"Certainly."

"Then you had just as much to go on as I did," drawled Darrow, half closing his eyes. The long dark lashes fell across his cheek, investing him in his most harmless and effeminate look.

"I fail to--"

"Yes, you fail, all right," interrupted Darrow. "You had all the strings in your hands, but you were a mile behind me in the solution of this mystery.

I'll tell you why: it was for the same reason that you're going to fail a second time, now that once again I've put all the strings in your hands."

"I must confess I fail to gather your meaning," said Professor Eldridge coldly.

"It was for the same reason that always until his death you were inferior to dear old Doctor Schermerhorn as a scientist. You are an almost perfect thinking machine."

Darrow quite deliberately lighted a cigarette, flipped the match into the grate, and leaned back luxuriously. Professor Eldridge sat bolt upright, waiting. Helen Warford watched them both.

"You have no humanity; you have no imagination," stated Darrow at last.

"You follow the dictates of rigid science, and of logic."

"Most certainly," Eldridge agreed to this, as to a compliment.

"It takes you far," continued Darrow, "but not far enough. You observe only facts; I also observe men. You will follow only where your facts lead; I am willing to take a leap in the dark. I'll have all this matter hunted out while you are proving your first steps."

"That, I understand it, is a challenge?" demanded Eldridge, touched in his pride of the scientific diagnostician.

"That," said Percy Darrow blandly, "is a statement of fact."

"We shall see."

"Sure!" agreed Darrow. "Now, the thing to do is to find Monsieur X. I don't know whether your curiously scutellate mind has arrived at the point where it is willing to admit the existence of Monsieur X or not; but it will. The man who finds Monsieur X wins. Now, you know or can read in the morning paper every fact I have. Go to it!"

Eldridge bowed formally.

"There's one other thing," went on Darrow in a more serious tone of voice.

"You have, of course, considered the logical result of this power carried to its ultimate possibility."

"Certainly," replied Eldridge coldly. "The question is superfluous."

"It is a conclusion which many scientific minds will come to, but which will escape the general public unless the surmise is published. For the present I suggest that we use our influence to keep it out of the prints."

Eldridge reflected. "You are quite right," said he; and rose to go.

After his departure Helen turned on Darrow.

"You were positively insulting!" she cried, "and in my house! How could you?"

"Helen," said Darrow, facing her squarely, "I maintained rigidly all the outer forms of politeness. That is as far as I will go anywhere with that man. My statement to him is quite just; he has no humanity."

"What do you mean? Why are you so bitter?" asked Helen, a little subdued in her anger by the young man's evident earnestness.

"You never knew Doctor Schermerhorn, did you, Helen?" he asked.

"The funny little old German? Indeed, I did! He was a dear!"

"He was one of the greatest scientists living--and he was a dear!

That goes far to explain him--a gentle, wise, child-like, old man--with imagination and a Heaven-seeking soul. He picked me up as a boy, and was a father to me. I was his scientific a.s.sistant until he was killed, murdered by the foulest band of pirates. Life pa.s.ses; and that is long ago."

He fell silent a moment; and the girl looked on this unprecedented betrayal of feeling with eyes at once startled and sympathetic.

"Doctor Schermerhorn," went on Darrow in his usual faintly tired, faintly cynical tone, "worked off and on for five years on a certain purely scientific discovery, the nature of which you would not understand. In conversation he told its essentials to this Eldridge.

Doctor Schermerhorn fell sick of a pa.s.sing illness. When he had recovered, the discovery had been completed and given to the scientific world."

"Oh!" cried Helen. "What a trick!"

"So I think. The discovery was purely theoretic and brought no particular fame or money to Eldridge. It was, as he looked at it, and as the doctor himself looked at it, merely carrying common knowledge to a conclusion.

Perhaps it was; but I never forgave Eldridge for depriving the old man of the little satisfaction of the final proof. It is indicative of the whole man. He lacks humanity, and therefore imagination."

"Still, I wish you wouldn't be quite so bitter when I'm around," pleaded Helen, "though I love your feeling for dear old Doctor Schermerhorn."

"I wish you could arrange to get out of town for a little while," urged Darrow. "Isn't there some one you can visit?"

"Do you mean there is danger?"

"There is the potentiality of danger," Darrow amended. "I am almost confident, if pure reason can be relied on, that when the time comes I can avert the danger."

"Almost--" said Helen.

"I may have missed one of the elements of the case--though I do not think so. I can be practically certain when I telephone a man I know--or see the morning papers."

"Telephone now, then. But why 'when the time comes'? Why not now?"

Darrow arose to go to the telephone. He shook his head.

"Let Eldridge do his best. He has always succeeded--triumphantly. Now he will fail, and he will fail in the most spectacular, the most public way possible."

He lifted his eyes, usually so dreamy, so soft brown. Helen was startled at the lambent flash in their depths. He sauntered from the room. After a moment she heard his voice in conversation with the man he had called.

"Hallowell?" he said, "good luck to find you. Did our friend leave on the _Celtic_? No? Sure he didn't sneak off in disguise? I'll trust you to think of everything. Sure! Meet me at Simmons' wireless in half an hour."

Helen heard the click as he hung up the receiver. A moment later he lounged back into the room.

"All right," he said. "My job's done."

"Done!" echoed Helen in surprise.

"Either I'm right or I'm wrong," said Darrow. "Every element of the game is now certainly before me. If my reasoning is correct I shall receive certain proof of that fact within half an hour. If it is wrong, then I'm away off, and Eldridge's methods will win if any can."

"What is the proof? Aren't you wildly excited? Tell me!" cried Helen.

"The proof is whether or not a certain message has been received over a certain wireless," said Darrow. "I'll know soon enough. But that is not the question; can not you get out of town for a little while?"