Terminal Velocity

"Sheila! Sheila! Where are you? Come on back, dummy!"

He was walking in the woods. Ostensibly with his dog. But she had vanished. All alone in a big park, he'd judged it safe to let her off the leash, and she'd seemed grateful, tearing around joyfully, big dumb happy tongue lolling. But now she seemed to have followed a squirrel right on out of the area; he couldn't hear any sign of her now, no rustling or barking or horselike footfalls. (She was a Rottweiler/Great Dane mix....)

After several minutes of calling, he finally heard her coming back his way. By this point, he had walked into a narrow ravine cut into a hillside, whether by nature or park rangers he didn't know, that allowed hikers to descend to the river valley below. And, over the hill the dog came. At top speed.

WHAM

When the world rebooted, he found he was on his back, looking up at the autumn leaves. His glasses didn't seem to be on his face, so they looked impressionistic, floating before his eyeballs in daubed smears of reds and yellows. Hot doggy breath wafted across his cheek. Sheila looked puzzled to see him on his back, when he was usually such an upright guy.