"Not quite," said Foyle quietly. "What's the address of this gambling-joint where you first met him?"

Ike shook his head. "Oh, play the game, guv'nor. You aren't going to have that raided after what I've done for you?"

"We'll see," evaded Foyle. "Where is it?"

Reluctantly, Ike gave the address. Green held out a pen to him and pointed to the bottom of the foolscap.

"Read that through and sign it if it's all right."

The man appended a dashing signature, and with a cheerful "Good night, Mr. Foyle," was ushered by a chief detective-inspector down to the charge-room. Heldon Foyle rested his elbows on the table and remained in deep thought, immobile as a statue. He roused himself with a start as Green returned.

"Both charged," said the other laconically. "The other chap refuses to give any account of himself. Refuses even to give a name. Seems to be a Yankee. I had his finger-prints taken. There was nothing on him to identify him."

"Yankee, eh?" repeated Foyle. "So is Grell. There won't be any one in the finger-print department at this time of night. We'll go along and have a search by ourselves, I think. If we've not got him there, Pinkerton of the U. S. National Detective Agency is staying at the Cecil. We'll get him to have a look over our man and say whether he recognises him."

"Very good, sir. There's one other thing. When I searched this man I found this. I don't know if you can make anything out of it. I can't."

He handed across an envelope already torn open, addressed to "The Advertis.e.m.e.nt Dept., The _Daily Wire_." Within were two plain sheets of notepaper and a postal order. On one was written: "Dear Sir, please insert the enclosed advts. in the personal column of your next issue.--John Jones." On the other were two advertis.e.m.e.nts--

"R.F. You are closely watched. Don't forget 2315. Don't forget 2315. G.

"E. 27.14.5. To-morrow. B."

"Very curious," commented Foyle. "Copy them out carefully and have 'em sent to the paper. They can't do any harm. Now let's get along."

The fog hung heavy over a m.u.f.fled world as they walked down Victoria Street. Green, whose wits were a trifle less supple than those of his chief when imagination was required, put a question. Foyle answered absently. The mysterious advertis.e.m.e.nts were not altogether mysterious to him. He recalled the cipher that had been found at Grave Street, and decided that there was at least room for hope in that direction.

Besides, there was at least one man now in custody who knew something of the mystery, and, even if he kept his lips locked indefinitely, there was a probable chance of a new line of inquiry opening when his ident.i.ty was discovered. And even if finger-prints and Pinkerton failed to resolve that, there was still the resource of the newspapers. With a photograph scattered far and wide, the odds were in favour of some one recognising its subject.

As Foyle switched on the lights in the finger-print department, Green sat down at a table and with the aid of a magnifying-gla.s.s carefully scrutinised the prints which he carried on a sheet of paper. Ranged on one side of the room were high filing cabinets divided into pigeon-holes, numbered from 1 to 1024. In them were contained hundreds of thousands of finger-prints of those known to be criminals. It was for the detectives to find if among them were any identical with those of their prisoner.

The whole science of finger-prints for police purposes resolves itself into the problem of cla.s.sification. It would be an impossible task to compare myriads of records each time. The system employed was absurdly simple to put into execution. In five minutes Green had the finger-prints of the two hands cla.s.sified into "loops" and "whorls" and had made a rough note.

"W.L.W.L.L.

"L.W.W.L.W."

That done, the remainder was purely a question of arithmetic. Each whorl was given an arbitrary number according to its position. A whorl occurring in the first pair counts 16 in the second, the third 4, the fourth 2, and the fifth 1. Thus Green's effort became--

16--4---- 20 --------- = -- --8.4--1 13

The figure one was added to both numerator and denominator, and Green at once went to the fourteenth pigeon-hole, in a row of the filing cabinet numbered 21. There, if anywhere, he would find the record that he sought. For awhile he was busy carefully looking through the collection.

"Here it is," he said at last and read: "Charles J. Condit. American.

No. 9781 Habitual Convicts' Registry."

"Put 'em back," said Foyle. "We'll find his record in the Registry."

The two detectives, uncertain as to where the regular staff kept the files of the number they wanted, were some little time in searching. It was Foyle who at last reached it from a top shelf and ran his eye over it from the photograph pasted in the top left-hand corner to the meagre details given below.

"This is our man right enough," he said. "American finger-prints and photograph supplied by the New York people when he took a trip to this country five years ago. Never convicted here. It says little about him.

We'll have to cable over to learn what they know."

