Pint-sized Quixote

''A pond was here,'' Tyler pronounced. His hand was swallowed in mine. His short legs plowed forward with confidence.

''How do you know?'' I challenged.

''Because there's this dent. Didn't you see it?'' He stopped, turned, and pointed it out.

''Yes,'' I said, ''now I do.'' There was a blur of green over the dark moist shallow; grass roots quickened from last weekend's rain.

To most, a puddle, a mud-depression; to Tyler, however, nothing less than a pond. Complete with reeds, frogs, pennybugs - why not? - little fish. Perspective I honor. Imagination: what poet wouldn't respect? He stepped to the side of the path, garnered a black feather. ''From a crow's tail,'' I said. ''It's a wing feather,'' he corrected. ''Don't you see it's all curved to one side?''

''You're right. A crow's wing feather.''

''It's from a phoenix,'' he patiently corrected. How could a grandmother be so prosaic? The same grandmother who first acquainted him with phoenixes. Though his tone was mild, I saw fire flash from his brown eyes. Flame enveloped, consumed the dull feather. Reborn in soot, it pulsed in his hand.

We advanced to a paved strip where a narrow bridge spanned the brook. Halfway through a hop-skip he paused. ''Who cracked the road?''

''Frost?''

He considered. ''No, Gocky. A herd of elephants. They went by yesterday night. Didn't you hear their thunder?''

He picked up a leached stick. In a worm hole he stuck the black phoenix feather, then flung it into the water. It snagged, bumped against the near bank, whirled in an eddy and righted itself for a clear sail. ''What's your ship's name?'' I asked while we watched.

''Does it have to have a name, Gocky? OK.'' He sighed. ''You want to think of one?''

I seriously considered. ''The Pee-Wee?''

He shrugged. ''Big Chief,'' he decided. ''Neat-o?''

I, fearful of turning into a pillar of salt, refrained from reporting what I'd witnessed on a last look back. The weighted craft arched over a small rapids , capsized and shattered against a rock. Only the feather escaped and floated on.

Ty was ahead of me, breasting the tall green grasses. Below, the stream washed on, dividing as it came to a small, overgrown island. There, amid protective rushes, I spotted a motionless least bittern. The bird stood on one foot, beak pointed skyward - for all the world resembling the wet jungle growth from which it hunted and which, in turn, hid him. Clutching the child back, I whispered my discovery. ''What bittern?'' he said loftily. ''That's my pet unicorn.''

Almost too much - even from the four-year-old I'm sponsoring. ''That,'' I said firmly, seeing a need to reclaim my position in the hierarchy, ''is a bird. By no stretch of your imagination can it be a mythical beast.''

He traced the vertical beak on the air under my nose. ''Can't you see his horn, Gocky? One straight horn. Don't worry. He's my friend. He won't hurt anybody.'' He put a cautionary finger to his mouth, took my hand and tiptoed me back from the water's edge. ''He's dreaming right now. Nobody's s'posed to disturb him. That's how it is with unicorns, don't you remember?''

I kicked a stone that tumbled down the bank, making a slight splash, ringing out to the magic isle. The green bittern never stirred - only blinked a unicorn-eye and held its poise. If not for that, I'd have vouched it was transfixed.

As we went up the path toward home Ty pulled me every way, holding my hand, stretching our connection as he leaped Grand Canyon washouts, dry and rock strewn. Uphill all the way, tireless, he jumped across ruts and back, while I puffed alongside, trying to keep abreast. Phoenixes and Indian chiefs, unicorns and Grand Canyons, Dead Sea scrolls and what-not were in his path. Tomorrow - all uphill - and exciting. I, in his dancing shadow, was renewed.