A red and black image of a demon with large wings

It was like a great shadow, in the middle of which was a dark form, of man-shape maybe, yet greater; and a power and terror seemed to be in it and to go before it. A figure strode to the fissure, no more than man-high yet terror seemed to go before it. They could see the furnace-fire of its eyes from afar; its arms were very long; it had a red [?tongue]. It came to the edge of the fire and the light faded as if a cloud had bent over it. [...] The flames roared up to greet it, and wreathed about it; and a black smoke swirled in the air. Its streaming mane kindled, and blazed behind it. In its right hand was a blade like a stabbing tongue of fire; in its left it held a whip of many thongs.