It was on the third day following that Mrs. Roswell hurriedly summoned The Thinking Machine to her home. When he arrived she was deeply agitated.
"Another of the small stones has been stolen from the tiara," she told him hurriedly. "The circumstances were identical with those of the first theft, even to the screaming of the cockatoo. I watched as you suggested, have been watching each night but last night was so weary that I fell asleep. The cockatoo awoke me. Why would Jeanette--"
"Let me see the apartments," suggested the scientist. Thus he was ushered into the room which was the centre of the mystery. Again he examined the tiara, then studied the door of the vault. Afterwards he casually picked up and verified the record of the combination, locked and unlocked the vault twice after which he examined the fastenings of the door and the windows. This done he went over and peered inquisitively at the cockatoo on its perch.
The bird was a giant of its species, pure white, with a yellow crest which drooped in exaggerated melancholy. The cockatoo resented the impertinence and had not The Thinking Machine moved quickly would have torn off his spectacles.
A door from another room opened and a girl-Jeanette-entered. She was tall, slender and exquisitely proportioned with a great cloud of ruddy gold hair. Her face was white with the dead white of illness and infinite weariness was in her eyes. She was startled at sight of a stranger.
"I beg your pardon," she said. "I didn't know--" and started to retire.
Professor Van Dusen acknowledged an introduction to her by a glance and a nod then turned quickly and looked at the cockatoo which was quarrelling volubly with crest upraised. Mrs. Roswell's attention, too, was attracted by the angry attitude of her pet. She grasped the scientist's arm quickly.
"The bird!" she exclaimed.
"Jeanette, Jeanette, Jeanette," screamed the cockatoo, shrilly.
Jeanette dropped wearily into a chair, heeding neither the tense attitude of her step-mother nor the quarrellings of the cockatoo.
"You don't sleep well, Miss Roswell?" asked The Thinking Machine.
"Oh, yes," the girl replied. "I seem to sleep enough, but I am always very tired. And I dream constantly, nearly always my dreams are of the cockatoo. I imagine he calls my name."
Mrs. Roswell looked quickly at Professor Van Dusen. He crossed to the girl and examined her pulse.
"Do you read much?" he asked. "Did you ever read this?" and he held up the copy of "Les Miserables."
"I don't read French well enough," she replied. "I have read it in English."
The conversation was desultory for a time and finally The Thinking Machine arose. In the drawing room down stairs he gave Mrs. Roswell some instructions which amazed her exceedingly, and went his way.
Jeanette retired about eleven o'clock that night and in an hour was sleeping soundly. But Mrs. Roswell was up when the clock struck one. She had previously bolted the doors of the two rooms and fastened the windows. Now she arose from her seat, picked up a small jar from her table, and crept cautiously, even stealthily to the bed whereon Jeanette lay, pale almost as the sheets. The girl's hands were outstretched in an attitude of utter exhaustion. Mrs. Roswell bent low over them a moment, then stole back to her own room. Half an hour later she was asleep.
Early next morning Mrs. Roswell 'phoned to The Thinking Machine, and they talked for fifteen minutes. She was apparently explaining something and the scientist gave crisp, monosyllabic answers. When the wire was disconnected he called up two other persons on the 'phone. One of them was Dr. Henderson, noted alienist; the other was Dr. Forrester, a nerve specialist of international repute. To both he said:
"I want to show you the most extraordinary thing you have ever seen."
The dim light of the night lamp cast strange, unexpected shadows, half revealing yet half hiding, the various objects in Mrs. Roswell's room. The bed made a great white splotch in the shadows, and the only other conspicuous point was the bright silver dial of the jewel vault. From the utter darkness of Jeanette Roswell's room came the steady, regular breathing of a person asleep; the cockatoo was gone from his perch. Outside was the faint night-throb of a city at rest. In the distance a clock boomed four times.
Finally the stillness was broken by a faint creaking, the tread of a light foot and Jeanette, robed mystically in white, appeared in the door of her room. Her eyes were wide open, staring, her face was chalk-like, her hair tumbled in confusion about her head and here and there was flecked with the glint of the night-light.
The girl paused and from somewhere in the shadow came a quick gasp, instantly stifled. Then, unhearing, she moved slowly but without hesitation across the room to a table whereon lay several books. She stooped over this and when she straightened up again she held "Les Miserables" in her hand. Several times the leaves fluttered through her fingers, and thrice she held the book close to her eyes in the uncertain light, then nodded as if satisfied and carefully replaced it as she had found it.
From the table she went straight toward the silver dial which gleamed a reflection of light. As she went another figure detached itself noiselessly from the shadows and crept toward her from behind. As the girl leaned forward to place her hand on the dial a steady ray of light from an electric bell struck her full in the face. She did not flinch nor by the slightest sign show that she was aware of it. From her face the light travelled to each of her hands in turn.
