Doc protected his glass sash from flying fragments by holding it partially under his coat. Plaster dust rolled into the street and surrounded him with a choking gray fog.
Monk and the others charged into view. Monk’s homely face became starkly woebegone as he discovered Lea Aster was not with Doc.
“What did you find, Doc?”
“There was nobody in the place.”
“But what caused that explosion?”
“I left a firecracker behind.”
Monk snorted. “No firecracker could make a blast like that!”
“It didn’t,” Doc explained. “It merely moved your secretary’s wristwatch which was lying on the floor. 2 small wires — almost too fine for the eye to see — were connected to the watch and were broken when it was moved. Breaking them exploded a bomb in the basement.”
“Then it was a trap!” Monk groaned.
“Right.”
The men stared curiously at the pane of glass which Doc was handling with such care, wondering of what importance it could be.
The Bronze Man gave them no time for questioning. He hurried along the street until he encountered a cruising taxi.
En route to his skyscraper Headquarters, he explained a little further about what he had found in the deserted tenement.
“Buttons and his gang fled — taking the girl — probably within a few moments after they tricked her into giving us the decoying phone call,” he finished.
Reaching his office, Doc placed the glass pane on the inlaid table, then entered the Laboratory. He returned with a device not unlike a large edition of a box camera.
Monk looked at this mechanism… then at the glass.
“Uh oh!” he ejaculated. “I catch on!”
Doc drew the shades, producing gloom in the office. He plugged a flexible cord which ran from the camera-like box into an electric outlet. He pointed the dark glass “eye” of the apparatus at the window sash.
A startling thing happened.
Upon the glass, where nothing had been before, there suddenly appeared, uncannily, glowing blue letters. It was as though some fantastic magic had operated.
To Doc’s men, the phenomenon was an old one. They knew the explanation.
The camera-like box projected invisible rays. Under these rays, many substances “glow” or fluoresce. Capitalizing upon this latter quality, Doc had perfected a chalk which left no writing visible to the naked eye but which sprang out in this vivid blue under the ultraviolet beam.
Each of Doc’s men carried this chalk for use in penning secret messages. Although it worked most effectively on glass, it could also be used to write on practically any smooth surface. The chalk itself could be readily concealed.
Doc had even manufactured a hard variety of the strange crayon which could be made into efficient buttons.
No doubt it was with such a button that Monk’s secretary had written the message upon the glass!
Gathering close, Doc and his men translated the communication. It had been written in haste but was nonetheless perfectly legible. Lea Aster was an excellent penwoman.
It read:
I hope you find this message, Mr. Savage. Here is what I have overheard:
My captors are working under a leader in Arizona. They have a secret hide-out in Red Skull Canyon in Arizona. This place — marked by 4 lights at night — is situated some miles downstream from the skull-like formation of red rock from which the canyon gets its name. I heard them telling Whitey — one of their number — where the place is. Whitey evidently intends to fly them there. They have negotiated for the purchase of a plane at the Star airport.
I heard the Mountain Desert Construction Co. mentioned as well as the names of 3 men. Nate Raff, Richard O’Melia, and Ossip Keller. I could not make out what was being said, except that some peril threatens one or more of these 3 men. But the documents I filched…
The script ended with that. Doc turned off the ultraviolet lantern and the pane of glass instantly became blank.
“I move we vote my secretary a medal!” Monk grinned. “She’s given us a line on the secret hideout of the gang.”
“Further than that, she has proved the connection between the Mountain Desert concern and our enemies,” Doc added.
Monk’s elation was only temporary. He sank again into the depths of gloom.
So marked was his concern that Ham dared not make any of his usual biting remarks — something that rarely occurred. When Ham laid off Monk, it was an event!
“How are we gonna find the girl?” Monk demanded mournfully.
His furry fists knotted and unknotted. His eyes roved the office as if reluctant to remain focused for long on any one object. His gaze fixed absently on the window.
Atop the skyscraper from which Doc’s office could be seen, Buttons Zortell ducked hastily from the nickel-in-a-slot telescope through which he had been peering. He made the move instinctively before he realized he was too far distant to be discovered.
