"No! Again we have the impossibility or seeming impossibility. I examined that library, both before and after the murder. No shot could have been fired from the outside so that a bullet would reach the old man. If that were the case there would have been an opening in the walls or at the windows or the ventilators. Besides, we have the powder burns on the millionaire's head. We are squarely confronted with a paradox. Riddle me that paradox and we will go a long ways toward finding the man who murdered Stockbridge."

Fosd.i.c.k frowned. "I can't see it at all," he confessed. "I still hold to the theory that we should third degree all of the servants. I've got some of them. If they don't squeal, I'll get the others!"

Drew glanced at his watch. "Personally," he said, "I'm of the opinion that you will not get anything out of them. I think it was a mistake to arrest them. It would have been far better to trail the butler and the doorman and see if they connected with anybody."

"I'm doing this!" exclaimed Fosd.i.c.k with asperity. "I've got charge of this case, Drew. I got charge and I don't want any meddling. I've my own methods."

"All right," said the detective. "All right! I want a check-up on the finger prints and then I'll be going. I had to come to you for this.

You have such an interesting collection."

"Here's your answer!" said the commissioner, rising and striding around the desk. "Take this bullet and look it over. Put it in your pocket.

And----"

Drew turned swiftly. The messenger stood in the doorway. He came forward as Fosd.i.c.k nodded. He pa.s.sed over the hastily developed prints which Drew had taken. The commissioner glanced at them, frowned, held them to the light, then said:

"We'll try these on the Man Who Can't Be Beat! He's the best in the world. He'll know in three minutes who made these prints if the fellow is on our records."

The fingerprint expert nodded to Drew as they entered a huge room which was lined with mahogany cabinets in the manner of a filing system in a mail-order house. Fosd.i.c.k pa.s.sed the five photos into this man's hand.

He smiled as the expert adjusted his gla.s.ses, pulled out a pocket magnifying-gla.s.s, and leaned close up to the prints.

"We're infallible!" exclaimed the Commissioner with superiority. "Watch Pope get your man. He'll hound him out in no time. Eh, Pope?"

The expert was not of a sanguine disposition in the minute which ensued as he ran over the prints, studied them, held them to the light then laid them down on a table and shook his head.

"We have no record of this fellow," he said coldly. "It looks like a man's print. Here's the thumb and here is the middle finger of the right hand, I think. Hard to tell, sometimes. I'd say, as a pretty sure thing, that we have no duplicates in our collection. Shall I look?"

"Yes! Look!" said Fosd.i.c.k.

Drew felt that the case was slipping from him as Pope fluttered from cabinet to cabinet, pulled out drawers, replaced them and tried still others.

"No go?" he asked as the expert shot back the last cross-index cabinet and turned with shaking head. "No go? Try again."

"Absolutely no record of the maker of these prints," said Pope, holding out the photos. "He hasn't registered with us yet. Whoever made these prints has never been arrested in the United States for a felony."

"How about a misdemeanor?" asked Drew.

"No! They're all in this cabinet. Even if he was picked up on suspicion or for auto speeding or beating his wife,--if he has one,--he would be here. I'm sorry, inspector."

Drew pulled down the lapels of his black coat and turned toward Fosd.i.c.k.

"Have you got a print of Finklestein?" he asked. "You remember the fellow who was arrested in the Morphy case. He was afterwards released for lack of evidence or else he claimed exemption. I've forgotten how he got off. He's supposed to be in Florida or somewhere in the South. I had a man out to Morristown who reports along those lines. I wish you'd compare these prints with Finklestein's."

"Go ahead," said the commissioner. "Go as far as you like. I don't think that there is anything in these prints. You got the wrong ones--that's all."

"What's Finkle--Finklestein's initials?" asked the expert.

"J. B.," said Drew quickly. "Julius B.!"

A quick search through an alphabet-index, a consultation of two drawers, out of which the expert pulled some tiny squares of cardboard, and then a slow shaking of his head, brought Drew back to where he had started from before taking the prints in the booth.

"No record could be more different," Pope said. "Finklestein has a big hand and very broad fingers. The fellow who made these prints has a little hand with thin fingers. The whorls and loops are entirely dissimilar. He comes under cla.s.sification 2-4-X. Finklestein is in cabinet 2-9-0. They couldn't be further away."

Drew started out through the doorway with Fosd.i.c.k following him. They stood on the landing leading to the downstairs steps, where the detective was about to leave the commissioner with a curt good-by. His hand was out when he drew it back, dropped it to his side and wheeled with sudden intuition.

"Good Lord!" he exclaimed. "Are you and I detectives or children? Come back to the fingerprint room. Hurry now. I want to see Pope. I forgot something!"

The expert rose as they entered. "Well?" he asked with arching brows and a slight frown on his face. "Well, what is it?"

Drew pointed a finger as steady as a rifle. He bared his eyes into Pope's own. "Were you up to Stockbridge's house?" he asked swiftly.

"Yes! Why?"

"Did you take prints and photos of everything in the library? I understand that this was done after I turned the case over to Commissioner Fosd.i.c.k."

"It was done!" rasped Fosd.i.c.k. "Of course it was done. It's always done when a case looks like a homicide!"

"This case looked worse than that!" said Drew. "It was slaughter!"

The commissioner turned to the fingerprint man. "Where are the prints and photos you took up at the house?" he asked.

"Still in the developing room."

"Do you think they are developed?"

"I'll soon know, sir," he answered, pressing a b.u.t.ton.

The messenger entered who had attended to Drew's prints which the detective took in the telephone-booth.

"Get down to the developing room," ordered Pope. "Get me all the prints and positives of Exhibit 12 of the Stockbridge case. Bring what is already developed. Tell them to rush the others."

The three men waited in silence for the return of the messenger. Drew paced the floor thoughtfully. He clasped and unclasped his hands behind his back. He had almost slipped in an important matter. It was a chance he was taking, but a vital one in the case. The fingerprints taken by the expert in the library might and might not jibe with those taken in the slot-booth. If they were the same, or any one was the same, the case would offer a new line for investigation.

A sliding footstep at the door announced the messenger. He held a sheath of curling papers in his hand. Pope reached and s.n.a.t.c.hed the photos. He ran over them with widening eyes. He sorted them into two piles upon the table.

"Five prints!" he announced, glancing at Drew with a sly smile. "Five of these prints are the same as your set. In other words, the man who made the impressions in the telephone-booth was also in the library at or about the time of the murder!"

"Impossible!" snorted Fosd.i.c.k.

"Ah!" said Drew. "Photos don't lie. Now we're getting there! That's the first light I've seen in some time. It clears the case of the supernatural. It puts it where it belongs--in the material world of flesh and blood and hate and revenge."

"It does that!" corroborated the expert, siding with Drew. "Now," he added good-naturedly, "I'll help out some more. I've got a book of notations made in the library. I spent two hours there this morning. I flashed every print I could see. There's some of the butler on the bottle and the tray. There's a number on the polished table. There are at least six on the door k.n.o.b, to say nothing of the smashed panel. I suppose yours is among them, inspector?"

Drew held out his right hand. "Look and see," he suggested with a short laugh. "I've never been printed in my life."

"That won't be necessary. These three prints which correspond with the ones you took in the booth, settle the matter. There's no record of this fellow in our cabinet. But--he was in that library!"

"Where did he leave his prints?" asked Drew.

Pope consulted a page of his note book. He thumbed over another page, thrust his finger between the sheet and turned to the photos. "What's the number on the back of that one?" he asked, nodding toward the topmost photograph.