How do the descriptions of Gatsby at the beginning of chapter 1 differ from the end of chapter 1?

In the beginning of the first chapter, Nick's descriptions of Gatsby concern intangibles and abstractions: general descriptions about him as a person (and even a victim). However, at the end of the chapter, Nick describes Gatsby's actual movements and physicality from a real moment. Early in the chapter, Nick says that there is "something gorgeous" about Gatsby, "some heightened sensitivity to the promises of life, as if he were related to one of those intricate machines that register earthquakes ten thousand miles away." Gatsby, he says, has a certain kind of hopefulness; the man possesses a "romantic readiness" that Nick finds incredibly singular and unlike any other person he's ever met. He also describes Gatsby as a kind of "prey," and he does so in the past tense, giving us a clue as to Gatsby's future. At the end of the chapter, however, Nick describes Gatsby's "leisurely movements and the secure position of his feet upon the lawn" which seem to suggest that he'd come outside "to determine what share was his of our local heavens." Suddenly, Gatsby "stretched out his arms toward the dark water in a curious way" while he seemed to tremble. Nick sees that Gatsby seems to be reaching out toward a single green light across the bay.