His hand was a strange one for a janitor. It was long and supple, and moved with the smoothness of a musician's hand.

Fritz laid the sheet of paper aside. He drew forth a rag and carefully polished the surface of the desk. He put the paper on the desk and finished his mopping.

Then he returned to the paper and carefully rolled it into a tube which he inserted beneath his overalls. He left the room, walked along the corridor to a locker, removed his overalls and put them away. He stowed the mop and bucket in a corner.

He walked with c.u.mbersome step along the corridor until he reached the outside door and stepped out.A policeman was standing there.

"Good night, Fritz," he called.

"Yah," was the grunted reply.

Fritz shambled around a corner and entered the silence of a narrow alley. Then his form merged with the blackness. Fritz, the janitor, literally had vanished.

A coupe stood a short distance down the alley. Its door seemed to open of its own accord. There was an almost inaudible sound of some garment being swished along the upholstery of the car.

A few moments later, the coupe pulled away. It rolled by police headquarters, then went rapidly uptown, and stopped in another obscure parking place. Here, again, the door seemed to open automatically. Not even the closest observer could have seen a black-clad figure emerging from the interior of the car.

Ten minutes later, a light clicked in a small room. A green-shaded lamp cast a luminous circle upon the surface of a table.

Two hands appeared in the lighted spot. They were those same long-fingered hands that had wiped the desk in police headquarters. The only difference lay in the left hand. Upon it glowed a mysterious gem, a fire opal that shone with the peculiar dim spark of a dying ember.

The hands of The Shadow were at work!

Those hands were both nimble and active. They constantly disappeared and reappeared, each time with a definite purpose.

They brought into view that same rolled sheet of thin paper that Fritz the janitor had pressed upon his desk in police headquarters. The hands spread out the paper.

One fingernail scratched the corner of the sheet and made a slight line in a waxy surface. The other hand produced a small vial that contained a black powder. This was shaken upon the flattened sheet of paper.

The substance was graphite. The fingers rubbed the black powder upon the smooth paper.

The result was immediate. It explained exactly what had happened. The surface of Inspector Burke's desk had been rubbed with wax. His writing had left invisible impressions, pressing through the paper upon which he had written.

The waxy surface, with its indentations, had been recorded on the thin sheet of paper. Now the graphite revealed a blackened scrawl, in reverse.

The hands raised the thin sheet, turned it over, and held it before the bright light. There, in plain writing was revealed the complete report written by Inspector Burke. Every detail of his interview with Doctor Heinrich Zerndorff was now plain to The Shadow.

The thin paper remained before the light. Hidden eyes were studying it. A mind in the darkness was remembering every detail.

The paper was crumpled and thrown away. The hands dropped to the table. They brought a pad and pencil into view.

The right hand began to write, forming beautiful letters that seemed to represent exact and carefully chosen thoughts. "Doctor Zerndorff," the hand wrote, "has chosen a wise and careful course. He has a keen brain. Yet he has accepted the obvious - through ignorance of certain facts.

"He has, as yet, received no tangible information from Detective Cardona. Even when he gains it - as he will - he may not realize what lies behind these events.

"He suspects a mastermind. He is correct. He suspects terrorism. There, he is incorrect."

An envelope appeared upon the table in place of the pad and paper. It bore the words: "Clippings from Clyde Burke."

The hands brought forth the clippings. Each was an account of a different explosion. Conspicuous in each was a list of those who had been killed.

A long, slender forefinger ran down the list of names in the first clipping, which bore the notation "Wall Street Explosion."

The finger stopped upon one name - that of Richard Pennypacker, who was listed as a broker, age forty-two.

Into view came a typed list, which was headed: "Men Concerned With Hubert Banks." In that list appeared the name of Richard Pennypacker; beneath it, the following notation: Stockbroker. Has known Banks seven years. Acquainted with important details concerning Banks'

financial status.

Next the hands touched a clipping that bore the notation "Grand Central Explosion." Here the finger found another victim's name - Glen Houghton, listed as an attorney, thirty-one years old. This name was checked.

The fingers slipped across the table to the typewritten list. There appeared the same name - Glen Houghton. Under it was the notation: Young lawyer a.s.sociated with the concern of Whitmeyer Barton, attorneys-at-law. This concern has handled legal affairs for Mr. Banks during the past twenty years. Houghton has handled certain details pertaining to Mr. Banks.