Not daring to remain in the vicinity of the tenement where he had planted the bomb, Buttons had come to the skyscraper observation tower. He was disgusted beyond measure that Doc and the others had appeared! Uneasiness had settled upon him too.
“Blazes!” he groaned. “How’d that bomb miss gettin’ them rannies?”
“Maybe a packrat tried to carry off the wristwatch and fired the nitro,” suggested one of Buttons’s men who had accompanied him.
“I don’t think they have packrats in this neck-of-the-woods,” Buttons grunted. “Don’t make no difference how it happened, anyhow. We fell down on the job!”
“The Boss ain’t gonna like this.”
“What about me? D’you think I’m happy!” Buttons snapped angrily. “We done our best, didn’t we?”
The other changed the subject. He always became a little afraid of Buttons when the man flew into a rage. Buttons was known to have killed more than once while angry.
“What was Savage lookin’ at on that hunk of glass?”
“Search me,” Buttons grumbled, his wrath subsiding somewhat. “That’s kinda worryin’ me. This ain’t an ordinary spread of gents we’re up against. I’m beginnin’ to think the stuff the newspapers told me about Doc Savage wasn’t so much ‘hooey’ as I thought.”
“The Boss said to clear outa town if the bombin’ failed,” his hireling reminded.
“Don’t think we ain’t gonna do it, either!” Buttons grunted. “Back in them Red Skull brakes, I’ll stake myself against any fightin’ men! Here in the city, I ain’t so sure of myself.”
“What about the girl?”
“We’ll take her along, of course.”
The pair hurried down a winding staircase to the elevator landing.
Monk had observed nothing of the little tableau on the distant skyscraper observation tower. He moved his tired gaze to his companions.
“I wonder what can be back of all this,” he ruminated. “From the ending of my secretary’s message, I believe she had just started to tell us what was in the documents she lifted from Buttons. She must have been interrupted.”
Doc Savage was thumbing through a telephone directory and did not look up.
“What are you hunting, Doc?” Ham asked.
“Miss Aster mentioned that the gang had purchased a plane at the Star airport,” Doc told him.
“Huh!” Monk exploded. “I overlooked that angle!”
Doc found the flying field number and put in a call. He got no answer. A second try a few moments later was also fruitless.
“The drome isn’t far out,” he declared. “We’ll drive.”
Doc kept a number of automobiles in a special garage in the basement of the gigantic building. Outside of the skyscraper employees, very few persons knew of the existence of this garage. A large elevator lifted the machines to the street.
Doc selected a touring car of moderate size and plain color, a machine that was inconspicuous. Although presenting no quality out of the ordinary to a casual observer, the chassis of the vehicle possessed unusual strength and the engine developed an excess of 200 horsepower.
The machine whisked them through traffic, over one of the bridges which give access to Manhattan, and out a busy boulevard. Within less than half-an-hour, Doc guided the car upon the tarmac of the Star airport.
A small drome, it apparently did little business. A few rusty metal hangars and a ramshackle board office comprised the equipment.
No one was in sight.
But in the shack of an office, they found an unconscious man. He had been felled by a blow upon the temple. It took Doc 10 minutes to revive him and obtain his story.
“I’m the manager,” the man mumbled, still dazed. “Yeah, I sold some guys a plane. An 8-passenger, single-motored green metal monoplane.”
“Who struck you?”
“The guys I sold the ship to. They showed up about 20 minutes ago. They was draggin’ a girl with ‘em. She was a blonde… a real peach! It looked like she was in trouble and I started to interfere. One of the guys popped me on the head with a six-shooter as big as a cannon!”
Doc and his men exchanged glances.
“They took off with Lea Aster, it’s certain,” Monk muttered. “I’m bettin they’re headed for Arizona!”
“Come,” Doc clipped.
He made swiftly for the touring car. The engine started moaning the instant he was under the wheel. The others piled in as the machine whipped into motion.
“I reckon we’re bound for Arizona, huh?” Monk questioned hopefully.
“You said it,” Doc told him grimly.