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Jabo checked the ship’s position again on the chart. He had just taken the conn, the officer of the deck on the six-to-midnight evening watch, still pleasantly full after a meal of spaghetti and meatballs. He could still smell the garlic bread, and hear the clatter below decks of the meal being cleaned up.

They were on track…barely. They’d run some drills that afternoon, what few drills they could run without slowing the ship much below the required twenty-two knot SOA: a radioactive spill in the engine room, an electrical grounding isolation exercise, a fire in the engine room. All lame, except for the fire. During that one they’d gone quickly to PD, practiced ventilating, and while they were up acquired the broadcast — Jabo still needed to review those messages. And, in a huge departure from the simulation while at PD, they shot what trash they could. A submarine disposed of trash by compacting it into metal cylinders ten inches in diameter and shooting them from the bottom of the boat in a device that functioned much like a torpedo tube. Getting rid of garbage was turning out to be one of the real limiting factors of their rapid advance across the Pacific. Like going to periscope depth, shooting trash required the ship to slow. But unlike acquiring the broadcast, shooting trash took more than twenty-three minutes, and the metal tubes were starting to pile up. The trash room was at capacity, and the overflow was now stacked in the torpedo room like cordwood. The smell was starting to become an issue, and the crew had taken to marking the ripest cylinders with yellow post-it notes so that, when the opportunity to shoot a few cylinders presented itself, the foulest would be sent to the bottom of the ocean first.

But Jabo’s next six hours represented the distillation of their priorities. There would be no going to PD, no shooting trash, and, most importantly, no slowing down. If they kept at twenty-three knots, by the end of his watch, they would have just made their way back to the red dot that marked their required position on the chart. By the end of the midwatch, they would have gotten ahead enough to allow another quick trip to PD, another broadcast, and maybe send a few more cylinders of trash to their watery grave.

He read the deck log entry from the last watch’s trip to PD and something caught his eye.

“Did you take this sounding?” he asked Flather.

“Yes sir.”

It was 1,850 fathoms. The chart, at the position of their fix, read 2,900 fathoms. “That’s a big difference.”

Flather shrugged. “Since it was more than ten percent off, we told the navigator and the captain. It’s in the standing orders. There’s still plenty of water under us.” And that was true. A fathom was six feet, so even at their current depth, with the current sounding, they had more than 1,000 fathoms, or six thousand feet, of water between them and the ocean bottom. Still, the discrepancy bugged him.

“Does that bother you?”

Flather shrugged again, this time in a way that said: I’ve got much bigger shit to worry about. “You know how these charts have been — they’re pretty sketchy. So I’m not entirely surprised that some of the soundings are a little off.”

“A little? It’s over a thousand fathoms off. A fucking mile.”

“Maybe it’s the fathometer,” said Flather. “It’s less accurate in very deep water.” Jabo could see that Flather was getting his back up, insulted by any implied inaccuracy on the chart or in the sounding.

“True enough,” said Jabo. “But let’s take another one. It’ll make me feel better.”

“Captain’s permission?”

“Don’t need it to use the secure fathometer at this speed.”

“Be aware that the secure fathometer is even less accurate, and this speed will degrade the accuracy even more,” said Flather. He was being pissy now.

“Noted.”

Flather turned to the console on his left, spun a few dials and flipped some switches, in a minute he was ready to go. He turned to Jabo for final confirmation.

“Go ahead.”

He pushed the button at the center of the console. A discrete, focused pulse of sound shot from the bottom of the boat to the ocean floor, then bounced back to the sensor on the hull. The fathometer measured exactly how long it took the sound to make its journey. It then corrected the speed of sound for the ocean’s temperature, one of the values Flather had entered, added in the depth of the boat, and in less than a second, displayed the depth of the ocean: 1,840 fathoms. Flather noted it in his log, then wrote the number, in his tiny, neat script, next to their estimated position on the broad, featureless chart of the Pacific that was supposed to tell them where on the planet they were. The consistency of the two readings, to Jabo, probably ruled out equipment malfunction. Which meant one of two equally disturbing possibilities: either their chart was inaccurate. Or they weren’t where they thought they were.