"The Glass Sea," I said. Every Martian was given a Glass Sea fossil at some point in their childhood.
Charles steered us around a basalt-capped turban of limestone. Basalt fragments from an ancient meteor impact lay scattered over the area. I tried to imagine the meteor striking the middle of the shallow ocean, spraying debris for hundreds of kilometers and throwing up a cloud of muddy rain and steam . . . Devastation for an already fragile ecology. "Makes me twitchy," I said.
"What does?"
"Time. Age. Makes our lives look so trivial."
"We are trivial," Charles said.
I set my face firmly and shook my head. "I don't think so. Empty time isn't very . . . " I searched for the right word. What came to mind were warm, alive, interesting, but these words all seemed to reveal my feminine perspective, and Charles's knee-jerk response had been decidedly masculine and above-it-all intellectual. "Active. No observers," I concluded lamely.
"Given that, we're still here for just an instant, and the changes we make on the landscape will be wiped out in a few thousand years."
"I disagree," I continued. "I think we're going to make a real mark on things. We observe, we plan ahead, we're organized — "
"Some of us are," Charles said, laughing.
"No, I mean it. We can make a big difference. All the flora and fauna on Mars were wiped out because they . . . " I still couldn't clearly express what I wanted to say.
"They weren't organized," Charles offered. "Right."
"Wait until you see," Charles said.
I shivered. "I don't want to be convinced of my triviality."
"Let the land speak," Charles said.
I had never been very comfortable with large ideas — astrophysics, areol-ogy, all seemed cavernous and dismal compared to the bright briefness of human history. In my studies I focused on the intricacies of politics and culture, human interaction; Charles I think preferred the wide-open territories of nature without humanity.
"We interpret what we see to suit our own mindset," I said pompously.
For a moment, his expression — downturned corners of his mouth, narrowed eyes, a little shake of his head — made me regret those words. If I was playing him like a fish on a line, I might have just snapped the line, and I suddenly felt terribly insecure. The touch of my glove on his thick sleeve did not seem adequate. "I still want to go and see," I said.
Charles let go of the guide stick. The tractor smoothed to a stop and jerked. He half-turned in his seat. "Do I irritate you?" he asked.
"No, why?"
"I feel like you're testing me. Asking me key questions to see if I'm suitable."
I bit my lip and looked into my lap, trying for some contrition. "I'm nervous," I said.
"Well, so am I. Maybe we should just let up a bit and relax."
"I was just expressing an opinion," I said, my own temper flaring. "I apologize for being clumsy. I haven't been here before, I don't know you very well, I don't know what — "
Charles held up his hands. "Let's forget all of it. I mean, let's forget everything that stands between us, and just try to be two friends out on a trip. I'll relax if you will. Okay?"
I came dangerously close to tears at the anger in his tone. I looked out the window but did not see the ancient carved grotesques outside.
"Okay?" he asked.
"I don't know how to be different," I said. "I'm not good at masks."
"I'm not either, and I don't like trying. If I'm not the right person for you, let's put it all aside and just enjoy the trip."
"I don't know what's making you so angry."
"I don't know, either. I'm sorry."
He pulled the stick forward and we drove in silence for several minutes. "Sometimes I dream about this," he said. "I dream I'm some sort of native Martian, able to stand naked in the Up and feel everything. Able to travel back in time to when Mars was alive."
"Coin-eyed, slender, nut-brown or bronze. 'Dark they were, and golden-eyed.'"
"Exactly," Charles said. "We live on three Marses, don't we? The Mars they made up back on Earth centuries ago. LitVid Mars. And this."
The tension seemed to have cleared. My mood shifted wildly. I felt like crying again, but this time with relief. "You're very tolerant," I said.
"We're both difficult," Charles said. He leaned to one side and bumped helmets with me. Our lips could get no closer, so we settled for that.
"Show me your Mars," I told him.
The melt river canyon stretched for thirty kilometers, carving a wavering line across the flats. A service path had been carved into the cliffs on both sides, cheaper than a bridge, marring the natural beauty but making the canyon bottom accessible to tractors.
