Kit Whitfield has an ongoing series of blog posts in which she deconstructs first sentences. Here she is on Five Children and It, The Haunting of Hill House, and Brave New World:

Most obvious is the mimicry: thirty-four storeys merits an 'only'? The image is at once visual and conceptual, pulling us with delicate uncertainty between the two. Is it called 'squat' because the narrative voice, or at least the characters it invokes, judges entirely on its lack of floors - that is, does the building look like a contemporary skyscraper? (Brave New World was first published in 1932; New York had been able to boast of the Chrysler and Empire State Buildings for a couple of decades, making them a feature of life well placed to occupy speculative fiction: new enough to be notable, old enough to be familiar to everyone.) Or is it thirty-four storeys high and still squat judged by contemporary proportions? The former invokes a city of mountainous needles reaching into the sky; the latter a city with buildings of gargantuan size - and in both cases, a rather sterile and ugly place where the buildings are grey and unattractive. Either is an environment calculated to daunt even the most forward-looking reader: overbearingly urban, utterly out of human scale ... and yet populated by people who can be expected to shrug off this mammoth edifice as nothing much.