farmer, who from far through the woods sought my house, to have a
social "crack"; one of the few of his vocation who are "men on their
farms"; who donned a frock instead of a professor's gown, and is as
ready to extract the moral out of church or state as to haul a load of
manure from his barn-yard. — Thoreau, Walden.
Reading Walden via the excellent email reading service DailyLit, I googled cronching which yielded 1160 hits, mostly misspellings, nicknames, and discussions of this very neologism, so Thoreau's invention which didn't catch on. Still, is there a more perfect word for the sound of snow packing underfoot by a winter hiker's approach? Thoreau's a wondeful writer.
(One interesting hit came up to the Chicago Manual of Style Online, which uses this sentence from Walden as an example of how to use the term "sic.")