The absolute failure of Eldridge's hypothesis immediately threw public confidence into a profound reaction. Certainty gave place to complete distrust. Rumor gained ground. The exodus increased. Where formerly only those who could do so without great sacrifice or inconvenience had left town, now people were beginning to cut loose at any cost. Men resigned their positions in order to get their families away; others began to arrange their affairs as best they might, as though for a long vacation. As yet panic had not appeared openly in the light of day, but she lurked in the shadows of men's hearts.

The railroads and steamboats were crowded beyond their capacity. Extra trains followed one another as close together as the block signals would allow them to run. Humanity packed the cars. It was like a continual series of football days. In three of them it was estimated that two hundred thousand people had left Manhattan. It would have been physically impossible for the transportation lines to have carried a thousand more. They had reached their capacity; the spigot was wide open.

Percy Darrow showed Jack the head-lines to this effect.

"Cheerful thought," he suggested. "Suppose the whole four million should want to get out at the same time!"

Eldridge had come back to the wireless office thoroughly bewildered. It is a well-known fact that the exact scientist is the hardest man to fool, but the most fooled if fooled at all. Witness the extent to which noted scientists have been taken in by faking spiritualist mediums. So with Eldridge. His hypothesis had been so carefully worked out that the failure of its logic threw his mind into confusion. Until he could discover the weak link in his chain of reasoning, that confusion must continue.

An hour and a half after the bulletin announcing the failure of the search had been posted, Eldridge rushed into the wireless office. The plague of darkness had lifted after fifteen minutes' duration.

"Call Monsieur X," he gasped to the day operator. In fifteen minutes, by rapid substitutions of batteries to weaken or strengthen the sending current, he had redetermined his previous data. Apparently, without the shadow of a doubt, Monsieur X was within the circle.

"He may be at sea," suggested the operator.

But Eldridge shook his head. The circle of the sea had been well patrolled, and for days.

"Begin over again," drawled Darrow. "I told you that you were on the wrong track."

Eldridge glanced at him.

"I can't say that you've done much!" said he tartly.

"No?" queried Darrow, with one of his slow and exasperating smiles. "Perhaps not. But you'd better get to thinking. You won't be able always to take things easy. You may have to hustle before long."

"There has been, I admit," said Eldridge stiffly, repeating in substance the interview he had already given out, "some flaw in our chain of reasoning. This it will be necessary to review with the object of revision. Every physical manifestation must have some physical and definite cause; and this can be found if time enough is bestowed on it. Often the process of elimination is the only method by which the truth can be determined."

Darrow chuckled.

"Look out the process of elimination doesn't overtake you," he remarked.

Eldridge detailed the same reasoning, at greater length, to the men who had employed him. These were very impatient. Business was being not merely ............