money they're not configged to detect or react from an underground penetration. Maybe we can 'stream' ANAD in…you know, a few mechs at a time--and not even be noticed. Config ourselves as dust motes, or gnats or something innocent like that. Once we're in, we form up into recon swarms and go about our business."
Winger shook his head. It was a truly crackpot idea. "It might just work."
Barnes was skeptical. "It's a tactical nightmare. How the hell do we communicate with ANAD--through solid rock? How does he navigate? We're talking big density problems here…pressure and temperature alone might even keep us from replicating. Nobody's ever tried to run a real assembler underground, not at any depth."
Gibby smiled his best little maverick smile. "Exactly. I know that. You know that. Probably Red Hammer knows that. Nobody will expect it. Nobody'll be looking for a nano breach from below ground."
Winger had gotten a warm, cuddly feeling about the idea. "It'll take some work. But I like it."
Delforza and Winger studied the imager screen on the interface control panel, both silently willing an image, something, to show up. The sims had predicted intermittent comm. The limestone cliff they had bored into was dense rock, structurally tight crystalline lattices of silicon and calcium and iron and half a dozen over things, with little room even for nanoscale bots to maneuver. Getting through the rock plates, let alone sending an acoustic or EM signal back, was dicey, and there were even bets around the Detachment on when comms would drop out altogether.
When it did, if it did, ANAD would be completely on his own, until he breached the floor seals of the Red Hammer compound.
"Getting something--" Gibby announced. He tweaked a dial, boosted the gain, and waved his hands around the imager, imploring a signal to come back--"--come on, baby…come on…give me a peek, just one little peek--"
Gradually, the imager settled down to a dark, staticky, grainy picture--of what? Winger squinted, leaned forward. The view slowly materialized--a dense, regular lattice of throbbing, quivering spheres.
"Crystalline structures," Gibby reported. "Looks like calcium. Maybe carbons—
Winger was mesmerized by the perfect geometry. "Oxygens too, Sergeant." He pointed to long rows of tiny darkened blobs, marching off into the distance like a fence. "A cubical lattice, just like the micrographs. A crystalline solid--"
"Limestone's mostly calcium anyway, with some oxygens and carbons mixed in. Interlocking crystals--it's beautiful."
"And damned hard to navigate. Like a jungle…this stuff's so dense, ANAD's speed is way down. Enable the voice link--"
Gibby tapped a few keys. "--to Hub…ANAD to Hub…ANAD is inside, pushing through some zone of crystalline cubes--" the voice was almost a whine, an impatient six-year old. "--very thick structure…getting jostled a bit…the atoms here are highly charged--probably covalent bonds…lots of electrons being swapped around--"
Winger opened the voice link. "ANAD, this is Hub…can you go any faster? We're behind the mission timeline."
There was a pause and the imager view jostled a bit. "Negative, Hub. ANAD at twenty percent propulsor…packing too tight here…high specific gravity…got many walls of lattice ahead…have to navigate each one…van der Waals forces are tricky--"
"How deep is he?" Winger asked.
Gibby checked the sounding return from the borehole. "Forty meters now…we should level off and turn northeast. The Red Hammer compound appears to be on a bearing of 072 degrees, judging from returns."
Winger studied the grid layout of the mountain, a 3-D projection of the limestone cliffs of Banikaiyan Mountain, with the presumed location of the lab sited in. ANAD's projected path was also laid in, a dotted line to the subsurface foundations of the structure…at least what Q2 had been able to determine from local and overhead surveillance.
"I agree. ANAD…steer right to heading 072 degrees. Maintain depth if you can. And increase propulsor power to forty percent."
Sounding showed ANAD had complied. The child's voice crackled over the speaker. "Steering right to 072…sedimentary layers getting smaller…almost no voids now…pressure rising, temperature too…ANAD safing outer effectors…can't squeeze between calciums otherwise…commands sent to all daughters--"
"Good idea," Winger muttered. He hadn't thought of that. ANAD had retracted its outer layer of effectors, stowing them for the journey. That should reduce interference with the ionic forces buffeting the tiny swarm. "He's learning, Gibby…"
"Learning fast, sir. Like a precocious child--"
"--propulsor power increased to forty percent…ANAD recommends safing effectors to stage one--density increases ahead--"
"He's right," Gibby saw. "Must be a concentration of heavier rock."
