"Peter Brent's daughter!" he exclaimed. "No, not his daughter--the daughter of Doctor Q."

"Impossible!" recoiled Zita, astounded at the assertion.

"True, Zita," he asserted, "absolutely true. Here, look at this paper."

With hands that trembled, Zita took the paper and read an amazing table.

Unless the paper lied, she was indeed the daughter of Doctor Q.

There was only one thing to do and that was to confront Doctor Q at once and force him to a full explanation.

In order not to antagonize Paul, Zita was now particularly nice to him.

Her object was to get him to consent to her escape, so that she could inform Locke and Eva of her discovery and all three confront Doctor Q and wrest from him the story.

At first Paul would not let her go unless she consented to marry him, but Zita played him skilfully, so that finally he unlocked the door.

Then Zita flew down the stairs and to a telephone around the corner, where she called up Locke, to whom she told as much as she dared over the wire.

Locke told her that he and Eva would meet her within an hour in the lobby of one of the city's largest hotels, and Zita hastened there, where she waited impatiently until they arrived.

Doctor Q admitted them immediately, and they noticed with astonishment the wonderful change for the better that had taken place in the man. For with the restoration of his mind all the evil lines of his face had been obliterated, as it were, and in the place of the doddering half-imbecile they found a genial, kindly, and distinguished gentleman who, with the utmost hospitality, brought chairs and begged them to be seated.

Zita, in her anxiety to know the truth, could hardly contain her impatience. Tossed from pillar to post, dominated once by the strong, evil mind of Balcom, Zita had run the gamut of human emotions before she had barely passed her girlhood.

Seeing her agitation, Locke undertook to interrogate the doctor.

"Doctor Q," he began, "I believe you know the perpetrator of the crimes to which we have all been subjected, and we have come to you in all friendliness to ask you to clear this mystery up for us. Balcom is dead," added Locke, pointedly.

"Yes, I know that," interrupted Doctor Q.

"You know?" all asked. "How do you know?"

The doctor told of having seen Balcom's body. But at first he could not explain why he was in the spot at the time.

Then Locke went on to tell him of the document that Paul had shown to Zita.

Doctor Q sank heavily into a chair.

"That document that Paul Balcom showed Zita," he exclaimed, after a moment, "told the truth."

All were startled. Zita would have risen with a cry had not Locke gently touched her arm.

"Tell us the story," demanded Locke of Q.

For some moments Doctor Q seemed to be collecting his scattered thoughts, as though still a haze hung over his mind. Then he began to speak, becoming more certain of his strange story.

"It was many years ago," he began, as all drew closer about him, listening breathlessly to his narrative, "and all these years I have been quite mad. The man now lying dead, Balcom, was the cause of all these years of misery."

The old man passed his hand over his head as though to wipe away a recollection of hate and fear, then resumed:

"I was an inventor in those days, and very successful. I had built up a great fortune, had built a great house, and in that house I had a beautiful wife and two of the loveliest children, a boy and a girl, that ever man had."

He paused again, then went on:

"One day, a man entered my life and proposed to put my inventions on the market very advantageously. He was suave, polished, and apparently a gentleman. At any rate, I trusted him. You all knew him. It was Herbert Balcom.

"At the time I did not know that in order to give my inventions a clear field the inventions of hundreds of poor inventors were to be suppressed. I know now, Miss Brent, that your own father was led along in the scheme, even as I was. Balcom possessed the master mind and we were all as children in his hands."

Doctor Q stopped a moment. It was evident that he was speaking with restraint when it came to Peter Brent, perhaps glossing over what the man had done. Though he did not say so, the mere fact that at last Brent had seen the light and had planned a wholesale restitution weighed supremely in Doctor Q's mind.

"One day," he resumed, "Balcom came to me in what I know now was merely feigned excitement and fear. 'They're after us!' he cried. 'Brent and I have done our best--but the government is after you, and we can't protect you any longer.'

"Then for the first time Balcom told me of the real purposes of the company, told me that he had been drawn into it by Brent. It was all a tissue of lies--lies that drove me from my home and country. I hated your father with an undying hate, Miss Brent.

"Well, to make the sad story short, I took my wife and children and sailed secretly for the farthermost parts of the world. Off the coast of Madagascar, in the Straits, a typhoon came up. The vessel was driven on the rocks and wrecked. I was cast ashore, and I vaguely remember how, for days and weeks, I patrolled that beach, subsisting on shell-fish, imploring God, day and night, to restore my wife and children to me.

Then my mind gave way.

"The natives took me in, thinking me a god. They took me many miles inland. Savages, the world over, are superstitious about the demented, and so they treated me kindly. They installed me in a thatched hut of my own and made me a leader.

"How many months, years, I stayed with them I do not know. But, true to my mechanical instinct, I rigged up a forge and improved many of the crude instruments of the natives, principally those of agriculture.

"But transcending every other feeling, I hated Brent. In my madness, I conceived the idea that I would construct an iron giant that, upon its completion, if I could only procure the brain of a man who had died of a lightning stroke or other electric agency, I could, by installing this brain in the brain cavity of the giant, give it volition, make it a superman without feeling or conscience. It was a mad idea--but I was mad.

"At about this time Balcom came to Madagascar. He found me and, knowing my intense hatred of Peter Brent, he cruelly added fuel to the fire.

Already he must have known that Brent was coming to his senses and planning his great restitution to genius.

"He promised me that if I would come to New York with him he would secure an electrocuted brain so that I could perfect my steel automaton and obtain my revenge. I was easily persuaded and I sailed with Balcom, bringing the iron monster with me."

A strange light gleamed in the old man's eyes as he spoke, not the light of madness, but of kindliness now.

"Children," he said, at length, "I have, during these lucid moments, watched you all closely. Call it instinct if you will, but you, Zita, and you, Quentin, seem to be particularly dear to me now. To-day, returning from the scene of the explosion, with every faculty not only clear, but rather sharpened by long disuse, I pieced the years, the months, even the days together. I searched in an old trunk and I found--this."

It was a list of those rescued from the steamer _Magnifique_, and with amazement they read the names among the passengers:

QUENTIN LOCKE ZITA LOCKE

There was a short note at the bottom of the list, to the effect that no trace of either the father or the mother of the two children had been found.

Paper after paper which Doctor Q had found, where they had been preserved by Balcom, proved the identification and the story.

Locke's head was in a whirl at the sudden change in relationships, but not more so than Zita's. Finally Zita could stand the strain no longer.

What had been a hopeless love was now explained.

"My--my brother!" she sobbed, as she buried her head on Quentin's shoulder.

Both turned to Doctor Q--Doctor Q no longer, but really Quentin Locke, senior, whence had come the "Q."

His eyes filled with tears and his voice choked.