THE MICHIGAN CLEW
The concussion of the explosive within the tunnel caused the earth to quake until Doc all but lost his balance, despite his tremendous agility.
Rubble was blown from the mouth of the tunnel with sufficient force to carry many yards; the stuff blasted in the direction of Hack and his companions.
As the hail of débris struck, the pair stopped shooting. Either a rock broke their light, or they switched it off, for its glitter vanished.
Doc Savage, with Long Tom’s manacled frame across his tremendous shoulders, pitched through the night. The hill into which the tunnel penetrated was steep. There was danger of the explosion sliding its top down upon them.
The cataclysmic force of the detonation seemed to lift the entire hilltop. Great cracks split and gaped open. Trees upset. Rocks and soil spurted upward, as explosion-gas escaped through the rents.
The hilltop settled, causing great gushes of dust. The tunnel mouth closed completely. The reverberations of the blast whooped and thumped, like unseen giants fighting each other, until they weakened away into nothingness.
The monster within the van, whatever might be its nature, certainly had perished in that blast, buried under hundreds of tons of stone, shale and earth.
A more effective tomb would be hard to conceive.
Doc Savage lowered Long Tom. By way of proof that the bronze man’s earlier feat of snapping the handcuff links was no freak, the linkage securing Long Tom’s wrists and ankles now parted easily under Doc’s great corded hands.
“How’d you get here, Doc?” Long Tom demanded.
“Renny picked me up in the gyro,” Doc explained. “Using the ultra-violet light, we managed to locate the van. We followed the thing, and lost sight of it when it went into the tunnel. I dropped down by parachute to see what had happened.”
“The steel-haired girl was taken off the van a few hundred yards back,” Long Tom offered.
With the ghostly abruptness as of a bronze specter, Doc Savage vanished into the night. He made directly for the spot from which the shots had been fired.
* * * *
Dust rolled in choking waves. The cloud banks that had made the sunset so abrupt had gorged the sky with their sooty mass. Dust and clouds, combined, made the night very dark.
Far overhead, Doc could hear faint hissing noises. They might have been made by the wind. Actually, they were the sound of the silent motors which propelled Renny’s gyro and the larger speed plane in which Johnny and the others rode. Johnny had landed and picked up Monk, Ham, and fat Griswold Rock.
Griswold Rock had not been enthusiastic about taking to the air, having admitted a fear of airplanes.
Doc Savage, using his fabulously sensitive ears and nostrils, ascertained that the gunmen had fled. He increased his speed. The fleeing pair had taken to the disused road which approached the mine mouth.
Doc, catching faint sounds of their flight, ran faster. His quarry had turned off the road into a very level field. Doc caught a faint tang of gasoline.
Out of his pocket came a small boxlike device. It was a radio transmitter-receiver, designed for an ultra degree in portability. He clicked the switches.
“Renny! Johnny!” he called.
“I’m on,” Renny’s thumping tones replied.
“Me, too,” added Johnny’s more scholastic voice.
“Toss out flares,” Doc commanded. “I think these fellows have a plane waiting down here. There’s a smell of gasoline in the air.”
That this deduction was correct was quickly verified. A plane motor whooped into life out on the level field.
High overhead, almost against the black flanks of the clouds, a light appeared. Rivaling the sun in brightness, it bathed the earth in glittering white, causing every grass blade to stand out. It was the flare which Doc had ordered. It sank slowly, lowered by a small parachute. Its intensity seemed to increase as it eased down in the sky.
Doc caught sight of the plane. It was a low-wing cabin job, and it looked fast.
Caldwell himself was inside the glass enclosed cockpit, handling the controls.
* * * *
Giving his engine no time to warm up, Caldwell fed the cylinders gas. The low-winged ship picked up its tail and scudded across the field.
In the calcium flare, Doc Savage discerned a feminine face jammed to the cabin windows. The steel-haired Jean Morris apparently was still a prisoner.
The plane vaulted off.
Above, Renny’s gyro and Johnny’s speed ship came spiraling down to attack.
Doc, directing the affair by radio, commanded, “Watch it, you fellows! The girl is in their plane.”
His warning was hardly necessary, however. Caldwell’s plane climbed with astonishing speed. To the west, clouds hung very low. The craft made for these. As it banked, Doc caught a glimpse of the license numerals in the flare glitter. He made note of the number, fixing the figures in his retentive memory.