A third clipping was under survey. It bore the heading: "Subway Explosion." At the top of the list of victims was the name George V. Houston, clubman, age forty-eight.

The hands seemed to consult between themselves as they moved to the typewritten list. There, at the top, was the name George V. Houston. Information appeared beneath it: This man is a frequent visitor to the home of Hubert Banks. Was once engaged to Mathilda Banks, sister of Hubert Banks. Has known the family for many years.

The fourth clipping, which was marked, "Cla.s.sic Explosion," came in for a careful inspection while the hands remained motionless.

At length a pencil was taken by the right hand. It pa.s.sed over the names of the managing editor and the two reporters who had been killed. It stopped at the statement, "Unidentified Man, evidently a visitor to the newspaper office."

There the pencil placed a question mark. Now the clippings were brushed aside. Another envelope was drawn forth by the hands. It bore the words, "Report of Harry Vincent."

The hands unfolded a typewritten sheet taken from the envelope, and the hidden eyes read: Richard Pennypacker had his own office in the Tully Building. It was his custom to arrive at the office at nine o'clock. At ten, or shortly afterward, he would leave the office, carrying papers in his briefcase. He went to an office in the Stock Exchange.

He always followed the same route, and he happened to be on his customary path when the explosion occurred in Wall Street.

Beneath this appeared a second tabulation: Glen Houghton came into work from Mount Vernon. He always came through the Grand Central Station and stopped at one cigar stand to buy cigars for the day. It was his regular custom and he was evidently buying cigars when the explosion occurred.

Then came a third listing: George V. Houston lived at the New York Barge Club, opposite Central Park. He invariably came downtown at noon. He always took the subway at Columbus Circle. It was just after he entered the station that the explosion occurred, and he was one of the victims.

Three strange coincidences! Three freaks of fate that had brought men to their doom!

There were others who had died, but none of their names appeared in the typewritten list of those who had been a.s.sociated with Hubert Banks, except one, and it was not ignored.

Along with the listings of Pennypacker, Houghton, and Houston, appeared the name of Perry Warfield. It had its notation, as follows: Promoter. Has been engaged in various schemes with Hubert Banks. Went to Oklahoma on two occasions to investigate oil wells for Banks. Seems to be well off financially, and sees Banks frequently.

The name of Perry Warfield appeared upon the list supplied by Harry Vincent. But it bore no explanatory remarks. Evidently the long arm of coincidence had not stretched forth to seize this fourth man.

The hands of The Shadow became motionless. Only the changing glow of the fire opal on the third finger of the left hand gave signs of activity. The hands themselves seemed to be formed of molded wax.

Minutes ticked by. Then came a low, slight buzz from the corner of the room. The hands disappeared. A moment later, a whispered voice crept through the silence.

It was the first audible sound that had disturbed the silence since the light had clicked. A low conversation followed. The invisible man was talking over the telephone.

There was a click as the receiver was replaced. Then the hands, were back again at the table. They were writing, filling in the s.p.a.ce beneath the name of Perry Warfield, with letters that were as precise and as uniform as those of the typewriter: Burbank reports word from Vincent. Perry Warfield did not come from his home in Westfield today. He was taken suddenly ill. He will come tomorrow. He arrives at nine, every day and goes directly to theoffice of Barr Childs, in the Financial Building.

The hand hesitated. Then, in small letters it wrote these words: Before nine o'clock.

Each word was underscored by the pencil. The light clicked out.

Through the darkness of that pitch-black room came the sound of a hollow, whispered laugh. It was an uncanny noise - a mirthless murmur both forbidding and foreboding.

Its echoes resounded from the hidden walls and died away to nothingness. No other sound followed. The room was empty.

The Shadow had laughed, and now The Shadow was gone!

CHAPTER V. A HAND INTERVENES.

IT was eight o'clock in the morning. The first throng of early workers was still entering the Financial Building, Manhattan's newest skysc.r.a.per.

Beneath the towering monolith that raised its lofty spire eight hundred feet above the street, these people seemed less than pygmies. They came by hundreds, and were absorbed within the giant walls of the ma.s.sive structure.

The long row of elevators was working to capacity. A crowd of stenographers and businessmen were pushing their way into the waiting cars.

One elevator sped upward and made its first stop at the thirtieth floor. There it began to discharge its human freight.

It continued upward. At the forty-fourth floor, a single pa.s.senger stepped forth. The door slid shut behind him.

