The Wendigo — Algernon Blackwood

The sound dropped upon him out of that still, wintry sky with an effect of dismay and terror unsurpassed. The rifle fell to his feet. He stood motionless an instant, listening as it were with his whole body, then staggered back against the nearest tree for support, disorganized hopelessly in mind and spirit. To him, in that moment, it seemed the most shattering and dislocating experience he had ever known, so that his heart emptied itself of all feeling whatsoever as by a sudden draught.