Mahnmut shook his red and black head. “The pulse units are for propellant. To get us to Earth.”

Hockenberry raised his palms to show his lack of understanding.

“These huge piston things are… well… pistons,” said Orphu. “On the way to Earth, we’ll be kicking a bomb out through a hole in the center of the pusher-plate beneath us about once every second for the first few hours—then once an hour for much of the rest of the flight.”

“For every pulse cycle,” adds Mahnmut, “we eject a charge—you’d just see a puff of steam out in space—we spray oil on the pusher-plate out there to act as an anti-ablative for the plate and the ejection tube muzzle, then the bomb explodes, and there’d be a flash of plasma that slams against the pusher-plate.”

“Wouldn’t that destroy the plate?” said Hockenberry. “And the ship?”

“Not at all,” said Mahnmut. “Your scientists worked all this out in the 1950s. The plasma event slams the pusher-plate forward and drives these huge reciprocating pistons back and forth. Even after just a few hundred explosions behind our butt, the ship will begin to pick up some real speed.”

“These gauges?” said Hockenberry, putting his hand on one that looked like a steam pressure gauge.

“That’s a steam pressure gauge,” said Orphu of Io. “The one next to it is an oil pressure gauge. The one above you there is a voltage regulator. You were right, Dr. Hockenberry… this room would be more quickly understood and manned by an engineer from the Titanic in 1912 than by a NASA engineer from your era.”

“How powerful are the bombs?”

Shall we tell him? sent Mahnmut.

Of course, tightbeamed Orphu. It’s a little late to start lying to our guest now.

“Each propellant charge packs a little more than forty-five kilotons,” said Mahnmut.

“Forty-five kilotons each—twenty-four thousand-some bombs,” muttered Hockenberry. “Are they going to leave a trail of radioactivity between Mars and Earth?”

“They’re fairly clean bombs,” said Orphu. “As fission bombs go.”

“How big are they?” asked Hockenberry. He realized that the engine room must be hotter than the rest of the ship. There was sweat beaded on his chin, upper lip, and brow.

“Come up a level,” said Mahnmut, leading the way to a spiral stairway broad enough for Orphu to repellor up the wide steps with them. “We’ll show you.”

Hockenberry guessed the room to be about a hundred and fifty feet in diameter and half that tall. It was almost completely filled with racks and conveyor belts and metal levels and ratcheting chains and chutes. Mahnmut pushed an oversized red button and the conveyor belts and chains and sorting devices began whirring and moving, shunting along hundreds or thousands of small silver containers that looked to Hockenberry like nothing so much as unlabeled Coke cans.

“It looks like the inside of a Coca-Cola dispenser,” said Hockenberry, trying to lighten the sense of doom he was feeling with a bad joke.

“It is from the Coca-Cola company, circa 1959,” rumbled Orphu of Io. “The designs and schematics were from one of their bottling plants in Atlanta, Georgia.”

“You put in a quarter and it dispenses a Coke,” managed Hockenberry. “Only instead of a Coke, it’s a forty-five-kiloton bomb set to explode right behind the tail of the ship. Thousands of them.”

“Correct,” said Mahnmut.

“Not quite,” said Orphu of Io. “Remember, this is a 1959 design. You only have to put in a dime.”

The Ionian rumbled until the silver cans in the moving conveyor belt rattled in their metal rings.

Back in the hornet, just Mahnmut and him, climbing toward the widening disk of Mars, Hockenberry said, “I forgot to ask… does it have a name? The ship?”

“Yes,” said Mahnmut. “Some of us thought it needed a name. We were first considering Orion …”

“Why Orion?” said Hockenberry. He was watching the rear window where Phobos and Stickney Crater and the huge ship were fast disappearing.

“That was the name your mid-Twentieth Century scientists gave the ship and the bomb-propellant project,” said the little moravec. “But in the end, the prime integrators in charge of the Earth voyage accepted the name that Orphu and I finally suggested.”

“What’s that?” Hockenberry settled deeper into his forcefield chair as they began to roar and sizzle into Mars’ atmosphere.

“Queen Mab,” said Mahnmut.

“From Romeo and Juliet,” said Hockenberry. “That must have been your suggestion. You’re the Shakespeare fan.”

“Oddly enough, it was Orphu’s,” said Mahnmut. They were in atmosphere now and flying over the Tharsis volcanoes toward Olympus Mons and the Brane Hole to Ilium.

“How does it apply to your ship?”

Mahnmut shook his head. “Orphu never answered that question, but he did cite some of the play to Asteague/Che and the others.”

“Which part?”

… and so on and so forth,” said Mahnmut.

“And so on and so forth,” repeated Dr. Thomas Hockenberry, Ph.D. Olympus Mons, the gods’ Olympos, was filling all the forward windows. According to Mahmut, the volcano was a mere 69,841 feet above Martian sea level—more than 15,000 feet shorter than people in Hock-enberry’s day had thought, but tall enough.’Twil serve, thought Hockenberry.

And up there, on the summit—the grassy summit—under the glowing aegis now catching the late-morning light—there were living creatures. And not just living creatures, but gods. The gods. Warring, breathing, fighting, scheming, mating creatures, not so unlike the humans Hockenberry had known in his previous life.

At that moment, all the clouds of depression that had been gathering around Hockenberry for months blew away—like the streamers of white cloud he could see blowing south from Olympos itself as the afternoon winds picked up from the northern ocean called the Tethys Sea—and at that moment, Thomas C. Hockenberry, Ph.D. in classics, was simply and purely and totally happy to be alive. Whether he chose to go on this Earth expedition or not, he realized, he would change places right then with no one in any other time or at any other place.

Mahnmut banked the hornet to the east of Mons Olympus and headed for the Brane Hole and Ilium.