He showed that the average individual's sleep cycle is punctuated with peculiar bursts of eye-movements, some drifting and slow, others jerky and rapid.
Every now and then during the next half mile, little gusts of stinging snowflakes whirled down from the sky, beat against their faces, and scurried on.
Maybe he was imagining it, maybe not, but he thought a faint whispering was coming from the books, as though they knew someone was there who shouldn't be.