Time is not experienced conventionally in To the Lighthouse (but seriously, what is?). Instead, time is anchored in certain select moments, which completely distorts it from the way a clock experiences time. Time is measured as it is experienced by certain people, which infuses select moments with incredible importance and duration. In other parts of the novel, ten years is covered in about a dozen pages. Time is therefore both elongated and compressed.
Part Two of the novel, "Time Passes," is the only portion of the novel we see what the characters are so concerned with – the destructiveness of time.