The armies fanned deeper, acquiring a vast and complex sub-geography beneath the iron mines of West Cumberland in South Wales and the Holloch in Switzerland and Epos Chasm in Greece and the Picos Mountains in Basque country and the coal pits in Kentucky and the cenotes of Yucatàn and the diamond mines in South Africa and dozens of other places. The northern hemisphere was exceptionally rich in limestone, which fused at lower levels into warm marble and beerstone and eventually, much deeper, into basalt. This bedrock was so heavy it underlay the entire surface world. Because man had rarely burrowed into it – a few exploratory probes for petroleum and the long-abandoned Moho project – geologists had always assumed that basalt
was a solid compressed mass. What man now found was a planetary labyrinth. Geological capillaries stretched for thousands of miles. It was rumored they might even reach out beneath the oceans.
Nine months passed. Every day the armies pushed their collective knowledge a little further, a little deeper. The Army Corps of Engineers and the Seabees saw their budgets soar. They were tasked to reinforce tunnels, devise new transport systems, drill shafts, build elevators, bore channels, and erect whole camps underground. They even paved parking lots – three thousand feet beneath the surface. Roadways were constructed through the mouths of caves. Tanks and Humvees and deuce-and-a-half trucks pouring ordnance, troops, and supplies into the inner earth.
By the hundreds, international patrols descended into the earth's recesses for more than half a year. Boot camps shifted their theater training. Jarheads sat through films from the United Mine Workers about basic techniques for shoring walls and maintaining a carbide lamp. Drill instructors began taking recruits to the rifle ranges at midnight for point-and-fire practice and blindfolded rappels. Physician assistants and medics learned about Weill's disease and histoplasmosis, fungal infections of the lungs contracted from bat guano, and Mulu foot, a tropical cave disease. None were told what practical use any of this had. Then one day they would find themselves shipped into the womb.
Every week the mass of 3-D, four-color worm lines expanded laterally and vertically beneath their maps of Europe and Asia and the United States. Junior officers took to comparing the adventure to Dungeons and Dragons without, exactly, the dragons or dungeons. Wrinkled noncoms couldn't believe their luck: Vietnam without the Vietnamese. The enemy was turning out to be a figment of one very disfigured major's imagination. No one but Branch could claim to have seen demons with fish-white skin.
Not that there weren't 'enemies.' The signs of habitation were intriguing, sometimes gruesome. At those depths, tracks suggested a surprising spectrum of species, everything from centipedes and fish to a human-sized biped. One leathery wing fragment stirred images of subterannean flight, temporarily reviving Saint Jerome's visions of batlike dark angels.
In the absence of an actual specimen, scientists had named the enemy Homo hadalis, though they were the first to admit they didn't know if it was even hominid. The secular term became hadal, rhyming with cradle. Middens indicated that these ape creatures were communal, if seminomadic. A picture of harsh, grinding, sunless subsistence emerged. It made the brute life of human peasantry look charming by comparison.
But whoever lived down here – and the evidence of primitive occupation at the deeper levels was undeniable – had been scared off. They encountered no resistance. No contact. No live sightings. Just lots of caveman souvenirs: knapped flint points, carved animal bones, cave paintings, and piles of trinkets stolen from the surface: broken pencils, empty Coke cans and beer bottles, dead spark plugs, coins, lightbulbs. Their cowardice was officially excused as an aversion to light. Troops couldn't wait to engage them.
The military occupation went deeper and wider in breathless secrecy. Intelligence agencies triumphed in embargoing soldiers' mail home, confining units to base, and derailing the media.