A few yards away, Dahlgren was driving his probe into the sand. Out of the corner of his eye, Dirk noticed him suddenly rise off the bottom. Something about the movement didn't seem right and Dirk looked over to see that his instincts were right. Dahlgren had let go of the probe and had his hands wrapped around his faceplate and air line, while his legs hung loose beneath him. He was being yanked off the bottom, Dirk realized, like a puppet on a string.
He had no time to react, for an instant later the airlift was ripped from his own hands, sailing off through the water in the direction of Dahlgren. Dirk looked up just in time to see his own air line pull taut in the water and then jerk him up off the seafloor.
"What the . . ." he started to mouth, but the words fell away as he tried to draw a breath of air. He inhaled a slight puff and then there was nothing. The compressor supplying the air lines had been cut off, too. Like Dahlgren, he found himself grabbing hold of the air line to control his movements and not rip the connection from his dive helmet. Beside him, the airlift swung wildly in the water like a pendulum out of control. The big plastic pipe came barreling at him, slamming into his leg before bouncing off in another direction. Out of air, yanked like a rag doll, and pummeled by the airlift, Dirk faced enough sensory obstacles to drive most people to panic. From there, it would be just a short step to drowning.
But Dirk didn't panic. He had spent the better part of his life scuba diving. Technical failures underwater were nothing new to him. He had sucked a tank of air dry on shallow-water dives many times. The key to surviving an emergency, underwater or elsewhere, he told himself, was to remain calm and think logically.
Air was the first necessity. His natural inclination was to kick to the surface, but that wasn't necessary. While working on surface-supplied air, the divers all carried a small emergency bottle of air. Slightly larger than a thermos, the thirteen-cubic-foot bailout bottle, called a "pony tank," provided about ten minutes of air. Dirk let go of the air line with one hand and reached under his left arm, where the bottle was attached to his buoyancy compensator. Twis
ting the valve on the top of the tank, he immediately drew in a breath of air through the regulator. After a couple of deep draws, he could feel his heart begin to slow its racing beat.
His thoughts ran to Dahlgren, who was on the shared line of surface air. Thirty feet ahead, he saw a purge of exhaust bubbles rise from Dahlgren's helmet and knew that he was breathing off his emergency air as well. The dangling airlift had ventured over toward Dahlgren and was gyrating in the water close behind him. The airlift pipe was being dragged by its flexible outlet hose secured to the barge, which created an elastic springing action like a rubber band. The hose would stretch under the drag of the water-filled tube, then snap back, whipping the tube forcefully through the water. Dirk saw that the tube was pulled taut in a precarious position behind Dahlgren and he waved to get his friend's attention. The Texan was busy pulling himself up the air line and didn't see the airlift or Dirk's warning. A second later, the outstretched tube burst forward, launching straight toward Dahlgren. To Dirk's horror, the tube shot up like an arrow and struck the back of Dahlgren's head just beneath his dive helmet. As the airlift fluttered off, Dahlgren's body went limp.
Dirk cursed to himself as he felt his heart race faster again. He noticed that the seafloor had dropped away beneath them and that they were being pulled more forcefully through the water. On the surface, an offshore breeze had joined forces with the island currents to push the stubby barge along at over four knots. Under the waves, Dirk wondered why in blazes the barge was drifting and where Summer was. Then he turned toward Dahlgren. There was no thought of surfacing yet. He had to reach Dahlgren and make sure he was still breathing.
With a frantic determination, Dirk began reeling himself up the air line to close in on Dahlgren. His tired arms ached in pain with each pull, made harder by the thirty-five-pound weight belt strapped around his midsection. He didn't dare jettison the belt yet, as he needed to stay at the same submerged depth as his friend.
Pulling himself up like an underwater mountaineer, he clawed his way to within ten feet of Dahlgren when his old nemesis reappeared. The dancing airlift came rushing toward him, swinging past just out of arm's reach. The big tube swung toward Dahlgren, flexed a moment, then reversed direction and bounded back. This time, Dirk stuck out an arm and caught hold of the tube as it swung by. The heavy mass of the water-filled tube nearly jerked him out of his fins as he straddled his legs around it and bounced through the water. Riding it like a bucking bronco, he carefully shimmied up to the top of the tube, where it was clasped to the thick rubber hose. Pulling out a small dive knife that was strapped to his leg, Dirk lunged at the hose with the blade and began sawing through it. The tube whipped violently beneath him as he muscled the knife through to sever the hose. The heavy plastic tube snapped away with the last cut and sank to the depths as Dirk slid off and gave it a farewell kick.
