Just before sunset yesterday, I left the dogs in the house and walked down the driveway to see if the paint had dried on the garage.  It was a still evening, no wind, and the acorns were falling steadily and noisily from every side.  I stood there in front of the garage, looking into the darkening forest, perking my ears up at the sound of falling acorns all around me.  The sky was still brightly lit from the rays of the setting sun.

Then another noise surrounded me - it sounded like the harsh panting of a very large animal.  My eyes scrambled through the trees, trying to find out where the sound was coming from, but everywhere I looked, no explanation showed itself.  The sound was even coming from above, my eyes following it.  A raven flew by overhead, his wings beating out the exact rhythm of the "heavy breathing" sound I was hearing.  He greeted me, I guess, with a single "grauk" and flew on, just above treetop level.  But the sound all around me persisted for almost a minute more.  Usually there are two ravens, so I thought maybe the sound around me was produced by more than one bird.  But I saw nothing else. 

I walked back to the house, marveling at how changed the entire atmosphere was by the passage of this amazing bird.  Mysterious, powerful creature; he had greeted me with his call as he passed.