The dial whirled in her fingers several times and then stopped with a click, the bolt snapped and the vault door opened. Conspicuously in front lay the tiara glittering mockingly. Again from the shadows there came a quick gasp as the girl lifted the regal toy and tumbled it on the floor. Again the gasp was stifled.
With quick moving, nervous hands she dragged the jewels out permitting them to fall. She seemed to be seeking something else, seeking vainly, apparently, for after awhile she rose with a sigh, staring into the vault hopelessly. She stood thus for a dozen heart beats, then the low, guarded voice of the second figure was heard-low yet singularly clear of enunciation.
"What is it you seek?"
"The letters," she replied dreamily yet distinctly. There was a pause and she turned suddenly as if to re-enter her room. As she did so the light again flashed in her glassy eyes, and the second figure laid a detaining hand on her arm. She started a little, staggered, her eyes closed suddenly to open again in abject terror as she stared into the face before her. She screamed wildly, piercingly, gazed a moment then sank down fainting.
"Dr. Forrester, she needs you now."
It was the calm, unexcited, impersonal voice of The Thinking Machine. He touched a button in the wall and the room was flooded with light. Drs. Forrester and Henderson, suddenly revealed with Mr. and Mrs. Roswell and Arthur Grantham, came forward and lifted the senseless body. Grantham, too, rushed to her with pained, horror-stricken face. Mrs. Roswell dropped limply into a chair; her husband stood beside her helplessly stroking her hair.
"It's all right," said The Thinking Machine. "It's only shock."
Grantham turned on him savagely, impetuously and danger lay in the boyish eyes.
"It's a lie!" he said fiercely. "She didn't steal those diamonds."
"How do you know?" asked The Thinking Machine coldly.
"Because-because I took them myself," the young man blurted. "If I had known there was to be any such trick as this I should never have consented to it."
His mother stared up at him in open eyed wonder.
"How did you remove the jewels from the setting?" asked The Thinking Machine, still quietly.
"I-I did it with my fingers."
"Take out one of these for me," and The Thinking Machine offered him the tiara.
Grantham snatched it from his hand and tugged at it frantically while the others stared, but each jewel remained in its setting. Finally he sank down on the bed beside the still figure of the girl he loved. His face was crimson.
"Your intentions are good, but you're a fool," commented The Thinking Machine tartly. "I know you did not take the jewels-you have proven it yourself-and I may add that Miss Roswell did not take them."
The stupefied look on Grantham's face was reflected in those of his mother and step-father. Drs. Forrester and Henderson were busy with the girl heedless of the others.
"Then where are the jewels?" Mrs. Roswell demanded.
The Thinking Machine turned and squinted at her with a slight suggestion of irritable reproach in his manner.
"Safe and easily found," he replied impatiently. He lifted the unconscious girl's hand and allowed his fingers to rest on her pulse for a moment, then turned to the medical men. "Would you have believed that somnambulistic sub-consciousness would have taken just this form?" he asked curtly.
"Not unless I had seen it," replied Dr. Henderson, frankly.
"It's a remarkable mental condition-remarkable," commented Dr. Forrester.
It was a weirdly simple recital of the facts as he had found them that The Thinking Machine told downstairs in the drawing room an hour later. Dawn was breaking over the city, and the faces of those who had waited and watched for just what had happened showed weariness. Yet they listened, listened with all their faculties as the eminent scientist talked. Young Grantham sat white faced and nervous; Jeanette was sleeping quietly upstairs with her maid on watch.
"The problem in itself was not a difficult one," The Thinking Machine began as he lounged in a big chair with eyes upturned. "The unusual, not to say strange features, which seemed to make it more difficult served to simplify it as a matter of fact. When I had all the facts I had the solution in the main. It was adding a fact to a fact to get a result as one might add two and two to get four.
"In the first place burglars were instantly removed as a possibility. They would have taken everything, not one small stone. Then what? Mr. Grantham here? His mother assured me that he was quiet and studious of habit, and had an allowance of ten thousand a year. There was no need for him to steal. Then remember always that he no more than anyone else could have entered the rooms. The barred doors excluded the servants too.
"Then we had only you, Mrs. Roswell, and your step-daughter. There would have been no motive for you to remove the jewel unless your object was to throw suspicion on the girl. I didn't believe you capable of this. So there was left somnambulism or a wilful act of your step-daughter's. There was no motive for the last-your daughter has ten thousand a year. Then sleep-walking alone remained. Sleep-walking it was. I am speaking now of the opening of the vault."
Grantham leaned forward in his chair gripping its arms fiercely. The mother saw, and one of her white hands was laid gently on his. He glanced at her impatiently then turned to The Thinking Machine. Mr. Roswell, the alienist, and the specialist, followed the cold clear logic as if fascinated.