Free of the mad battering ram, Dirk turned his attention back to Dahlgren. Dirk's fight to rid himself of the airlift had caused him to lose his place on the air line and he found himself trailing Dahlgren by thirty feet again. His friend looked like a wet mop, towed through the water by the line from his neck. With his tired arms stinging, Dirk pulled himself up the line again, fighting foot by foot until he was even with Dahlgren. He coiled his own air line around his waist in a bowline knot, then kicked and swam his way over to his friend. Reaching over and grabbing Dahlgren's BC, Dirk pulled himself up and peered into his face mask.
Dahlgren was unconscious with his eyes closed. He was breathing lightly, though, as evidenced by a small stream of exhaust bubbles that floated out of his regulator every few seconds. Grabbing Dahlgren with one hand, Dirk reached down and unbuckled his own weight belt, then reached up to his buoyancy compensator and hit the button on the inflation hose. What little air was left in his emergency pony bottle surged into his vest, filling it half full before running out of compressed air. It was more than enough to propel them to the surface, with Dirk kicking his legs hard to accelerate the ascent.
No sooner did they break the surface then they were dragged forward, yanked under the water like a fallen water-skier who forgets to let go of the rope. A second later, they would resurface for a moment, then get pulled under again. As they bounded up and down, Dirk reached down and ditched Dahlgren's weight belt, then managed to twist off his own dive helmet. Grabbing gulps of air when they popped to the surface, he grasped the manual inflation tube to Dahlgren's BC. While pushed under the surface, he opened the thumb valve and exhaled into it. In a few cycles, he had Dahlgren's vest fully inflated, which helped reduce the duration of their immersions.
Fearful that his friend's head or neck might get injured by the tug of the air line, Dirk cinched up a few inches of the line and ran it through a D ring on Dahlgren's BC, then tied it in a knot. As long as the line didn't snap, he would safely be towed by his vest.
With his buddy mostly afloat, Dirk let go of him to grab his own air line again. He had to get aboard the barge now and began pulling himself hand over hand toward the moving platform. There was more than forty feet of line ahead of him, and he was already heavily fatigued from his time in the water. With his strength diminished, his progress slowed to just inches at a time. He repeatedly had to will himself to shake off the pain and a creeping urge to just let go. Instead, he reluctantly placed one hand ahead of the other and pulled, repeating the process without stopping.
For the first time, he looked up at the barge, hoping to see Summer standing at the rail. But there was no sign of her or anyone else on the open deck. Dirk knew his sister would never willfully abandon him. Something had happened when the black ship came alongside and Dirk was afraid of the prospects. A renewed sense of urgency mixed with anger surged through his body, and he hauled himself up the last few feet of line in a possessed fury.
Finally reaching the side of the barge, he yanked himself up and through the railing and collapsed on the deck. He afforded himself just a few seconds of rest, then ripped off his dive gear and scanned the deck for Summer, shouting her name. Met with a silent response, he stood up and grabbed Dahlgren's air line and began reeling him toward the barge. The Texan disappeared under the water for several seconds before reappearing, as larger ocean-borne waves rolled over him. He had regained consciousness and slowly kicked his legs and arms in a mostly futile attempt at propulsion. With his arms fatigued nearly to the breaking point, Dirk pulled him alongside the barge, then tied off the air line on the rail. Reaching into the water, he grabbed Dahlgren by the collar and hoisted him aboard.
Dahlgren rolled onto the deck, then teetered to a sitting position. He clumsily pulled off his dive helmet and gazed at Dirk with blurry eyes. Rubbing the back of his neck with one hand, he winced as his fingers rolled over a baseball-sized lump.
"What in blazes happened down there?" he asked in a slurred voice.
"Before or after the airlift used your skull for batting practice?" Dirk replied.
"So that was the sucker that hit me. I remember getting yanked off the bottom, then my air went dry. I hit my pony tank and was preparing to ascend when the lights went out."
"Lucky thing you cranked on your emergency air. It took me a few minutes to ditch the airlift and get you to the surface amid the tow ride."
"Thanks for not throwing me back," Dahlgren smiled, his senses slowly returning. "So where's Summer? And why are we twenty miles from shore?" he asked, noting the rugged coast of Hawaii receding in the distance.
"I don't know," Dirk said solemnly.
As Dahlgren rested, Dirk searched the shack and examined the rest of the barge for signs of Summer's disappearance. When he returned, Dahlgren could tell by the look on his face that the news was not good.
"Radio is gone. Zodiac is gone. Generator is missing. And all of our mooring lines were cut at deck level."
"And we're drifting to China. Pirates in Hawaii?"
"Or treasure hunters thinking we had a gold ship." Dirk stared back toward the island. He could no longer see the cove but knew the black ship was still there.
"The ship we heard roll in?" Dahlgren asked, his vision too fuzzy to see for himself.
"Yes."