level of the ground floor. Still moving downward through the metal cylinder, they reached an inner
doorway a dozen feet below. Professor Urlich pressed the barrier, and brought Ricordo into a dimly
lighted room.
LARRY RICORDO blinked and looked about him. The illumination came from indirect lights. It showed
that they stood within a large round pit, like the center of a coliseum. The analogy was more pronounced,
due to the presence of a balcony that circled entirely around the room.
A low rail, with metal posts supporting it, made the balcony a gallery. Here people could stand and view
the pit. Professor Urlich pointed across the room toward the front of the building.
"One enters the balcony from there," he explained. "Coming through the outer doors, one sees a door
ahead. It leads to the balcony. A very natural course to follow."
Urlich cackled as he spoke. Larry Ricordo felt uneasy. His feet were upon metal plates — a peculiarity he
had noticed on the first floor. But it was not this factor, nor the presence of the balcony, that troubled him
the most. The gang leader's eyes were attracted to the center of the room.
There he observed the strangest device that he had ever seen. It was a huge machine, different from
anything that Larry believed could exist. The odd device, which measured a dozen feet in each direction,
was mounted upon a heavy base, and was supported by posts fitted with rubber insulators. From it
extended insulated wires that disappeared into the metal floor.
Glistening wheels, flat disks of shiny metal, together with large glass tubes and other pieces of mechanism,
gained the gang leader's full attention. Ricordo noted a control box at the side of the machine.
"What is it?" he questioned, in an awed tone.
"An electric-ray device," responded Urlich, with a smile. "Designed to deliver death."
"You mean it's like the hot seat — up at the Big House — "
"If you are referring to the electric chair at Sing Sing prison, I can assure you that your analogy is partly
correct. The electric chair is designed, however, to kill only its occupant. This invention of mine will slay
at a distance."
"How far?"
"Within the radius of its electrified circles. At present, it will kill only those who are within the circular
corridors or who are close to this building. The metal plates receive the current. Watch."
The professor went to the control box. Ricordo stood beside him. Urlich swung a switch. The big
machine began to crackle. Long, snapping flashes of miniature lightning jumped back and forth across the
top of the complicated machine.
Ricordo, nervy though he was, shrank away and stared at myriad sparks that flashed along the balcony
rail.
Professor Urlich swung back the switch. His cackling laugh replaced the buzz of the machine. Larry
Ricordo sniffed the ozone with which the atmosphere was now charged.
"When I first designed the machine," explained the professor, "I had a small platform mounted beside it.
The only sphere of influence was the floor on which we are now standing. I placed cats — dogs— other
animals upon this floor. They were killed instantly.
"Then I extended the zones. The balcony — the outer corridor— finally the portico. These colored
lights" — the speaker pointed to a row of unilluminated incandescents—"are for each zone. They tell
which portions of the ground floor happen to be occupied."
"But we are standing on metal," objected Ricordo. "You say you used this floor. Why are we safe?"
"Each zone is separate," explained the professor. "There are strips of insulation between. When I
extended my experiments to the outer circles, I merely disconnected this one."
"You have three circles now — "
"Yes, and I shall tell you why. I learned that each circle threw a killing power outside its boundaries. The
greater the circle, the greater the effect. It was only a few feet at first; now the sphere of influence extends
a dozen yards beyond this building!
"With a machine much larger than this one; with a circle a thousand feet in diameter, I estimate that I
could slay all persons within a radius of one mile!"
"It would be a big job to rig up an arrangement like that."
"Of course. But in the meantime" — the scientist's eyes gleamed wickedly— "this building is completely
"You mean if The Shadow should try to attack you!"
"Yes. He would come to his certain doom. I have other lights upstairs. We watch them constantly. That is
why I have said that I would welcome a visit from The Shadow. But do not look for it, Ricordo.
"Sanoja is ready for us now. I shall view the device that he has made for my approval. If it is exactly as
he designed it, we shall be ready to lure The Shadow to another trap of doom."
THE professor wheeled and walked back toward the cylinder which housed the spiral stairway. Larry
Ricordo shuddered. Hardened criminal that he was, the amazing schemes of death designed by Professor
Folcroft Urlich frightened him.
One last look at the glittering electric-ray machine; then Ricordo ascended at the professor's heels. Until
now the gang leader had not realized the stupendous power of dealing death that Folcroft Urlich
possessed.
Doom to The Shadow! It would be a certainty should the black-garbed visitant attempt to penetrate the
heart of Professor Urlich's domain. Yet Larry Ricordo still digested the scientist's final words.
A new trap for The Shadow. Another subtle scheme in the making. Again, it would be Ricordo's part to
lay the snare that Professor Urlich had designed.
The gang leader grinned. He was confident now. He had a hunch that The Shadow would never even
learn of this strange place where Professor Urlich lived.
Some subtle device would soon accomplish an effective result against the one being who blocked the
scheme of widespread murder.
