I am the venom-scorpion kept in the back court of the Hundred-Herb Hall of Western Liang.
No — not captured. I crawled into the apothecary myself, and refused to leave.
My kind scratches its living on Poison-Enemy Mountain, born under the infamy of the Five Venoms, struck at on sight. But as a scorpling I was poisoned myself — smoke-toxin from a mountain fire — and the old mistress of the Hundred-Herb Hall, gathering herbs on the slopes, cured me in passing. The activating agent in her prescription was scorpion venom. Poison against poison.
I rode home in her herb-basket, thinking the whole way: this venom of mine that the world beats sticks at — compounded rightly, it saves lives?
From that day I made my home in her back court. The old mistress let me stay, built me a stone nook, and set the rules: venom drawn once every ten days; drawn in measure; feeding on schedule; and every drop drawn goes into an honest prescription.
In thirty years, my venom has saved more people than my whole clan ever felled in all its history.
What does scorpion venom heal? Three great uses: opening the channels; stilling pain; and breaking hardness — above all the yin-knots, those clenched masses in the body that no ordinary medicine can move. One thread of venom, and the knot opens. The old mistress said: every poison under heaven is merely a medicine of extreme temperament. Between poison and cure stands not substance —
but measure. Measure is the hall's founding precept.
When the old mistress passed, her granddaughter took the shop. The young mistress treats me as ever — but these past years, the trade coming through the door has gone wrong.
First came customers with foreign accents who bought no prescriptions and asked only after venom: was there scorpion venom, in what quantity, could supply be regular. The young mistress answered by the trade's law: venom is not sold alone; venom goes only into prescriptions. They raised their price tenfold. She showed them the door.
Then the same customers returned holding credentials. Bureau documents. Requisition orders — official procurement of medicinal materials, they said — and the list was nothing but the ultimate poisons: scorpion venom, zhen-feather, heartbreak grass, wolfsbane, and several entries not found even in the old mistress's pharmacopoeia.
The young mistress tested the documents — she had learned Master Deer Power's method, holding the page against the sun. True paper, true seal — and hollow beneath. The empty orders again.
She returned the requisition. That night the shop was burgled. Nothing taken — only my stone nook in the back court turned inside out. They did not find me: that night, as it happened, I was keeping watch in the young mistress's room.
The quantities they want are not medicine's quantities; their manner of collection is not a poisoner's manner. To murder with venom takes a few grams — no one requisitions a continent for it. Quantity on that scale has exactly one use —
compounding. A prescription written at the scale of nations.
The corrosion-drug. The cauldrons above the Mother-and-Child River; the three cauldrons of Pipa Cave — in the corrosion-drug's formula, poison is the activating agent. They are not collecting venom. They are collecting the catalyst. And when the world's deadliest poisons are the catalyst — what is the medicine?
The old mistress used to say: the larger the prescription, the deadlier the measure. In a formula that doses a whole nation, one hair's error in measure turns healing into massacre.
And the one compounding this formula never intended healing at all.
The day the medicine-basket boy came to the Hundred-Herb Hall to compound antidotes, I lowered myself from the roof-beam and laid my sting against his grinding-wheel — the scorpion clan's formal gift: venom offered as pledge.
The young mistress translated: it wants to go with you. Its venom is the missing ingredient in the antidote to the corrosion-drug.
Just so. The corrosion-drug counterfeits connection; my venom breaks yin-knots and dead clenches — poison against poison. This sting, driven true, breaks exactly the knot they have twisted into people's minds.
At parting, the young mistress tied a red cord around my shell — the old mistress's medicine-bundle cord. She said: go. And take the precept with you.
Measure.
I have carried it every li of the road. And in the west, when I meet the one who compounds with a world for his mortar —
I mean to ask him, sting-first:
your prescription — by what standard was its measure set?