Shock Wave (Dirk Pitt 13)

"What is it?"

"Follow me a hundred meters up the shaft and I'll show you your missing piece."

Pitt trailed in the engineer's footsteps until they reached a side shaft, only this one held no shorin

g timbers. The volcanic rock that made up its rounded sides was almost as smooth as if it had been polished by some immense boring tool.

"A Thurston lava tube," Pitt said. "I've seen them on the big island of Hawaii."

"Certain lavas such as those basaltic in composition form thin flows called pahoehoe that run laterally, with smooth surfaces," clarified the engineer. "When the lava cools closer to the surface, the deeper, warmer surge continues until it flows into the open, leaving chambers, or tubes as we call them. It is these pockets of air that are driven to resonate by the pulsed ultrasound from the mining operation above."

"What if I remove the helmet?"

The engineer shrugged. "Go ahead, but you won't enjoy the results."

Pitt lifted the acoustic-foam helmet from his ears. After half a minute he became disoriented and reached out to the wall of the tube to keep from losing his balance. Next came a mushrooming sensation of nausea. The engineer reached over and replaced the helmet on Pitt's head. Then he circled an arm around Pitt's waist to hold him upright.

"Satisfied?" he asked.

Pitt took a long breath as the vertigo and nausea quickly passed. "I had to experience the agony. Now I have a mild idea of what those poor souls suffered before they died."

The engineer led him back to the elevator. "Not a pleasant ordeal. The deeper we excavate, the worse it becomes. The one time I walked in here without protecting my ears, my head ached for a week."

As the elevator rose from the lava tube, Pitt fully recovered except for a ringing in his ears. He knew it all now. He knew the source of the acoustic plague. He knew how it worked to destroy. He knew how to stop it -and was buoyed by the knowledge.

"I understand now. The air chambers in the lava resonate and radiate the high-intensity sound pulses down through rock and into the sea, producing an incredible burst of energy."

"There's your answer." The engineer removed his helmet and ran a hand through a head of thinning gray hair. "The resonance added to the sound intensity creates incredible energy, more than enough to kill."

"Why did you risk your job and maybe your life showing me this?"

The engineer's eyes burned, and he shoved his hands deep into the pockets of his jumpsuit. "I do not like working for people I cannot trust. Men like Arthur Dorsett create trouble and tragedy-if you two should ever meet, you can smell it on him. This whole operation stinks, as do all his other mining operations. These poor Chinese laborers are driven until they drop. They're fed well but paid nothing and forced to slave in the pit eighteen hours a day. Twenty have died in the past twelve months from accidents, because they were too exhausted to react and move out of the way of the equipment. Why the need to dig diamonds twenty-four hours a day when there is a worldwide surplus of the damned stones?

De Beers may head a repugnant monopoly, but you have to give them credit. They hold production down so prices remain high. No, Dorsett has a rotten scheme to harm the market. I'd give a year's pay to know what's going on in his diabolic mind. Someone like you, who understands the horror we're causing here, can now work to stop Dorsett before he kills another hundred innocent souls."

"What's stopping you from blowing the whistle?" asked Pitt.

"Easier said than done. Every one of the scientists and engineers who direct the digging signed ironclad contracts. No performance, no pay. Dorsett's attorneys would throw up a smoke screen so thick you couldn't cut it with a laser if we sued. Just as bad, if the Mounties learned of the carnage among the Chinese laborers, and the cover-up, Dorsett would claim ignorance and make damned certain we'd all stand trial for conspiracy. As it is, we're scheduled to leave the island in four weeks. Our orders are to shut down the mine the week before. Only then are we to be paid off and sent on our way."

"Why not get on a boat and leave now?"

"The thought crossed our minds until the chief superintendent tried exactly that," said the engineer slowly. "According to letters we received from his wife, he never arrived home and was never seen again."

"Dorsett runs a tight ship."

"As tight as any Central American drug operation."

"Why shut down the mine when it still produces?"

"I have no idea. Dorsett set the dates. He obviously has a plan he doesn't intend to share with the hired help."

"How does Dorsett know none of you will talk once you're on the mainland?"

"It's no secret that if one of us talks, we all go to jail."

"And the Chinese laborers?"

He stared at Pitt over the respirator clamped around the lower part of his face, his eyes expressionless. "I have a suspicion they'll be left inside the mine."