Balcom, angrily, then checked himself before he said any more.  “Keep me informed.”

Abruptly he hung up.

It was scarcely a moment later that Paul Balcom entered the Balcom apartment, admitted by a turbaned black suggestive of the Orient.

Paul was surly and had evidently been drinking, for he shoved the servant roughly out of the way as he strode toward his father.

Apparently outside Paul had overheard and had gathered the drift of what Balcom had been saying.  Or perhaps, from his own sources of information, he already knew.  At any rate, as Balcom turned from the telephone, father and son faced each other angrily.

“Brent’s lying,” exclaimed Paul.  “That marriage to me must take place to-morrow.”

Talking angrily, sometimes in agreement, at others far apart, the two left the room.

Back in the dining-room by this time Brent had rejoined Flint and now watched him eagerly as he took the last wrappings from the package which he had carried so carefully.

As the last wrapping was stripped from it, on the table before them lay a small steel model, perhaps three feet high—­a weird-looking thing in the miniature shape of a man, designed along lines that only a cubist could have conceived—­jointed, mobile, truly a contrivance at which to marvel.

Brent gazed incredulously at the strange thing.  “An automaton!” he exclaimed.

“More than that,” replied Flint, calmly.

Flint unrolled a chart of the human nervous system and spread it out on the table.  Pointing to the brain, he leaned over tensely, and whispered: 

“This model is merely a piece of mechanism.  But the real automaton possesses a human brain which has been transplanted into it and made to guide it.”

For a moment Brent listened incredulously, then sat back in his chair and laughed skeptically.  But even Flint recognized that there was a hollowness in the laughter.

“Do you mean to tell me,” demanded Brent, “that a human brain has been made to control a thing of no use except as a terrible engine of destruction?”