Coffer dams erected above-and-below the main construction held back the water. Big pumps kept the space between the coffers fairly dry. The river was diverted through tunnels in either wall of the chasm. These would later serve to carry water to the powerhouses.
On cables slung across the canyon traveled basket-like cars sometimes called “storks”. The nickname probably came from the dizzy rides they offered. They had been erected to ferry the workmen from the opposite side at the hour when shift changed.
Near by, power shovels were mucking rock into trucks. A bit farther on, scalers were working on the cliff with jack-hammers and drills, setting powder shots. This work had to do with opening a road which was to cross the dam.
Doc moved in search of Monk.
A caterpillar tractor with a “bulldozer” on the front and a “cowdozer” on the rear was pushing loose rock into piles for the mucking shovels.
Over the whole scene rolled the rattle and clank and scream of machinery, the whine of motors, the chugging of trucks, the clattery gurgle of concrete, and the shouts of bosses. Dust squirmed in clouds.
The heat was terrific! Practically none of the workmen wore shirts and the Sun had burned them brown as Indians.
Monk was slung down the dam face. With the aid of 2 “scalers” (i.e., men who had formerly been circus acrobats), he was sinking small holes into the concrete and taking samples. Later the holes would be filled with grout under pressure.
“Everything seems to be okay so far,” he reported.
Monk’s assigned job was to ascertain whether any faulty material had gone into construction — material which might later cause the great barrier to give way. His ability as a chemist fitted him for this work.
High up on the abysmal walls, Doc could discern Johnny. The lanky geologist was moving about like a “granddaddy-long-legs” spider. He carried his spectacles with the magnifying left lens in one hand and a prospector’s hammer in the other. A bag for rock specimens was slung over his shoulder and bounced around as he climbed the cliff.
Johnny was seeking the cause of mysterious rock-slides which had not only destroyed valuable machinery at various times but also had crushed 4 workmen to death. Apparently solid areas of stone had a habit of giving away for no explainable reason, according to reports.
What caused this, Johnny was pretty certain to learn. Few men knew more about the structure of the Earth than did Johnny.
Doc took an elevator down to the rear of the dam and made for the powerhouses. These were 2 in number — one on each side of the river — and were only partially built. Installation of the turbines and generators had yet to be attended to.
The electrical wizard Long Tom had taken charge of this phase of the work. Doc found him in the left-hand powerhouse grumbling because his favorite type of equipment was not being installed.
“And there’s another thing,” he informed Doc. “The bases they’ve installed cannot be used for the type of turbines they’ve ordered. Changes will have to be made at a cost of 15-or-20 thousand dollars.”
“We’ll check up on the mistake,” Doc said grimly. “I want to question whoever is responsible. We’ll learn somehow who is behind all this sabotage.”
“I’ll make inquiries,” Long Tom declared.
Leaving the powerhouse, Doc strode along below the beetling cliff. Sun-baked muck of the dry river bed was underfoot. The stream had been hardly more than 50 feet wide here. The dark rock sides rose almost vertically.
Overhead, the wire hawsers of the cable cars draped like scattered, huge cobwebs.
A sharp thump of an explosion sounded.
Doc glanced around… then up. An appalling sight met his gaze.
The entire frowning chasm wall seemed to be sliding down upon him!
It was a rock slide of tremendous proportions! It extended for many yards in either direction. And enough stone was coming down to fill the entire stream bed!
Escape seemed a fantastic thought. Outrunning the avalanche was an impossibility. Scaling the opposite wall of the canyon was also beyond hope. It was rock worn glass-smooth by the rushing waters of ages.
Doc lost no time in aimless staring or speculation. He went into action as though he had practiced this very thing a thousand times.
His hand flicked out the silk cord and grapple. He flung it upward!
A single cable line of the many above was not anchored in the sliding wall. This hawser extended from a point near the dam diagonally down to the powerhouse which was just beyond the slide area.
The grapple seemed hardly to touch the aerial hawser before Doc was dangling from the silken cord, hauling himself up. Even then, he was none too quick. A boulder — leaping in advance of the rest — struck him. His bronze form swung like a penny on a string.
Roaring, cracking, and grinding with cataclysmic fury, the slide piled into the canyon bed. Rocks the size of houses bounced like marbles and smashed like snowballs. Dust vomited from the debris. It enveloped Doc’s rapidly climbing form.
The canyon quaked to the reverberations of rending stone. The dust spread and spread until it swathed even the dam scene itself in a choking fog. The slide was doing no damage to the dam, though.
Workmen — unable to tell the extent of the slide — became panic-stricken and fled their jobs. Yelling and cursing, they fought each other to be first up the truck roads.
Suddenly out of the dust haze enveloping the dam terminus of the powerhouse cableway, a mighty Bronze Man appeared.
His voice — crashing through the confusion with an uncanny Power! — arrested frightened men in their tracks. They listened to the bronze giant’s orders. Sheepish looks came to their faces. They returned.
Ambulances and fire wagons came caterwauling down the crooked road from Skullduggery. Women — whose men-folk were employed on the dam — trailed these in a hysterical horde.
An ambulance driver failed to allow enough for a turn. As a result, his vehicle rolled over twice without leaving the road. They hauled the driver out with a broken arm.
Amazingly enough, this man suffered the most drastic injury produced by the gigantic rock slide. There were numerous bruises, minor cuts, and a few black eyes and skinned knuckles — the latter among fellows who had fought to be first to imagined safety.
But not a man had perished in the slide!
Upon learning the latter fact, Doc took a curious viewpoint.
“It looks to me as if a lot of the workmen might have been expecting this and kept out of danger!” he informed Monk.
At this point, a burst of excited shouts drew Doc’s attention. He ran for the sound, rounded a spur of rock…
…and surprise halted him.
Johnny had his gaunt frame sprawled atop a prone man. The pair had evidently been fighting with Johnny the victor.
“What’s the trouble, Johnny?” Doc demanded.
“I caught this bird runnin’ from the place where the rock slide started!” gritted the bony geologist. “I think he caused it!”
Doc shifted to get a view of the prisoner’s features.
It was the red-whiskered member of the partner trio — Ossip Keller!
XVI — New Suspect
“That’s a blasted lie!” Ossip Keller bellowed. “I didn’t have a thing to do with the slide!”
Johnny arose, but retained a tight grip on Keller’s coat. “You were running away, though!”
“Sure I ran!” Keller said angrily. “Who wouldn’t? I thought it was an earthquake or somethin’!”
Twisting, he threw a fist at Johnny’s rail-thin midriff. The fist missed.