Thoreau writes in his journal:
As when Antmus touched the earth, so when the mountaineer scents the fern, he bounds up like a chamois, or mountain goat, with renewed strength. There is no French perfumery about it. It has not been tampered with by any perfumer to their majesties. It is the fragrance of those plants whose impressions we see on our coal. Beware of the cultivation that eradicates it . . .