CHAPTER X. CARDONA INTERPOSES
EVENING had arrived. Detective Joe Cardona was seated at his desk. He was studying reports on the
explosion which had occurred at the apartment of J. Wesley Barnsworth. He also had a pile of data
referring to the episode at Alfred Sartain's penthouse.
Completing his survey, Cardona arose with a satisfied smile. He went from the office and entered another
room where he accosted a bluff-faced man who was sitting at a desk. This was Inspector Timothy Klein.
"Hello, inspector," greeted the detective. "Thought I'd better let you know that I'm going out on this
explosion case. I may get somewhere with it, to-night."
"You'd better, Joe," responded Klein. "You know how boiled up the police commissioner is about it.
He'll have you on the carpet first thing you know."
"I've got a hunch it's linked with the trouble that took place up at Sartain's."
"A hunch?" Klein snorted. "That's no hunch, Joe. The commissioner has the same idea. That's why he's
steamed. He knows both of those men personally."
"I know all about that," answered Cardona. "I also know that the commissioner is keeping quiet only
because neither of his friends were killed. He's got a hunch — like I have — that there's going to be a third
mess soon."
"If there is," warned Klein, "you'll be up against it, Joe. If the same people have tried to kill a big
millionaire and an important man in Wall Street, it's bad enough. It lea
ves it up to you to block them
before they murder somebody."
Joe Cardona smiled. He understood Klein's apprehensions. He knew that the inspector had talked with
Commissioner Ralph Weston. Joe also knew that he, himself, rated highly with the commissioner except
when failure was involved. That was the secret of Cardona's smile. The detective intended to get results
to-night.
"You say that the commissioner has my hunch," remarked Cardona. "Maybe he has but the commissioner
don't know what I know. I'm going after a bird that may sing a song when I get him. I've been looking for
him, and I've spotted him."
"You mean you know who is responsible?"
"I don't say that. I merely believe I can find a man that's mixed in it."
"Why haven't you grabbed him? Who is he?"
"LISTEN to me, inspector," argued Cardona quietly. "When we landed at Sartain's penthouse, we found
a dead man whom we identified. Duster Brooks — a smart crook. He had been working as Sartain's
butler. He tried to kill Hunnefield, the millionaire's secretary.
"What was the logical answer? I'll tell you. It looked like Duster's job. He didn't get away with it. Two of
his men were dead. Hunnefield said there were others. Naturally, we wanted to get them; but it wasn't a
murder charge.
"I looked over the records. I found out that Duster Brooks was tied up with another gunman named Slips
Harbeck. There was a chance of a connection. So I put a stool pigeon out to look for Slips Harbeck. He
found him yesterday. Slips is hanging around a joint called Red Mike's."
"You let him stay there?"
"Sure. We had nothing on him. I was looking for other evidence before I grabbed him. Just wanted to
know where he was — that was all. I figured the trouble was all over. I couldn't implicate Slips Harbeck.
"Then — bang! Along comes this explosion at Barnsworth's. That told me that Duster Brooks wasn't the
fellow in back of all the trouble. He was just working for some one else. Who pulled the job at
Barnsworth's? How was it done? I don't know. But I figure that maybe Slips Harbeck does."
"Very good, Joe," commended the inspector. "It's too bad you don't have some evidence. You could
grab this fellow Harbeck and make him talk."
"I'll get evidence," stated Cardona grimly. "The stool is watching Slips Harbeck like a hawk. More than
that, I'm going to be around Red Mike's tonight. I figure that there may be another job in the offing.
That's why I'm having Slips watched. If he starts out to make trouble, I'll be in on the ground floor."
"You're using your head, Joe," was Klein's comment. "That's the ticket. Get something on Harbeck. Then
he'll have to talk."
"I'll do more than that," returned Cardona. "I don't figure Harbeck as the big shot in this game. I think
he's the same as Duster Brooks— a little guy. I'm going to land the topnotcher!"
With that final promise, Joe Cardona stalked from the office, leaving Inspector Timothy Klein tapping the
desk in thoughtful satisfaction.
JOE CARDONA had gained the right information when he had learned that Slips Harbeck was hanging
around Red Mike's. An hour after the detective had talked with the inspector Slips was at his
accustomed table in the speakeasy. He was cautiously watching a man near the end of the room. Cliff
Marsland, too, was there again, tonight.
Little did Slips realize that there was a third player in the game. A furtive, rat-faced prowler of the
underworld was also in evidence. This was "Gawky" Tyson, a dopy character who was no more than a
lesser pawn in the affairs of gangdom.
No one ever bothered the pitiful creature who now sat within the door of Red Mike's speakeasy. But
Gawky Tyson's life would have been in jeopardy had gunmen realized the role which he played. Gawky
Tyson was Joe Cardona's stool.
To-night, Gawky was watching Slips Harbeck closely, and with confidence. For the stool pigeon had
received assurance from his boss, Joe Cardona, that detectives would be in the offing. He was to learn
what Slips Harbeck intended to do, and to give the tip-off in case trouble was brewing.
