Professor Van Dusen did not speak again. The train pulled into Springfield at nine-twenty. Hatch followed the scientist without a word into a cab.
"Schuyler's candy store," quickly commanded The Thinking Machine. "Hurry."
The cab rushed off through the night. Ten minutes later it stopped before a brilliantly lighted candy store. The Thinking Machine led the way inside and approached the girl behind the chocolate counter.
"Will you please tell me if you remember this man's face?" he asked as he produced Mason's photograph.
"Oh, yes, I remember him," the girl replied. "He's an actor."
"Did he buy a small box of chocolates of you Saturday evening early?" was the next question.
"Yes. I recall it because he seemed to be in a hurry; in fact, I believe he said he was anxious to get to the theater to pack."
"And do you recall that this man ever bought chocolates here?" asked the scientist. He produced another photograph and handed it to the girl. She studied it a moment while Hatch craned his neck, vainly, to see.
"I don't recall that he ever did," the girl answered finally.
The Thinking Machine turned away abruptly and disappeared into a public telephone booth. He remained there for five minutes, then rushed out to the cab again, with Hatch following closely.
"City Hospital!" he commanded.
Again the cab dashed away. Hatch was dumb; there seemed to be nothing to say. The Thinking Machine was plainly pursuing some definite line of inquiry, yet the reporter didn't know what. The case was getting kaleidoscopic. This impression was strengthened when he found himself standing beside The Thinking Machine in City Hospital conversing with the house surgeon, Dr. Carlton.
"Is there a Miss Gertrude Manning here?" was the scientist's first question.
"Yes," replied the surgeon. "She was brought here Saturday night, suffering from--"
"Strychnine poisoning, yes, I know," interrupted the other. "Picked up in the street, probably. I am a physician. If she is well enough I should like to ask her a couple of questions."
Dr. Carlton agreed, and Professor Van Dusen, still followed faithfully by Hatch, was ushered into the ward where Miss Wallack's maid lay, pallid and weak. The Thinking Machine picked up her hand and his slender finger rested for a minute on her pulse. He nodded and seemed satisfied.
"Miss Manning, can you understand me?" he asked.
The girl nodded weakly.
"How many pieces of the candy did you eat?"
"Two," she replied. She stared into the face above her with dull eyes.
"Did Miss Wallack eat any of it up to the time you left the theatre?"
"No."
If the Thinking Machine had been in a hurry previously, he was racing now. Hatch trailed on dutifully behind, down the stairs, and into the cab, whence Professor Van Dusen shouted a word of thanks to Dr. Carlton. This time their destination was the stage door of the theatre from which Miss Wallack had disappeared.
The reporter was muddled. He didn't know anything very clearly except that three pieces of candy were missing from the box. Of these the maid had eaten only two. She had been poisoned. Therefore, it seemed reasonable to suppose that if Miss Wallack had eaten the third piece she also would be poisoned. But poison would not make her invisible. At this point the reporter shook his head hopelessly.
William Meegan, the stage doorkeeper, was easily found.
"Can you inform me, please," began The Thinking Machine, "if Mr. Mason left a box of candy with you last Saturday night for Miss Wallack?"
"Yes," Meegan replied good-naturedly. He was amused at the little man. "Miss Wallack hadn't arrived. Mason brought a box of candy for her nearly every night and usually left it here. I put the one Saturday night on the shelf here."
"Did Mr. Mason come to the theatre before or after the others on Saturday night?"
"Before," replied Meegan. "He was unusually early, I suppose, to pack."
"And the other members of the company coming in stop here, I imagine, to get their mail?" and the scientist squinted up at the mail box above the shelf.
"Sure, always."
The Thinking Machine drew a long breath. Up to this time there had been little perplexed wrinkles in his brow. Now they disappeared.
"Now, please," he went on, "was any package or box of any kind taken from the stage on Saturday night between nine and eleven o'clock?"
"No," said Meegan positively. "Nothing at all until the company's baggage was removed at midnight."
"Miss Wallack had two trunks in her dressing room?"
"Yes. Two whacking big ones too."
"How do you know?"
"Because I helped put 'em in and helped take 'em out," replied Meegan sharply. "What's it to you?"
Suddenly The Thinking Machine turned and ran out to the cab, with Hatch, his shadow, close behind.
"Drive, drive as fast as you know how to the nearest long-distance telephone!" the scientist instructed the cabby. "A woman's life is at stake."
Half an hour later Professor Van Dusen and Hutchinson Hatch were on a train rushing back to Boston. The Thinking Machine had been in the telephone booth for fifteen minutes. When he came out Hatch had asked several questions, to which the scientist vouchsafed no answer. They were perhaps thirty minutes out of Springfield before the scientist showed any disposition to talk. Then he began, without preliminary, much as he was resuming a former conversation.
"Of course if Miss Wallack didn't leave the stage of the theater she was there," he said. "We will admit that she did not become invisible. The problem therefore was to find her on the stage. The fact that no violence was used against her was conclusively proved by half a dozen instances. No one heard her scream; there was no struggle, no trace of blood. Ergo, we assume in the beginning that she must have consented to the first steps which led to her disappearance. Remember her attire was wholly unsuited to the street.
"Now let us shape a hypothesis which will fit all the circumstances. Miss Wallack had a severe headache. Hypnotic influence will cure headaches. Was there a hypnotist to whom Miss Wallack would have submitted herself? Assume there was. Then would that hypnotist take advantage of his control to place her in a cataleptic condition? Assume a motive and he would. Then, how would he dispose of her?
"From this point questions radiate in all directions. We will confine ourselves to the probable, granting for the moment that this hypothesis, the only one which fits all the circumstances, is correct. Obviously, a hypnotist would not have attempted to get her out of the dressing room. What remains? One of the two trunks in her room.
Hatch gasped. "You mean you think it possible that she was hypnotized and placed in that second trunk, the one that was strapped and locked?" he asked.
"It's the only thing that could have happened," said The Thinking Machine emphatically; "therefore that was just what did happen."
"Why, it's horrible!" exclaimed Hatch. "A live woman in a trunk for forty-eight hours? Even if she was alive then, she must be dead now."
The reporter shuddered a little and gazed curiously at the inscrutable face of his companion. He saw no pity, no horror, there; there was merely the reflection of the workings of a brain.
"It does not necessarily follow that she is dead," explained The Thinking Machine. "If she ate that third piece of candy before she was hypnotized she is probably dead. If it was placed in her mouth after she was in a cataleptic condition the chances are that she is not dead. The candy would not melt and her system could not absorb the poison."
"But she would be suffocated-her bones would be broken by the rough handling of the trunk-there are a hundred possibilities," the reporter suggested.