My warning was unnecessary. No one was feeling chatty. We'd just committed a felony.
Emerging, we found ourselves in a small tiled lobby. Directly opposite was the building's main entrance. In the rear left corner, a narrow staircase rose to a second floor. Gray light arrowed through dusty window blinds, throwing diagonal slashes across pale green walls, plastic trees, and a row of connected metal seats. The motif was corporate drab, as inviting as a lost baggage claim office.
Hi pointed to open double doors to our right. We scuttled through them, down a short hallway, through another set of doors, and into Lab Six.
The room had no windows, so we risked the lights. Ceiling fluorescents revealed a chamber the size of a large classroom. In the center were six workstations floor-bolted in two rows. Each station overflowed with equipment.
A stainless steel counter jutted from three walls of the room. Above it hung glass-fronted cabinets filled with beakers and other scientific apparatuses. Microscopes. Circular lenses. Gadgets whose functions were a mystery to me.
A Plexiglas enclosure occupied the right quarter of the room. Housing the more expensive technology, that section was locked and alarmed. Luckily, we needed nothing from there.
"Okay, hit it." Shelton nudged Hi into action. "Find the sonicator."
Moving to the third workstation in the second row, Hi removed a plastic cover from a small machine. "My precious," he rasped in his best Gollum impression.
The contraption consisted of a small white sink backed by an LCD control panel. About the size of a microwave, it resembled a tiny top-loading washer with the cover removed.
"Sweet, eh?"
Hi's father, Linus Stolowitski, was the mechanical engineer in charge of all LIRI scientific equipment. A technophile, he'd transmitted his love of gadgets to Hi.
"Sonicator is actually shorthand for ultrasonic cleaner." Hi spoke in his very best church voice. Temple voice?
"What's it do?" Shelton asked.
"The device uses ultrasound to clean objects." Hi worked as he talked, filling the basin with fluid. "We'll clamp the specimen an inch underwater."
Shelton's nose curled. "Whoa. That stuff smells like mega-strength Windex."
"It's cleaning solution," Hi said. "I've set the machine's frequency for the type of object we're trying to clean, and for the type of substance we're trying to remove. In this case, metal and dirt."
Shelton looked lost. Ben looked bored.
"It's like a sonar washing machine," Hi explained. "The ultrasound enhances the cleaning solution's effect." He paused. "Do you guys know what 'cavitation bubbles' are?"
Nope.
"A sonicator has a transducer that produces ultrasonic waves in the fluid. That creates compression waves, which rip the fluid apart, leaving behind millions of microscopic 'voids' or 'vacuum bubbles.' That's called cavitation."
Okay. That was pretty cool.
"In our case, the cavitation bubbles will penetrate microscopic holes, cracks, and recesses in the dog tag. Then they'll collapse, creating energy pockets. The reaction should remove even deeply embedded particles."
"So when the mini-bubbles burst they blast away the gunk?" I summarized.
"Exacto." Hi was enjoying his lecture. "Like tiny scrubbing dynamite."
"Why's the thing here?" Shelton asked.
"Sonicators are used for cleaning glasses, jewelry, and metal stuff like coins and watches. Even cell phone parts. Dentists, doctors, and hospitals use the gizmos to clean instruments."
"And scientists." Shelton had his answer.
Satisfied with the settings, Hi extended a hand in my direction. "The ring, Frodo?"
I pulled a plastic baggie from my pocket and removed the dog tag. Seeing the cement-like crust, my confidence faltered.
"This thing better work," Shelton said. "We're risking our butts to use it."
"How long?" Ben asked, already restless.
"Fifteen minutes. Get out of my hair and it might go faster."
Ben checked his watch, then wandered off the way we'd come in.
Shelton settled into a chair to wait.
Knowing we'd need something to view the tag once it was cleaned, I scanned the lab for optical equipment.
One counter had a Luxo lamp clamped to its top. The movable-arm magnifier lens was surrounded by a circular fluorescent bulb. Perfect. In a drawer I found several hand lenses and a penlight and placed them beside it. Viewing station complete.
"Five more minutes," Hi chirped. His love of experiments had overridden his fear of capture.
"I'll get Ben," I volunteered.
I checked the hallway and lobby, but found both empty.
"Ben?" I hissed, as loudly as I dared.
No answer.
I considered yelling up the stairs, decided against it. Not wanting to stumble around in the dark, I returned to Lab Six.
A series of beeps was announcing the end of the cleaning cycle.
"All rriiighty then!" Hi removed the tag and ran it under cold water. I watched over his shoulder.