ANAD had asked permission to retract all effectors inside its body, leaving only its structural shell exposed.
"Permission granted--" Winger sent.
Gibby and Winger studied the soundings, following the progress of the swarm as it wound its way laboriously through denser rock, climbing slightly to negotiate a nearly impenetrable outcrop of black-streaked breccia. On the imager, the acoustic return revealed a solid wall of atoms, pressed together like layers of a pie. The image buffeted and quivered in a maelstrom of atomic forces and Brownian motion.
"Like swimming in molasses," said Deeno D'Nunzio. She was behind the IC panel, biting her fingernails.
"Molasses mixed with chunks of rubber," said Mighty Mite Barnes. She wasn't sure how well ANAD would perform filtering through the interstices of solid rock. Time would tell.
"Just squeezing through--" added Nguyen.
"Distance to the compound?" Winger asked.
Gibby did some quick checking. "About a hundred meters now, Skipper. ANAD's turned to an east by northeast tangent, skirting that dense outcrop. He's in some kind of clastic rock now…zone of sandstone and shale, mostly. Easier going."
Winger nodded. ANAD had made the maneuver on his own, determining from onboard sounding the density ahead, and made an adjustment.
"ANAD, this is Hub…report status--"
There was a slight delay, then the child's voice came back, muffled and scratchy, sounding tinny through the speaker. "ANAD at forty percent propulsor…density dropped off a third…ANAD cruising through brecciated shale…larger lattice, atom forces reduced--"
The traverse through the innards of Banikaiyan Mountain took another hour. Winger thought: this is nothing like the classroom studies we’ve been doing at nog school. He ordered the assembler to rise closer to the surface, and, after an uneasy delay, ANAD complied. Comm was getting difficult, as had been expected. Propulsor power was raised to fifty percent. Just shy of 2200 hours, ANAD reported his position.
"ANAD to Hub…ANAD detecting foundation materials ahead…distance 7 x 10 exp 12 micrometers…slowing to twenty percent…daughter swarm re-grouping for penetration--"
Delforza pumped his fist exultantly. “That’s it…right where Q2 said it would be. There is something there.”
Winger and Gibby had already seen the acoustic image darken again, indicating denser material ahead.
"ANAD…all stop…" Winger commanded. "Hold your position--"
"What's up, Skipper?" Gibby looked up, puzzled.
Winger pursed his lips. "Just thinking, that's all. ANAD needs to look for a seam in the foundation. And he'd better probe for any guards too. I don't expect a barrier of nano, but we'd better be sure. No sense waking everybody up if we don't have to."
Gibby was tuning the acoustic sounder, sampling reflected echoes from the subsurface structures a kilometer above the convoy of vans. "Mmmm…don't see any breaks in the thing…nothing like a seam, Lieutenant. If ANAD has to filter himself through the foundation--"
"--I know, I know. It'll take forever." Winger glared at Nguyen, then Deeno and Barnes, seeking answers. "We may have no choice though."
"He'll have to get real small to squeeze
through this," Gibby reported. "Look--" he pointed to a pattern of echoes on the screen. "Sounder says minimum lattice size is around seventy nanometers. That's about the size of ANAD's outer shell."
"Pulling in effectors may not be enough," Winger understood the dilemma. "I hate to do a quantum collapse now…it's risky and we might not get all the structure back…before we're detected. ANAD could traverse even that solid a material if he chopped off all effectors and folded in to his processor dot."
"But would he be able to find enough atoms of the right type, fast enough, on the other side?" asked Deeno. "It's dicey."
"And all the atom-grabbing would surely get somebody's attention," Nguyen added.
Winger had made up his mind. "We're going in like we are, even if it slows us down. ANAD'll just have to squeeze through. I'd better let him know. Hub to ANAD, report status--"
The voice was hollow, as if deep inside a tunnel, which in effect it was. "ANAD to Hub…ANAD group stable…stationkeeping seven minutes from foundation outer surface…ANAD embedded in chalk stratum now…effectors partially extended…feels much better--"
Johnny Winger's eyebrows went up at ANAD's last statement. Wonder what the little guy's feeling--"Hub to ANAD, config down to outer shell…fold in all effectors. Transit the foundation structure in this config."
The message went through the link. Comm was spotty through the mountain of solid rock. It took nearly a minute for ANAD to reply. The signal was weak.
"ANAD to