Before we talk about style, go read the section on "Narrator Point of View."
Back? OK, so remember how the Time Traveller will tell us a lot of stuff he got wrong before he tells us the real deal? For instance, he tells us he thought the strange wells were part of the Eloi's sanitation system, and only later does he tell us that the wells are actually the way the Morlocks get to the surface to hunt. He's telling us this story after he learned the truth, so we can be sure that when he's keeping us in the dark, it's intentional.
With that in mind, check out the first sentence of the book:
The Time Traveller (for so it will be convenient to speak of him) was expounding a recondite matter to us. (1.1)
What can we say about that sentence? First, we might say that it leaves out a lot. Assuming we even know what "recondite" means (it means difficult or obscure) what is the "matter" in question? Who is meant by "us"? What was the Time Traveller's actual name?
After reading the first chapter, we could rewrite that sentence – and let's give the Time Traveller a name just to make it simple:
Herbert [the Time Traveller] was explaining time travel [the "recondite matter"] to his dinner guests ["us"].
Instead of making things clear up front, Wells makes us wait to get all the information we need. So the style of the novel makes us wait, just like the narrative point of view does.
Second, check out the delay between "The Time Traveller" and "was expounding." Isn't that a bit of a pain to read? Usually a sentence is easier to read when the subject and the verb are together. In our simple rewrite above, we got around the issue by dropping the whole "for so it will be convenient to speak of him." But we could keep that in and simply move it to a new sentence:
It will be convenient to speak of our host as the Time Traveller. The Time Traveller was expounding a recondite matter to us.
Ta-da! It's possible to rewrite the sentence to prevent the delay between the subject and the verb, which means the delay is purposeful.
So it seems there are two ways to delay: 1) withhold the info (what's the "recondite matter"?); 2) interrupt our reading process. But what does that delay do to us as readers? Does it create suspense? Does it make us want to keep reading? We don't have a definite answer – what do you think?
Just when you might be ready to throw the book and its delaying tactics across the room, we get to a simple sentence like this:
She was exactly like a child. (5.24)
The next night I did not sleep well. (6.2)
After slogging through so many long sentences, those brief, clear sentences come as a relief. We could rewrite them to them more convoluted, e.g. "Weena – with her carelessness, innocence, and grace – exhibited all of the traits characteristic of a young child." So these sentences must be simple on purpose. But why?