Backwell Street, in the City of London, contains one palatial building which at one time was the headquarters of the South American Stock Exchange, a superior bucket shop which on its failure had claimed its fifty thousand victims. The ornate gold lettering on its great plate-glass window had long since been removed, and the big brass plate which announced to the passerby that here sat the spider weaving his golden web for the multitude of flies, had been replaced by a modest, oxidized scroll bearing the simple legend:

SAUL ARTHUR MANN

What Mr. Mann's business was few people knew. He kept an army of clerks. He had the largest collection of file cabinets possessed by any three business houses in the City, he had an enormous post bag, and both he and his clerks kept regulation business hours. His beginnings, however, were well known.

He had been a stockbroker's clerk, with a passion for collecting clippings mainly dealing with political, geographical, and meteorological conditions obtaining in those areas wherein the great Joint Stock Companies of the earth were engaged in operations. He had gradually built up a service of correspondence all over the world.

The first news of labor trouble on a gold field came to him, and his brokers indicated his view upon the situation in that particular area by "bearing" the stock of the affected company.

If his Liverpool agents suddenly descended upon the Cotton Exchange and began buying May cotton in enormous quantities, the initiated knew that Saul Arthur Mann had been awakened from his slumbers by a telegram describing storm havoc in the cotton belt of the United States of America. When a curious blight fell upon the coffee plantations of Ceylon, a six-hundred-word cablegram describing the habits and characteristics of the minute insect which caused the blight reached Saul Arthur Mann at two o'clock in the afternoon, and by three o'clock the price of coffee had jumped.

When, on another occasion, Senor Almarez, the President of Cacura, had thrown a glass of wine in the face of his brother-in-law, Captain Vassalaro, Saul Arthur Mann had jumped into the market and beaten down all Cacura stocks, which were fairly high as a result of excellent crops and secure government. He "beared" them because he knew that Vassalaro was a dead shot, and that the inevitable duel would deprive Cacura of the best president it had had for twenty years, and that the way would be open for the election of Sebastian Romelez, who had behind him a certain group of German financiers who desired to exploit the country in their own peculiar fashion.

He probably built up a very considerable fortune, and it is certain that he extended the range of his inquiries until the making of money by means of his curious information bureau became only a secondary consideration. He had a marvelous memory, which was supplemented by his system of filing. He would go to work patiently for months, and spend sums of money out of all proportion to the value of the information, to discover, for example, the reason why a district officer in some far-away spot in India had been obliged to return to England before his tour of duty had ended.

His thirst for facts was insatiable; his grasp of the politics of every country in the world, and his extraordinarily accurate information concerning the personality of all those who directed those policies, was the basis upon which he was able to build up theories of amazing accuracy.

A man of simple tastes, who lived in a rambling old house in Streatham, his work, his hobby, and his very life was his bureau. He had assisted the police times without number, and had been so fascinated by the success of this branch of his investigations that he had started a new criminal record, which had been of the greatest help to the police and had piqued Scotland Yard to emulation.

John Minute, descending from his cab at the door, looked up at the imposing facia with a frown. Entering the broad vestibule, he handed his card to the waiting attendant and took a seat in a well-furnished waiting room. Five minutes later he was ushered into the presence of "The Man Who Knew." Mr. Mann, a comical little figure at a very large writing table, jumped up and went halfway across the big room to meet his visitor. He beamed through his big spectacles as he waved John Minute to a deep armchair.

"The chief commissioner sent you, didn't he?" he said, pointing an accusing finger at the visitor. "I know he did, because he called me up this morning and asked me about three people who, I happen to know, have been bothering you. Now what can I do for you, Mr. Minute?"

John Minute stretched his legs and thrust his hands defiantly into his trousers' pockets.

"You can tell me all you know about me," he said.

Saul Arthur Mann trotted back to his big table and seated himself.

"I haven't time to tell you as much," he said breezily, "but I'll give you a few outlines."

He pressed a bell at his desk, opened a big index, and ran his finger down.

"Bring me 8874," he said impressively to the clerk who made his appearance.

To John Minute's surprise, it was not a bulky dossier with which the attendant returned, but a neat little book soberly bound in gray.

"Now," said Mr. Mann, wriggling himself comfortably back in his chair, "I will read a few things to you."

He held up the book.

"There are no names in this book, my friend; not a single, blessed name. Nobody knows who 8874 is except myself."

He patted the big index affectionately.

"The name is there. When I leave this office it will be behind three depths of steel; when I die it will be burned with me."

He opened the little book again and read. He read steadily for a quarter of an hour in a monotonous, singsong voice, and John Minute slowly sat himself erect and listened with tense face and narrow eyelids to the record. He did not interrupt until the other had finished.

"Half of your facts are lies," he said harshly. "Some of them are just common gossip; some are purely imaginary."

Saul Arthur Mann closed the book and shook his head.

"Everything here," he said, touching the book, "is true. It may not be the truth as you want it known, but it is the truth. If I thought there was a single fact in there which was not true my _raison d'etre_ would be lost. That is the truth, the whole truth, and nothing but the truth, Mr. Minute," he went on, and the good-natured little face was pink with annoyance.

"Suppose it were the truth," interrupted John Minute, "what price would you ask for that record and such documents as you say you have to prove its truth?"

The other leaned back in his chair and clasped his hands meditatively.

"How much do you think you are worth, Mr. Minute?"

"You ought to know," said the other with a sneer.

Saul Arthur Mann inclined his head.

"At the present price of securities, I should say about one million two hundred and seventy thousand pounds," he said, and John Minute opened his eyes in astonishment.

"Near enough," he reluctantly admitted.

"Well," the little man continued, "if you multiply that by fifty and you bring all that money into my office and place it on that table in ten-thousand-pound notes, you could not buy that little book or the records which support it."

He jumped up.

"I am afraid I am keeping you, Mr. Minute."

"You are not keeping me," said the other roughly. "Before I go I want to know what use you are going to make of your knowledge."

The little man spread out his hands in deprecation.

"What use? You have seen the use to which I have put it. I have told you what no other living soul will know."

"How do you know I am John Minute?" asked the visitor quickly.

"Some twenty-seven photographs of you are included in the folder which contains your record, Mr. Minute," said the little investigator calmly. "You see, you are quite a prominent personage--one of the two hundred and four really rich men in England. I am not likely to mistake you for anybody else, and, more than this, your history is so interesting a one that naturally I know much more about you than I should if you had lived the dull and placid life of a city merchant."

"Tell me one thing before I go," asked Minute. "Where is the person you refer to as 'X'?"

Saul Arthur Mann smiled and inclined his head never so slightly.

"That is a question which you have no right to ask," he said. "It is information which is available to the police or to any authorized person who wishes to get into touch with 'X.' I might add," he went on, "that there is much more I could tell you, if it were not that it would involve persons with whom you are acquainted."

John Minute left the bureau looking a little older, a little paler than when he had entered. He drove to his club with one thought in his mind, and that thought revolved about the identity and the whereabouts of the person referred to in the little man's record as "X."