'Still, I am working - with a single hope.'
'What is that?' Zerndorff asked.
'That he shall make a move to trap me. I, too, am playing a lone hand now. It is because of his craftiness that I may succeed.'
'How so?'
'He knows that I will go to any measure to defeat him at the earliest possible moment. I am the attacker.
I must move. He can receive my attack when I am at a great disadvantage. That is one reason why I have come to you.' Gage's tone was deeply earnest now.
'To me, yes?'
'To you, Doctor Zerndorff, because at any time, I may meet with unexpected danger that will result in death. Remember all that I have told you, because it will be your fight later on, if I meet with failure now!'
'There is one thing,' declared Doctor Zerndorff thoughtfully, 'that makes me feel so strongly that this man is active in these bombings. Perhaps it will be a clue, yes. I shall tell you.'
There was a definite assurance in the criminologist's tone. Despite Gage's weariness, his eyes sparkled.
'It is about these bombs,' continued Doctor Zerndorff. 'I have not yet discovered what it is that has made them operate.
'It is not the fuse. It is not the timing. It is not the radio.'
'You have constructed duplicate bombs?'
'Yes. But it is of no use. I thought that the radio was the method. I have found the wonderful radio operation for bombs, yes. But it is not the way. Not with the bomb that Vervick has made.
'There is something that is missing! Something which I cannot understand! It must be that there is some sensitive object, of an active agent, like radium, that has discharged those bombs!
'In my search, I have sought many places. I have found that special bits of delicate machinery were bought at certain places. They were ordered sent away.
'The police have investigated, but have learned nothing. They have been satisfied because they have found the extra pieces in the shop of this man Vervick. That has been all they have needed.'
The German arose and went to a desk in the corner of the room. He brought out a folded sheet of paper and handed it to Gage.
'Here are the lists that I have made. Perhaps, through these, you may find the clue to The Master. It is probable that he has bought these things and has given them to Vervick. You think so?'
'It is highly probable, doctor!' Gage was enthusiastic. 'This may be exactly what I need! After three weeks of hopeless effort, I am anxious to find any clue!'
Doctor Zerndorff bowed.
'Let me say one thing,' he remarked. 'You must be careful. Remember' - he tapped his forehead - 'you are to fight against the brain. The man you seek is waiting. I should not like to see you lose your life. I can see the great dangers before you!'
'Dangers. Yes.' Clifford Gage smiled wanly. 'But there is one danger that I do not fear.'
'What is that?'
'Bombings!' Clifford Gage arose and walked to the door. 'I won't be blown up - that much is certain.
Not for a while, at least. That work is ended - until these convicted men have been electrocuted.
'After that - well, doctor, I advise you to learn even more than you now know about bombs. You will need to know everything!'
With that, Clifford Gage was gone. The door closed behind him almost before Doctor Zerndorff realized it. The criminologist went to the window. He turned out the lamp beside him and stood staring into the street.
No one appeared there. A long, black shadow flitted beneath the glare of an electric light. Doctor Zerndorff's keen eyes sought to find a form beside it. But no one was visible.
Silently, mysteriously, Clifford Gage had vanished into the night. Once again he had assumed the unknown personality of the strange being called The Shadow.
Doctor Zerndorff remained beside the upstairs window. Staring and motionless, he waited while long minutes went by, until, at last, he heard a knock at the door of his room.
Otto entered.
'You have not seen anyone downstairs?' questioned Doctor Zerndorff.
'No, Herr Doktor,' replied Otto.
Doctor Zerndorff shook his head.
'It is wonderful, yes,' he muttered. 'They call him The Shadow. He is the man that seems like he is of the night. He brings me the amazement!'
CHAPTER XVIII. MYSTERY HOUSE
IN uptown Manhattan stood an old, deserted house. Thick bars and gratings protected its windows, even up to the third floor.
The house had become desolate, specterlike, even before the owner's death, a few years before.
Pedestrians shuddered and increased their pace as they passed the sinister mansion on dark nights.
No one would openly declare the place was haunted, yet the few who had rented it found some excuse to break their lease.
The new owners shrugged and left the place as it was, hoping that some strange eccentric character, like the former owner, might rent the place.
One tenant at last rented it, at a ridiculously low figure. He made all arrangements by phone and letter, apparently not caring to show himself.
The owners did not ask him why he chose to live in such a gloomy place. He had paid the year's rent in advance; that was all they wanted.
Since he moved in with his furniture, no one had seen him either enter or leave the house.
A few months after the new tenant had moved in, a tall, dignified man called at the office of the company which had taken furniture into the weird house. At the man's request the movers told him the exact date of moving the furniture, and also the address from which they had taken the furniture.
That night, the same man might have been seen near the house. He wore dark clothing, and when he walked down the street he seemed to melt into the blackness of the houses across the way.
This continued for two nights. So silently and invisibly was the man's mission accomplished that not even the watchman in a nearby factory noticed the vigil that was being kept.
On the third night, an automobile passed along the street before the house. The red reflection of its taillight revealed a momentary shadow on the paved street. That was the only indication of a person's presence.
Shortly afterward, there was a definite motion beside the darkened wall near the rear of the mysterious house. A vague shape rose from the blackness.
Invisible hands engaged the fastenings of the bars on a ground-floor window. Someone was working, cautiously striving to remove the fastening that seemed as permanent as the wall itself.
Many minutes elapsed; there was no sound other than a swishing noise that was almost inaudible. Then the entire grating came away. After that, the window opened noiselessly. A human form glided through the space.
The glare of a flashlight appeared within the dark house. The light could not be seen outside, for it was focused on the floor and its luminous circle was very small. The light moved through the hallway as though floating in the air.
Not a sound followed it. At last it rested upon a door that was fitted with a lock.
A hand holding a ring of keys came into the circle of light, the lock clicked, and the door opened outward. The light came on. At first it was a tiny circle on the floor. Then came the powerful beam of a larger light that revealed the full interior of the apartment.
The room was draped with pleated black curtains. It was carpeted with a dark covering.
It was the exact counterpart of that room where Howard Jennings had received his last instructions, and in which Harry Vincent had lost his reason!
It was the lair of The Black Master!
