Quickly, almost fearfully, picking through the rich litter of wreckage, Martha discovered that the mother tank they used to replenish their airpacks had ruptured.

Terrific. That left her own pack, which was one-third empty, two fully charged backup packs, and Burton's, also one-third empty. It was a ghoulish thing to strip Burton's suit of her airpack, but it had to be done. Sorry, Julie. That gave her enough oxygen to last, let's see, almost forty hours.

Then she took a curved section of what had been the moonrover's hull and a coil of nylon rope, and with two pieces of scrap for makeshift hammer and punch, fashioned a sledge for Burton's body.

She'd be damned if she was going to leave it behind.

Click.

"This is. Better."

"Says you."

Ahead of her stretched the hard, cold sulfur plain. Smooth as glass. Brittle as frozen toffee. Cold as hell. She called up a visor-map and checked her progress.

Only forty-five miles of mixed terrain to cross and she'd reach the lander. Then she'd be home free. No sweat, she thought. Io was in tidal lock with Jupiter. So the Father of Planets would stay glued to one fixed spot in the sky. That was as good as a navigation beacon. Just keep Jupiter to your right shoulder, and Daedalus to your left. You'll come out fine.

"Sulfur is. Triboelectric."

"Don't hold it in. What are you really trying to say?"

"And now I see. With eye serene. The very. Pulse. Of the machine." A pause.

"Wordsworth."

Which, except for the halting delivery, was so much like Burton, with her classical education and love of classical poets like Spenser and Ginsberg and Plath, that for a second Martha was taken aback. Burton was a terrible poetry bore, but her enthusiasm had been genuine, and now Martha was sorry for every time she'd met those quotations with rolled eyes or a flip remark. But there'd be time enough for grieving later. Right now she had to concentrate on the task at hand.