In which line is the hint to the location of the first act?

We're already told the location of the play in the introductory stage notes—"Act One: The Terrace of a Hotel in France. Summer evening." However, even if we overlook the stage notes, we can still pick up one or two hints of the play's location in the opening act. Elyot tells an astonished Sibyl that he wants them to leave immediately, even though they've only just arrived at the hotel and unpacked. He wants them to have their first night together in Paris. Sibyl implies that this would be impossible in any case, as they'd only reach Paris in the early hours of the next morning. Given that it's evening, this would suggest that the couple are indeed in France. Anyway, Elyot's insistent that he and Sibyl should leave at once, not least because he thinks there might be some kind of earthquake in the offing. Sibyl replies that they don't have earthquakes in France, indicating once more where the action's taking place.