"The areology here is really obvious," Charles said. "First comes the Glass Sea, then Tharsis One with deep ocean deposits, building up over a billion years, limestone . . . Then ice sheets and eskers . . . Then the really big winds at the end of the last glaciation."
We rolled down the gentle packed tumble slope into the canyon. The walls on each side were layered with iron-rich hematite sands and darker strata of clumped till. "Wind and ice," I said.
"You got it. Flopsand and jetsand, smear, cling and grind . . . There's a pretty thick layer of northern chrome clay." Charles pointed to a gray-green band on our right, at least a meter deep. He swerved the tractor around a recent boulder fall, squeezed through a space barely large enough to admit us, and we came out twenty meters below the flats. Our treads pushed aside flopsand to reveal paler grades of grind and heavy till.
"We have as many words for sand and dust as the Inuit have for snow," Charles said.
"Used to be a school quiz," I said. "'remember all the grades of dust and sand and name them in alphabetical order.' I only remember twenty."
"Here we are," Charles said, letting the stick go. The tractor slowed and stopped with a soft whine. Outside the cabin, silence. The high wind of the night before had settled and the air was still. A dust-free sky stretched wall-to-wall pitch-black. We might have been on Earth's moon but for the color of the canyon and the rippled red and yellow bed of the ancient melt river.
Charles enjoyed the silence. His face had a look of relaxed concentration. "There's a rock kit in the boot. We'll dig for an hour and return to the tractor." He hesitated, thinking something over. 'Then we'll head home. I mean, back to the station."
We checked our gear thoroughly, topped up our air supply from the tractor's tanks, pumped the cabin pressure into storage, and stepped through the curtain lock with a small puff of ice crystals. The crystals fell like stones to the canyon floor.
"I remember this," Charles said over the suit radio. "It hasn't changed. The sand patterns are different, of course, and there have been a few slumps . . . but it looks real familiar. I had a favorite fossil bed about a hundred meters from here. My father showed it to me."
Charles portioned out my share of tools to carry, took my gloved hand, and we walked away from the tractor. I saw two deposition layers clearly outlined in a stretch of canyon wall that had not slumped: a meter of brown and gray atop several meters of pale yellow limestone, and below that, half a meter of grays and blacks.
We walked across shaved flats now, covered with sand; the oldest limestones, and beneath, the Glass Sea bottom. I drew in my breath sharply, a kind of hiccup, startled at how this realization affected me. Old Mars, back when it had been a living planet . . . Alive for a mere billion and a half years.
Where life arose first was still at issue; Martians claimed primacy, and Terrestrials disputed them. But Earth had been a more violent and energetic world, closer to the sun, bombarded by more destructive radiation . . . Mars, farther away from its youthful star, cooling more rapidly, had condensed its vapor clouds into seas a quarter of a billion years earlier.
I believed — like most loyal Martians — that this was where life had first appeared in the Solar System. My feet pressed thin flopsand five or six centimeters above the graveyard of those early li
ving things.
"Here," Charles said, taking us into the inky shadow of a precarious overhang. I looked up, worried by the prominence. Charles saw my expression as he stooped and brought out his pick hammer. "It's okay," he said. "It was here when I was a kid. Can you shine a light?"
We worked by torch. Charles pried up a slab of dense crumbling limestone. I helped lift the slab away, twenty or thirty kilos of rock, piling it to one side. Charles handed me the pick.
"Your turn," he said. "Under this layer. About a centimeter down."
I swung the pick gently, then harder, until the layer cracked and I was able to finger and brush away the fragments, clearing a space a couple of hands wide. Charles held the torch.
I peered back through two billion Martian years and saw the jewel box of the past, pressed thin as a coat of paint, opalescent against the dark strata of those siliceous oceans.
