欄空童睡 The Pen Empty, the Boy Asleep
行者入裡，眼不轉睛，東張西看。走過幾層廊宇，忽見那牛欄邊一個童兒盹睡，青牛不在欄中。行者道：「老官，走了牛也，走了牛也。」老君大驚道：「這孽畜幾時走了？」正嚷間，那童兒方醒，跪於當面道：「爺爺，弟子睡著，不知是幾時走的。」老君罵道：「你這廝如何盹睡？」童兒叩頭道：「弟子在丹房裡拾得一粒丹，當時吃了，就在此睡著。」老君道：「想是前日煉的七返火丹，吊了一粒，被這廝拾吃了。那丹吃一粒，該睡七日哩。那孽畜因你睡著，無人看管，遂乘機走下界去，今亦是七日矣。」行者入里，眼不转睛，东张西看。走过几层廊宇，忽见那牛栏边一个童儿盹睡，青牛不在栏中。行者道：「老官，走了牛也，走了牛也。」老君大惊道：「这孽畜几时走了？」正嚷间，那童儿方醒，跪于当面道：「爷爷，弟子睡着，不知是几时走的。」老君骂道：「你这厮如何盹睡？」童儿叩头道：「弟子在丹房里拾得一粒丹，当时吃了，就在此睡着。」老君道：「想是前日炼的七返火丹，吊了一粒，被这厮拾吃了。那丹吃一粒，该睡七日哩。那孽畜因你睡着，无人看管，遂乘机走下界去，今亦是七日矣。」
逐句解 Line by line
Pilgrim went inside, his eyes never still, looking east and west.
東張西看: 看 = kàn. 眼不轉睛 = "his eyeballs never turned aside," i.e. he missed nothing.
He passed through several ranges of galleries, and suddenly saw, beside the ox-pen, a boy dozing — and no blue ox in the pen.
Deictic 那牛欄: 那 = nà; 童兒: 兒 = er; 欄中: 中 = zhōng. Two clauses, and the mystery of three chapters is solved.
Pilgrim said: "Old fellow, your ox has got out! Your ox has got out!"
Both 了 = le, positional. He does not accuse; he reports, with the relish of a man who has just been told there was nothing to find here.
Lord Lao was greatly startled: "When did the accursed beast get out?"
孽畜: 畜 = chù; 走了: 了 = le. He uses the same word for his ox that Pilgrim and the demon-king have been throwing at each other all chapter.
Amid the shouting the boy woke at last, and knelt where he was: "Grandfather, your disciple was asleep. I do not know when it got out."
正嚷間: 間 = jiān; deictic 那童兒: 那 = nà, 兒 = er; 當面: 當 = dāng; 弟子: 子 = zǐ; 睡著: 著 = zháo, resultative.
Lord Lao cursed him: "You wretch, how came you to be dozing?"
這廝 is contemptuous — "this fellow, this creature." The whole catastrophe of three chapters is now a matter of household discipline.
The boy knocked his head on the ground: "Your disciple picked up a pill in the elixir chamber, and ate it there and then, and fell asleep here."
童兒: 兒 = er; 弟子: 子 = zǐ; 拾得: 得 = dé; 當時: 當 = dāng; 吃了: 了 = le; 睡著: 著 = zháo.
Lord Lao said: "It must have been the seven-returns fire elixir I refined the other day. A pill was dropped, and this wretch picked it up and ate it.
煉的: 的 = de; both 了 = le, positional. 七返火丹 — the elixir of the seven cyclical reversions, from the vocabulary of outer alchemy.
"One pill of that elixir means seven days' sleep.
Deictic 那丹: 那 = nà; sentence-final 哩 = li. The dose and the duration are stated as flatly as a pharmacist would state them.
"The accursed beast, with you asleep and nobody minding him, took his chance and went down to the world below — and today makes seven days."
看管: 看 = kān ("to mind, to keep watch over"), the tending reading, not kàn. 乘機: 乘 = chéng — the only occurrence in the chapter, and it overturns the cumulative table's invariant shèng. 睡著: 著 = zháo; 孽畜: 畜 = chù.
Two clauses undo three chapters. Pilgrim walks past the galleries, sees a boy dozing beside an ox-pen and no ox in it, and everything that has happened since Chapter 50 acquires a cause: a servant picked up a dropped pill, ate it, and slept. The novel gives the mechanism with a pharmacist's precision — one pill, seven days' sleep, and today makes seven — and the arithmetic is exact. The demon who has taken the cudgel, the six celestial weapons, the fire-armoury, the Water Earl's flood and eighteen grains of the Buddha's golden sand got out because nobody was minding the gate.
The deflation is total and the narrator does nothing to soften it. The being who has defeated the celestial army, the Fire and Water Departments and the arhats of Vulture Peak is, in this room, 孽畜 — the accursed beast — the same term Pilgrim and the demon have been hurling at each other for two chapters, now used by his owner in the tone of a man whose livestock has strayed. There is no malice anywhere in the causal chain: no plot against the pilgrims, no rebellion, not even a decision. A pill was dropped and a boy was greedy.