And this was the mountain:

Four characters, and the cue is carried inside them rather than standing apart, so this line opens the poem rather than announcing it. The next showcase in this same stretch does it the other way round, which is the novel keeping both options open.

Wind soughing in the woods; water purling at the gully floor.

The mountain arrives as noise before it arrives as anything else. 颯颯 and 潺潺 are doubled sound-words in matching positions, wind against water, and the second of them carries the poem's rhyme. Both keep their ordinary readings: the house rule is that a pair of echoing syllables like these gets no special treatment unless a dictionary records one.

Crow and sparrow cannot get across it; even an immortal calls it hard.

A standard escalation, and an efficient one. If the birds cannot get over it and the immortals admit it is hard, the men on foot are in trouble. 道 is the verb here, to say, not the noun that means the Way.

A thousand cliffs, ten thousand ravines; a hundred million turns, a hundred bends.

Four numbers in eight characters, and they refuse to climb: thousand, ten thousand, hundred million, then a hundred. That last drop is deliberate — the couplet ends on the small tight turn of the path rather than on the size of the range, which is the detail that actually matters to somebody walking it.

Dust rolling on and on, and nobody comes; strange rocks ranked thick, and one never tires of the sight.

看 reads kān, in the level tone, and the poem's own sound is what settles it: all eight of its rhyme words are level, and kàn would be the single exception. The Kāngxī dictionary agrees, leading with 苦寒切 from the 唐韻 and 丘寒切 from the 集韻, both giving kān, and putting the falling-tone spelling 苦旰切 second; it even records a rhyme-adjusted reading of the character in an old poem, which is the same problem being solved the same way a thousand years earlier.

Wherever there is a hollow there is cloud, rocking like water; wherever there is ground there is a tree, thick with birdsong.

The same construction twice, 有處有 and 是方是, both meaning every place where — the poem's way of saying it is like this all over. 滉 is water swaying in a vessel, so the cloud is not drifting between the peaks so much as slopping about in them.

A deer carries the magic fungus off; a gibbon picks a peach and comes back.

Both halves are pictures of immortality being carried around by animals with no use for it. 芝 is the fungus of long life and the peach is the other great emblem of it, and the two verbs are set against each other as well: one beast leaves, the other comes back.

Fox and raccoon dog come and go, springing along the cliff; big deer and river deer pass in and out, romping on the ridge-crest.

狐貉 is the old paired name for the two animals whose pelts were worn together, which is why they arrive as a set. 貉 reads hé: the Kāngxī dictionary gives 曷各切 and 下各切, two spellings of one reading, and a separate 莫白切 used only for the name of a northern people. The háo of everyday speech answers to nothing in the entry at all.

Then a tiger's roar to shake the gall; striped leopard and grey wolf barring the road.

Seven couplets without a threat in any of them, and then the last one turns predatory. 把路攔 is flat vernacular dropped in after all that balanced description, and it hands the story straight back to the prose, where Tripitaka is already frightened.