Round, cubic, pyramidal, elongated, every shape imaginable, surrounded by glorious feathery filters, long stalks terminating in slender, gnarled roots: the ancient Glass Sea creatures appeared like illustrations in an old book, glittering rainbows of diffraction as the torch moved. I specked them waving in the soup-thick seas, sieving and eating their smaller cousins.
"Sometimes they'd lift from their stalks and float free," Charles said. I knew that, but I didn't mind him telling me. "The biggest colonies were maybe a klick wide, clustered floats, raising purple fans out of the water to soak up sunlight ..."
I reached down with my gloved hand to touch them. They had been glued firmly against their deathbed; they were tough, even across the eons.
"They're gorgeous," I said.
"The first examples of a Foster co-genotypic bauplan," Charles said. "These are pretty common specimens. No speciation, all working from one genetic blueprint, making a few hundred different forms. All one creature, really. Some folks think Mars never had more than nine or ten species living at a time. Couldn't call them species, actually — co-genotypic phyla is more like it. No surprise this kind of biology would give rise to the mother cysts."
He took a deep breath and stood. "I'm going to make a pretty important decision here. I'm trusting you."
I looked up from the Glass Sea, puzzled. "What?"
"I'd like to show you something, if you're interested. A short walk, another couple of hundred meters. A billion and a half years up. Earth years. First and last."
"Sounds mysterious," I said. "You hiding a mother deposit here?"
He shook his head. "It's on a secure registry, and we license it to scholars only. Father took me there. Made me swear to keep it secret."
"Maybe we should skip it," I said, afraid of leading Charles into violating family confidences.
"It's okay," he said. "Father would have approved."
"Would have?"
"He died on the Jefferson."
"Oh." The interplanetary passenger ship Jefferson had suffered engine failure boosting from around the Moon five Martian years before. Seventy people had died.
Charles had made a judgment on behalf of his dead father. I could not refuse. I stood and hefted my bag of tools.
The canyon snaked south for almost a hundred meters before veering west. At the bend, we took a rest and Charles chipped idly at a sheet of hard clay. "We've got about an hour more," he said. "We need fifteen minutes to get to where we're going, and that means we can only spend about ten minutes there."
"Should be enough," I said, and immediately felt like kicking myself.
"I could spend a year there and it wouldn't be enough," Charles said.
We climbed a gentle slope forty or fifty meters and abruptly came upon a deep fissure. The fissure cut across the canyon diagonally, its edges windworn smooth with age.
"The whole flatland is fragile," Charles said. "Quake, meteor strike . . . Something shook it, and it cracked. This is about six hundred million years old."
"It's magnificent."
He lifted his glove and pointed to a narrow path from the canyon floor, across the near wall of the fissure. "It's stable," he said. "Just don't slip on the gravel."
I hesitated before following Charles. The ledge was irregular, uneven, no wider than half a meter. I pictured a slip, a fall, a rip or prick in my suit.
Charles looked at me over his shoulder, already well down the ledge. "Come on," he said. "It's not dangerous if you're careful."
"I'm not a rock climber," I said. "I'm a rabbit, remember?"
"This is easy. It's worth it, believe me."
I chose each step with nervous deliberation, mumbling to myself below the microphone pickup. We descended into the crevice. Suddenly, I couldn't see Charles. I couldn't hear him on radio, either. We were out of line of sight and he was not getting through to a satcom transponder. I called his name several times, clinging to the wall, each moment closer to panic and fury.
I was looking back over my left shoulder, creeping to my right, when my hand fell into emptiness. I stopped with a low moan, trying to keep my balance on the ledge, waving for a grip, and felt a gloved hand take hold of my arm.
I turned and saw Charles right beside me. "Sorry," he said. "I forgot we wouldn't be able to talk through the rock. You're fine. Just step in ..."
We stood in the entrance to a cave. I hugged Charles tightly, saying nothing until my hammering heart had settled.
The cavern stabbed deep into the fissure wall, ending in black obscurity. Its ceiling rose five or six meters above our heads. The fissure's opposite wall reflected enough afternoon sunlight into the cavern that we could see each other clearly. Charles lifted the torch and handed it to me. "It's the last gasp," he said.
