Achiral

Milk

The first thing I ever made for my daughter was her milk.

I don’t mean expressed. I mean made: four hundred litres of it across two years, synthesised in the food wing from carbon, ammonia and power, every molecule assembled the wrong way round — which is to say, assembled for her. Lactose that would pass through my body like a rumour. Proteins wound against the thread of everything I am.

This world was generous by every measure taken from orbit: liquid water, oxygen, a biosphere four billion years old. The survey noted one small thing, and nobody on the ship felt it until we landed and were hungry. Life here runs the same chemistry we do, in a mirror. Its proteins twist the way ours don’t; its sugars likewise. Nothing here is poison to us — I want to be exact, because poison is what people assume, and poison would at least be a relationship. A native fruit is not a threat. It is a rumour of food. You can eat it all day and starve.

There were eleven hundred of us, and every calorie came out of the grow-halls: washed gravel, lamplight, seed the ship had carried frozen. The honest audit gave the halls sixty years. Outside the halls — outside nothing; we could walk bare-faced under the sky, and the world’s diseases could no more touch us than its dinners could — outside lay an open country that would not feed us.

So the vote, taken twice, two years apart, both times carrying: not to remake the planet for the children, but the children for the planet. A mirrored genome. Mirrored flora for the gut, grown in the same tanks. Mirrored wheat and mirrored barley, resynthesised from the ship’s libraries, to be sown in living soil. The children would eat the world.

A mirrored child cannot be carried. A placenta is a customs house; it hands across sugars, and mine would have been nothing to her. So my daughter grew in a tank that I could put my arms around, but not around her, and the first thing I ever did for her was chemistry.

The consent form had a space for the subject’s name. The subject would not exist for another year. We named a hypothesis, and the hypothesis was Ruth.

There was a counsellor, and a sentence she was required to read exactly as written: You understand that your daughter will be able to have children with the other mirrored children, and with no one else, ever. I signed. A species is not a grand thing. It is a door that shuts.

Bread

For her first five years, Ruth’s food cost more than the rest of the colony’s put together, every gram of it synthesised the way her milk had been. Then the mirror fields at the river came into bearing, and her bread cost sunlight, the way bread should.

We kept two of everything in the kitchen — two pans, two boards, two crocks of flour — not for safety, because there is no danger in either direction, but because it is hard to teach a child that some food is hers and some is only a picture of food. She sorted it younger than she sorted colours. Hers and mine. The two kingdoms, one shelf apart.

She baked her first loaf at nine and made me eat a slice, and I did, and she watched my face the whole time.

“It’s just bread, Mum. You don’t have to every time.”

I did have to. It tasted the way bread tastes in a dream: sweet, and vague, and gone. Her sugars still sit down on my tongue — sweetness, it turns out, is an easy lock, and the wrong-handed key half-turns it — they simply go no further than the tongue. Her savours don’t make the crossing at all. Everything my daughter has ever cooked me tastes faintly sweet, and nothing she has ever cooked me tastes of meat.

There is one amino acid with no handedness — glycine, the smallest, a bare hydrogen where the twist would be. It is the only piece of protein her body and mine hold in common, the one word spelled the same in both scripts, and what it tastes of is sweet.

Mint

They gave the mirrored cohort the open country in the spring Ruth turned fourteen: the river terraces, the long field, the slopes nobody had ever bothered to name because nobody could use them. We could all of us always walk there; that was never the division. The division was that she could kneel at the field edge, pull a stem, and eat it.

She grew mint in a border by the gate — mirror mint, rebuilt from Earth stock like the barley. To her it is spearmint. To me that same leaf smells of caraway: one molecule, and we hold it by opposite ends. She used to make me smell it every visit, delighted, as if the leaf were doing a trick. It was doing a trick. It has never once stopped doing it.

I carried my own tin to her harvest festivals for years, and nobody thought it odd. Half the parents on the terrace were doing the same: a generation of us eating packed lunches from the grow-halls at the edge of our children’s abundance, watching them come up the rows with their arms full.

Fever

Chemistry opens a door; it took eleven years for anything local to walk through it. The mirror children were compatible with this biosphere from their first breath, but compatibility is only an address — it took that long for some small native thing to learn the way to the house. Ruth was seventeen, and for nine days she burned.

The ward sister offered me a mask at the door, out of habit. There is no mask to want. Her illness could not cross to me; nothing of hers can cross to me. I sat with her four nights running and was never once in danger, and I have not forgiven that.

She recovered. Most of them did, that first season; our medicine had learned to read mirror blood by then, even if our bodies never would. But the ledger was open now and everyone could read it. The price of eating a biosphere is being food for one.

Salt

Ruth carried her own daughter. That door, which shut on my side of the mirror, stands open on hers, and she walked through it the ordinary way, complaining about her back. No tanks. No synthesis wing. Her body handed its sugars across the customs house to a child who could use every one of them.

She put my granddaughter in my arms an hour old, and the weight was the weight — the same warm heft that has not changed since the Pleistocene, going down the line the way it always has, one pair of arms to the next.

At the naming I cried, which I had promised her I wouldn’t. Ruth took my hand and then her own eyes went, and where our fingers were folded together the tears ran in and could not be told apart. Salt crosses. Water crosses. In the fold of our hands it was all one brine.

Spirit

The distillery was Ruth’s idea. She came to the flat with the first bottle herself, holding it out with both hands like something rescued.

“You can actually drink this one,” she said. “It’s from the long field.”

Ethanol is too small a molecule to own a hand. Ferment her grain — call it barley; it is what barley becomes when you rebuild it in a mirror and give it a new world — and what comes over the condenser is the same spirit, atom for atom, as anything ever drunk on Earth. Her yeast eats sugars I will never taste and hands me back something my body knows the whole way down.

We have a rule now, she and I, for the long evenings: one bottle, two glasses. What crosses between us: water, salt, spirit. It is not enough to live on. We raise our glasses anyway, and for as long as the warmth lasts we are fed from the same field.