The man hesitated a moment, then walked along the corridor and stopped at an office which bore the number 4418. On the gla.s.s panel appeared the t.i.tle: Barr Childs. Investments.

The man reached in his coat pocket and removed a set of keys. He looked carefully about him and noted that he was alone in the corner of the corridor.

He was tall, immaculately clad in a tailor-made suit of dark blue. He appeared prosperous.

His most noticeable characteristic was his face. He was smooth-shaven and had a quiet, dignified expression. One would have hesitated to state that he was more than forty; yet his firmly molded features indicated that he might be much older.

The light that came through the gla.s.s-paneled door made his face seem masklike, as though his flat cheeks and aristocratic nose had been molded by some human artifice. As he gazed at the door before him, his eyes sparkled.

The visitor inserted a key in the lock. It was not the right key. He tried another; then a third. Each time, he was unsuccessful. He kept the third key in the lock and moved it back and forth with his thumb and forefinger. He was probing the lock as though he could feel its interior. His thumb and finger twisted. The lock clicked. The door opened.

The stranger entered the office and closed the door behind him.

A part.i.tion divided the office into two compartments. A gla.s.s-paneled door bore the word, "PRIVATE."

This door was locked. The visitor opened it with another key, finding his first attempt successful.

There was a closet in the inner office. This, too, was locked.

The keys that the stranger carried seemed gifted with a magic charm. Before a minute had elapsed, the door to the closet was open.

There were many articles in the small closet; boxes and piles of circular letters. With amazing rapidity, the stranger made a thorough inspection, removing various objects and replacing them exactly as they had been.

In less than five minutes he had completed his search. He locked the closet and looked around the room.

In the corner stood a typewriter table. There was no chair beside it. The man laughed softly. Evidently the table was not used regularly.

It was one of those tables that opened at the top, swinging the typewriter into position. It was locked, but this time the visitor did not resort to a key. He produced instead a tiny instrument which he pushed into the small lock.

Carefully and slowly, he swung the top of the typewriter table. The interior came into view. Instead of the typewriter, a square box appeared.

The stranger lifted the lid. He brought out a round object, larger than a bowling ball. Its top consisted of a small but complicated mechanism, made of polished bra.s.s.

It was a finely fashioned bomb, that rested on a slightly flattened bottom.

Long, thin fingers slid along the spherical surface. They discovered a close-fitted joint. The hands rested the bomb upon the table and carefully unscrewed the top.

The man laid this aside. It contained the detonator. The charge was within the thin sh.e.l.l of the spherical bomb. The visitor lifted the charge and removed it.

He replaced the top with its detonator, and put the empty bomb back in the box.

A bookcase, in another corner of the room, was set at an angle with a s.p.a.ce behind it. The man who had entered pulled the bookcase away from its position and placed the charge of the bomb behind it. Then he carefully arranged the bookcase as it had been before.

With a last glance about the room, he left and closed the door of the private office. He went into the corridor and disappeared. It was twenty-two minutes after eight.

At eight forty-five, a stenographer arrived and unlocked the door of the office. A few minutes after she had been seated at her desk in the outer office, a man entered. It was the same stranger who had been there before.

"Has Mr. Barr arrived yet?" he inquired. "Mr. Barr is in Chicago," the girl replied.

"Mr. Childs, then?"

"I expect him any minute. Will you wait?"

The man glanced at his watch. He thought for a few seconds; then decided to remain.

He sat in a chair in the outer office, and graciously accepted a newspaper which the girl offered him. He was reading when a short, stocky man arrived and briskly entered the office.

The newcomer had a fat face and a bristly mustache. He paid no attention to the man who was reading.

He unlocked the private door and went into the inner office.

The girl went over to the man who was waiting and asked his name. He gave her a card which bore the name Henry Arnaud. The girl carried it to the inner office.

There was a muted exclamation. The man with the bristly mustache burst from the outer office.

"Mr. Arnaud!" he exclaimed. "I am glad to see you - very glad to see you! I am George Childs!"

A slight smile appeared upon the chiseled features of the visitor. He had expected this reception.

The name of Henry Arnaud commanded attention in New York. There was only one Henry Arnaud; he was a multimillionaire, known for his eccentric investments.

"Come right in, sir, come right in!" continued Childs. He ushered his visitor into the inner office and gave him a chair beside the desk. He produced a box of corona cigars and Henry Arnaud accepted one.