I heard a sharp click as Holmes cocked his pistol.  There was a thin,
crisp, continuous patter from somewhere in the heart of that crawling
bank.  The cloud was within fifty yard of us, and we glared at it, 
uncertain what horror was about to break out.  Holmes's face was pale &
exultant, his eyes shining brightly in the moonlight. Suddenly they 
started forward in a rigid, fixed stare, and his lips parted in amazement.
At the same instant, Lestrade gave a yell of terror and threw himself 
face downward upon the ground.  I sprang to my feet, my inert hand 
grasping my pistol, my mind paralyzed by the dreadful shape which had 
sprung out upon us from the shadows of the fog. A hound it was, an 
enormous coal-black hound, but not such a hound as mortal eyes had ever 
seen. Fire burst from its open mouth, its eyes glowed with a smouldering
glare, its muzzle & hackles & dewlap were outlined in flickering flame. 