It dived into the vapor bank and was lost to sight before it could be overhauled.
“Holy cow!” came Renny’s disgusted ejaculation from the gyro. “We haven’t got a chance of trailing them through these clouds.”
Renny’s gyro and Johnny’s faster bus swung in great circles, searching. Johnny even climbed the ship above the clouds, where there was moonlight. No trace did they discern of Caldwell’s aerial conveyance.
It had made an escape.
Johnny tossed out another flare, banked down and leveled off. There was some bouncing to his landing, but considering the landing speed of his ship, it was expert.
Long Tom had joined Doc. He watched Johnny get out of the plane.
“Johnny sure looks like the advance agent for a famine,” the electrical wizard remarked.
This described Johnny’s appearance accurately. He was extremely tall, and thinner than it seemed possible for any man to be. Dangling by a ribbon from his left lapel was a monocle—actually a powerful magnifier.
Griswold Rock scrambled out of the plane after the gaunt Johnny. Rock’s fatty face was white as dough, and was dripping perspiration. His hands trembled.
“I hate airplanes!” he wailed. “They always scare me.”
So that only Doc could hear, Long Tom remarked, “Everything seems to scare that guy!”
Renny now dropped his gyro lightly upon the field. Alighting, he fanned a huge fist in the general direction of the sky.
“Holy cow!” he rumbled. “How’re we going to trail ’em?”
“I can help out,” Long Tom said shortly. “I overheard them talking. They’ve got a hangout somewhere near Trapper Lake, Michigan. They were going to head for that spot.”
Griswold Rock held up plump, soft hands in a gesture of incredulity.
“Surely you’re not going to follow them!” he ejaculated. “Don’t you see that they are too dangerous to monkey with?”
Big-fisted Renny answered this. “Cracking down on guys like them is what we do for a living.”
* * * *
Griswold Rock shuddered, and all of his fat jounced and shook.
“I’m a coward!” he wailed. “Don’t count on me. I wish I could go to South America or some place until this is all over.”
Doc Savage began outlining his intended course of action.
“Renny,” he addressed the big-fisted engineer, “your knowledge of engineering includes dope on excavating methods. You probably know where machinery and men can be gotten in a hurry.”
Renny nodded and looked gloomy. The gloomy expression was deceptive. The more somber Renny looked the more he was probably enjoying himself.
“You will start excavation on the closed mine tunnel,” Doc told him. “Dig in and see what the monster was.”
“O. K.,” Renny said.
Doc Savage now addressed Ham, whose specialty was law. “You go over the records and recent legal papers of Mr. Rock’s Timberland Line railway. See if you can unearth anything of value. Mr. Rock will want to know what kind of papers he has been forced to sign recently, anyway.”
Fat Griswold Rock suddenly shook his fist violently at the sky where the plane of their enemies had lost itself. Color came into his flabby cheeks.
“You don’t need to look for the chief villain!” he yelled. “It’s that chemist, Pere Teston.”
For the briefest moment it seemed that Doc Savage’s weird trilling note was audible. His five men showed marked interest, for the sound indicated that the big bronze man had just heard something which he considered important.
“Chemist!” Doc repeated. “You neglected to state that he was a chemist.”
“Did I?” Griswold Rock clucked regretfully. “I was excited. I suppose I left out that detail. It’s not important, anyway. He was a half-baked chemist.”
“Half-baked!”
“I mean he had crackpot ideas. He was a nut on scientific farming. He was always going around talking about increasing the efficiency of farm animals. He got so goofy about the idea that he was worthless to my railroad as an employee, so we fired him.”
“Along just what lines did he hope to increase the efficiency of farm animals?” Doc asked pointedly.
“I don’t know.” The fat man shrugged. “I didn’t pay much attention to that. He was just another employee. Now, though, I wish I’d kept my eye on him.”
Doc asked several other questions. These merely developed the fact that Griswold Rock had no more information of importance to divulge.
“I don’t want to go to Michigan with you!” said the fat man.
“We have no intention of forcing you into danger,” Doc told him. “You can remain here in New York, if you prefer.”
“The rest of us are going to Michigan?” Long Tom demanded.
“We are,” Doc told him.