"That gives us a chance for a remand," remarked Green.

"Exactly. And in the meantime he may tell us something. A prisoner gets plenty of time for reflection when he's on remand."

CHAPTER XXVIII

Five minutes after Big Ben had struck ten o'clock Heldon Foyle walked into his office to find Sir Ralph Fairfield striding up and down and glancing impatiently at the clock. He made no direct answer to the detective's salutation, but plunged at once into the object of his visit.

"Have you seen the _Wire_ this morning?" he asked abruptly.

Foyle seated himself at his desk, imperturbable and unmoved.

"No," he answered, "but I know of the advertis.e.m.e.nt that brought you here. As a matter of fact, I sent it to the paper. I should have called on you if you hadn't come. Grell meant it for you, right enough."

The significance of the detective's admission that he knew of the advertis.e.m.e.nt did not immediately strike Fairfield. He unfolded a copy of the _Daily Wire_.

"What do you make of the infernal thing?" he demanded. "It's absolute Greek to me."

With a letter selected from the pile of correspondence on his desk unopened in his hand, Heldon Foyle swung round and faced his questioner.

"It's simply a sighting shot, Sir Ralph," he remarked quietly. "Grell credits you with intelligence enough to remember that number later. Have you any knowledge of ciphers?"

"I have an elementary idea that to unravel them you work from the most frequently recurring letter; E, isn't it?"

"That's right," said Foyle. "But there are other ciphers where that system won't work. Mind you, I don't pose as an expert. If I had a cipher to unravel, I should go to a man who had specialised in them, exactly as I should go to a doctor on a medical question. Still, the advertis.e.m.e.nt to-day isn't a cipher. It means exactly what it says."

"Thank you," said Fairfield drily. "I am now as wise as when I started."

"Sorry," murmured Foyle suavely. "You'll be wiser presently. The thing isn't complete yet. If you'll excuse me a few minutes, I'll just run through my letters, and then, if you don't mind taking a little walk, we'll go and see Lady Eileen Meredith."

Some formal reply rose to Fairfield's lips--he never knew what. The last time he had seen Eileen was fixed in his memory. Then she had practically denounced him as a murderer. Since then she had learnt that every shadow of suspicion had been cleared away from him. How would she receive him if he visited her unexpectedly with Foyle? Why did Foyle wish him to go? Perhaps, after all, there was nothing in it. He told himself fiercely that there was no reason why the meeting should embarra.s.s him. Some day, sooner or later, they would have to meet. Why not now? He was hungry for a sight of her, and yet he was as nervous as a child at the thought of going to her.

The slamming of a drawer and the soft click of a key in the lock told that Foyle had finished. He picked up a copy of the _Daily Wire_ and his hat and gloves.

"Now, Sir Ralph," he said briskly, and together they descended the narrow flight of stone steps which leads to one of Scotland Yard's back doors. The detective was apparently in a talkative mood, and Fairfield got no chance to ask the questions that were filling his mind. Spite of himself he became interested in the flow of anecdotes which came from his companion's lips. There were few corners of the world, civilised or uncivilised, where the superintendent had not been in the course of his career. He had the gift of dramatic and humorous story-telling. He spoke of adventures in Buenos Ayres, in South Africa, Russia, the United States, and a dozen other countries, of knife-thrusts and revolver shots, of sand-bagging and bludgeoning, without any suspicion of vaunting himself. The baronet made some comment.

"No," said Foyle. "Take it all round, a detective's life is more monotonous than exciting. It's taken me thirty years to collect the experiences I'm telling you about. Things always happen unexpectedly.

Some of my narrowest squeaks have taken place in England, in the West End. Why, I was nearly shot in one of the best hotels by an officer sent over from the United States to take charge of a man I had arrested. He was the sheriff of some small town and had a bit of a reputation as a gun-man, and had come over with the district attorney to escort the chap back. They did themselves well while they were here waiting to catch a boat back. One morning I strolled into the hotel, and who should run into me but the attorney with a face the colour of white paper.

"'That you, chief?' he gasps. 'For G.o.d's sake don't go upstairs. ----'s on the landing, blazing drunk and with his gun out. He's a dead shot.'

"Well, I could see that a Wild West sheriff was out of place in a decent hotel, so up I went. He had me covered like a flash, and I yelled out to him not to shoot.

"'h.e.l.lo, chief,' he says. 'That's all right. Come right up. I won't do a thing. Just wait till I've plugged that cur of an attorney and we'll go and have a drink.'