Red Mike came sauntering through the speakeasy to talk to Slips Harbeck. His message was the usual
one. Slips was wanted on the telephone.
With a grin, Slips went to the inner room. He heard the voice across the wire. He performed his former
ruse — that of letting the door rest ajar.
Once again, Slips Harbeck was getting instructions which he was not to conceal. But to-night, there were
two listeners on the other side of the door— men who paid no attention to each other. One was Cliff
Marsland; the second was Gawky Tyson.
"Sure thing." Slips was talking in a tone that carried, despite its feigned caution. "Yeah… Yeah… I won't
slip up to-night… One-man job, eh? A little later? O.K… Office of Gardner Joyce… 2020 Sharon
Building… Wait till I get that straight… Signed contract in the desk drawer… Inner office… Grab it and
wait there for a phone call… That'll be you calling?… No? What's the idea?… I say 'Nothing doing.'… I
see; if I want to have this straight. You've got a fellow fixed to call that number. Right?… Then I just tell
him O.K., if I've found the contract. If I haven't, I say 'Nothing doing'… I see; if I haven't found it, it's
because the contract must be in the safe. I wait there then… Yes, until you show up to crack that box…
Right-o. I'll be ready to grab the phone as soon as the guy calls up… Bring you there if I need you…"
Just as Slips Harbeck sauntered from the inner room, Cliff Marsland was reaching the outer door of the
speakeasy. Slips caught a glimpse of the disappearing figure. He grinned.
There was no doubt about it now; Cliff was an agent of The Shadow. He had probably left to relay his
information to his mysterious chief.
Once again, Slips had bluffed. He was not to go to that office to-night. The whole affair was a blind. Slips
could not figure the game; but that did not worry him. He decided to follow his previous policy; to wait a
few minutes; then leave the speakeasy and double back into his upstairs quarters.
WHILE Slips Harbeck was planning thus, Gawky Tyson arose and left Red Mike's. The furtive little
gangster was accosted in the darkness before he had gone a dozen yards. He saw three men looming
before him. One was Joe Cardona.
"What did you get?" demanded the sleuth, in an undertone.
In quick, breathless tones, the stool pigeon gave the information that he had received. Joe Cardona
grunted and spoke to his men.
"Lay here, boys," he told them. "Grab this bird Harbeck as soon as he comes out. You hang across the
street, Gawky. Give the whistle when Slips shows up. Then beat it. I don't want you around."
"I don't want to be around," yapped Gawky. "I'll scram quick enough. They'd get me if they knew I was
tippin' youse guys off."
Cardona stood a short distance away while his men moved close to the speakeasy. The ace detective
was thinking. He had two objectives to-night. One was the capture of Slips Harbeck; the other was the
spoiling of crime. By taking Slips, he was eliminating the gangster's visit to Gardner Joyce's office.
As Cardona mulled over the situation, he began to take the natural reaction to the details which Gawky
Tyson had obtained. Slips Harbeck had a mission to-night. He was to enter Joyce's office and there
await a telephone call
.
If no answer came, the call would probably be repeated. But that would not go on indefinitely. The word
would get to Slips Harbeck's chief that the gangster was not there.
Cardona specifically remembered that Gawky had said the call would come from some one whom Slips
did not know. "O.K." would be the answer, meaning that the job was done. "Nothing doing" would
signify that the contract had not been found.
Then what? Harbeck's chief would arrive! If the police were there when he landed, he could be captured
on the ground! This was opportunity.
Joe Cardona quickly formulated his plan. He needed no help right away. His two men must remain here
to grab Slips Harbeck. That was essential to Cardona's present scheme. It would obviate the possibility
of communication between Slips and the man above.
The detective turned and walked rapidly along the street. His mind was set. He would visit Gardner
Joyce's office in the Sharon Building. He would receive the message and summon Harbeck's chief. There
would be time then to call other detectives and have them stationed outside the office building. They
could follow the visitor in; Joe himself could make the capture.
Cardona reached a side street where his police car was parked. He leaped to the wheel and drove
away. He was confident that his men would do the work at Red Mike's. In this belief, Cardona was right.
AT that very moment, Slips Harbeck was sauntering from the speakeasy. The gangster never reached the
alley where he intended to go. The detectives dropped upon him as they heard Gawky Tyson's low
whistle.
Slips fell under the attack. His mad swing brought a stunning blow to the back of his head. The detectives
dragged him away.
Slips Harbeck was in the hands of the police. No one was the wiser. He was being taken to
headquarters. It was there that Joe Cardona expected to find him later on. The ace detective had planned
well.
Cardona was heading for another goal, satisfied that all would be well tonight. He thought that he knew
all the plans involved. He, alone, could know the situation that existed.
Little did Cardona suspect that Slips Harbeck's plans had been purposely broadcast for listening ears;