Gollum looked at them. A strange expression passed over his lean
hungry face. The gleam faded from his eyes, and they went dim and grey, old and
tired. A spasm of pain seemed to twist him, and he turned away, peering back up
towards the pass, shaking his head, as if engaged in some interior debate. Then
he came back, and slowly putting out a trembling hand, very cautiously he
touched Frodo's knee – but almost the touch was a caress. For a fleeting
moment, could one of the sleepers have seen him, they would have thought that
they beheld an old weary hobbit, shrunken by the years that had carried him far
beyond his time, beyond friends and kin, and the fields and streams of youth,
an old starved pitiable thing.
(TT 4.viii.714)
This paragraph is so remarkable rhetorically that examining it in great detail will repay the effort. Let's take it a sentence at a time.
1. Gollum looked at them. (4)
2. A strange expression passed over his lean hungry face.(9)
3. The gleam faded from his eyes, and they went dim and grey, old and tired. (15)
4. A spasm of pain seemed to twist him, and he turned away, peering back up towards the pass, shaking his head, as if engaged in some interior debate. (28)
5. Then he came back, and slowly putting out a trembling hand, very cautiously he touched Frodo's knee – but almost the touch was a caress. (24)
6. For a fleeting moment, could one of the sleepers have seen him, they would have thought that they beheld an old weary hobbit, shrunken by the years that had carried him far beyond his time, beyond friends and kin, and the fields and streams of youth, an old starved pitiable thing.(51)
By separating the sentences as I have done, something becomes immediately clear even without counting the words. Five sentences out of the six are significantly longer than the sentences before them. But the sentences do not just get longer. They become more complicated.
The first sentence has a subject, a verb, and a prepositional phrase. The second has the same structure, but by the addition of two adjectives it evokes an archetypal figure of treachery to a benefactor -- 'Yon Cassius has a lean and hungry look' (Shakespeare, Julius Caesar 1.2.195). The third sentence begins exactly as the first two did (subject, verb, prepositional phrase), but adds a second coordinate clause, with four adjectives in rhythmic alliterative pairs to expand upon the first clause. In doing so, the third sentence answers the suggestion of the second: Gollum's lightless eyes reveal only weariness and age.
The fourth sentence is not just compound, but in its second part becomes complex, using three subordinate clauses ('peering...shaking...as if....') to illuminate the action of its first half. It anticipates the betrayal the reader knows is coming and seems to recapitulate silently the debate Sam overheard in the Dead Marshes.
'Then he came back’, the first four words of the fifth sentence, act like a hinge at the paragraph's center, pivoting the Tale away from treachery, and towards the repentance if not the redemption, which the complex, heavily modified second clause and the blunt, breathtaking third declare to be possible at this instant. The dash before 'but' and the emphatic displacement of 'almost' draw the reader's attention like a manicule to the difference between the 'caress' of Gollum's 'trembling hand' here and the 'long fingers flexed and twitching, claw[ing] towards [Frodo's] neck' at the end of the earlier debate (TT 4.ii.634). Here, too, the betrayal hinted at by the 'interior debate' of the fourth sentence is answered by the 'almost the touch was a caress'.
The sixth sentence sweeps up all the long years of Gollum's life into one astonishingly poignant 'fleeting moment'. It depicts that moment for the reader by means of an exceptionally long and complex sentence in the form of a condition contrary to fact. It imagines a circumstance which did not arise and a sight which was not seen, except by the reader; and yet the reader's vision of Gollum here, echoing Bilbo's vision of Gollum in The Hobbit, feels right and true. Recall that the narrator of The Lord of the Rings is usually Frodo and sometimes Sam, not some omniscient third person. As the narrator tells us, they were both asleep. How then can the reader see this if they did not? (A fascinating question I will address elsewhere.) For the moment we will content ourselves with the thought that the prose here is so rhetorically powerful that it can persuade the readers that they have seen something which, except for the last gesture, no one in the book could have seen or told of.
__________
Here are a few nice touches to be found in this paragraph.
The first word is 'Gollum', and the last is 'thing', which in apposition with 'hobbit'.
Saying that Gollum was 'shrunken' by the years might be meant to call to mind the Cumaean Sibyl, who shrank as she lived on and on without dying.
The last four words -- 'old starved pitiable thing' -- may be scanned as a spondee, a dactyl, and a spondee, which gives a nice, rhythmic ending to the paragraph, a trick of ancient rhetoric Tolkien will have learned in school.
