He had passed visibly through two states and was entering upon a third. After his embarrassment and his unreasoning joy he was consumed with wonder at her presence. He had been full of the idea so long, dreamed it right through to the end, waited with his teeth set, so to speak, at an inconceivable pitch of intensity. Now, in the reaction, he was running down like an over-wound clock.
Chapter 5 · Narrator
Context
As the tour of Gatsby's house continues, Nick observes Gatsby entering a third emotional phase following embarrassment and joy. Gatsby appears overwhelmed by the reality of Daisy's presence after years of sustaining himself on fantasy alone.
Analysis
The simile of an 'over-wound clock' running down connects to the defunct mantelpiece clock earlier in the chapter, developing the motif of time as a mechanism that Gatsby has strained past its capacity—overwinding it with years of fantasy until the spring can no longer hold. The metaphor of having 'dreamed it right through to the end' is devastating in its implications: Gatsby has already consumed the entire narrative of his reunion in imagination, leaving no unexplored emotional territory for reality to occupy, which prefigures the inevitable diminishment Nick will observe moments later.
How to Use in Essay
Crucial for essays on how Gatsby's prolonged fantasy paradoxically diminishes the reality it was meant to prepare for, or for analyzing the novel's clock/time symbolism as representing desire that has exceeded its object's capacity to satisfy it.