Elsie pushed away the bed-clothes which were covering her ear, and listened; then she sat up in bed, and listened again. There was no doubt that it was an actual sound, and not mere imagination. How long it had been going on, or when it first began to mingle in a confused manner with her dreams, she could not say; but now she heard it plainly enough, and recognized what it was-the peculiar, grating hiss of a grindstone, punctuated every now and then with a subdued little squeak made by the treadle.