"What?" I still hadn't recovered my wits.
"We've gone from alpha to omega."
I scowled at him for his deliberate mystery, but he wasn't looking at me.
Gradually, I realized the cavern was not areological. The glass-smooth walls reflected the backwash of light with an oily green sheen. Gossamer, web-like filaments hard as rock stretched across the interior and flashed in my wavering torch beam. Shards of filament littered the floor like lost fairy knives. I stood in the silence, absorbing the obvious: the tunnel had once been part of something alive.
"It's an aqueduct bridge," Charles said. "Omega and Mother Ecos."
This wasn't a cavern at all, but part of a colossal pipeline, a fossil fragment of Mars's largest and last living things. I had never heard of an aqueduct bridge surviving intact.
"This section grew into the fissure about half a billion years ago. Loess and flopsand filled the branch because it ran counter to the prevailing winds. Cling and jetsand covered the aqueduct, but didn't stop it from pumping water to the south. When the Ecos failed and the water stopped, this part died along with all the other pipes, but it was protected. Come on."
Charles urged me deeper. We stepped around and under the internal supports for the vast organic pipe. Water once carried by this aqueduct had fed billions of hectares of green and purple lands, a natural irrigation system greater than anything humans had ever built.
These had been the true canals of Mars, but they had died long before they could have been seen by Schiaparelli or Percival Lowell.
I swallowed a lump in my throat. "It's beautiful," I said as we walked deeper. "Is it safe?"
"It's been here for five hundred million years," Charles said. "The walls are almost pure silica, built up in layers half a meter thick. I doubt it will fall on us now."
Light ghosted ahead. Charles paused for me to pick my way through a lattice of thick green-black filaments, then extended his arm for me to go first. My breath sounded harsh in the confines of the helmet.
"It's easier up ahead. Sandy floor, good walking."
The pipe opened onto a murky chamber. For a moment, I couldn't get any clear notion of size, but high above, a hole opened to black sky and I saw stars. The glow that diffused across the chamber came from a patch of golden sunlight gliding clockslow across the rippled sand floor.
 
; "It's a storage tank," Charles said. "And a pumping station. Kind of like Tres Haut Medoc."
"It's immense," I said.
"About fifty meters across. Not quite a sphere. The hole probably eroded through a few hundred years ago."
"Earth years."
"Right," he said, grinning.
I looked at the concentric ripples in the sand, imagining the puff and blow of the winds coming through the ceiling breach. I nudged loose dust and flop-sand with my boot. This went beyond confidence. Charles had guided me into genuine privilege, vouchsafed to very few. "I can't believe it."
"What?" Charles asked expectantly, pleased with himself.
I shrugged, unable to explain.
"I suppose eventually we'll bring in LitVid, maybe even open it to tourists," he said. "My father wanted it kept in the family for a few decades, but I don't think any of my aunts or uncles or the Klein BM managers agreed. They've kept it closed all these years in his memory, I suspect, but they think that's long enough, and there is the resource disclosure treaty to consider."
"Why did he want it closed?"
"He wanted to bring Klein kids here for a history lesson. Exclusively. Give them a sense of deep time."
Charles walked to the spot of sun and stood there, arms folded, his suit and helmet dazzling white and gold against the dull blue-green shadows beyond. He looked wonderfully arrogant, at home with eternity.
That sense of deep time Charles's father had coveted for his BM's children stole over me and brought on a bright, sparkling shock unlike anything I had ever experienced. My eyes adjusted to the gloom. Delicate traceries lined the glassy walls of the buried bubble. I remembered the paleoscape mural in Sean's hospital room. The natural cathedrals of Mars. All broken and flat now . . . except here.
I tried to imagine the godly calm of a planet where an immense, soap-bubble structure like this could remain undisturbed over hundreds of millions of years.
"Have you shown anybody else?" I asked.
"No," Charles said.
"I'm the first?"