The steam didn't look a whole lot different in the scorching fever of the hottest July than it had six months before, in the coldest February.

It was a little lower, for sure, but otherwise the cool, milky water of Falling Spring in southern Pennsylvania doesn't despond much to earthly ups and downs.

It's spring-fed and tempered by the limestone beds from which it emerges. Falling Spring never freezes, so in the dead of winter it burbles through snow-covered meadows, steam rising from the riffles and pools. And in summer it stays cool and clear.

Clear enough, in fact, that the brown and rainbow trout that make it a must-stop for serious fly fishermen are almost surrealistically visible. They rest in the deep pools and channels, waiting for bugs to float by, and they race for cover when clumsy anglers disturb their peace.

Falling Spring is one of several spectacular trout streams that the Pennsylvania Fish Commission, in its exemplary wisdom, has set aside as a fish-for-fun area.

That means only one fish over 18 inches may be kept per day, per angler, if anyone's lucky enough to get one, and only fly fishing is permitted. Because of these stringent rules there are and apparently always will be hundreds of trout waiting in the little stream off 181 and Route 30 near chambersburg.

But they're smart, spooky and hard to get to.

Falling Spring is nothing but a divinely blessed pasture creek. One fishes from weed-choked banks into weed-choked waters. There are a million-and-one ways to get tangled, not the least likely of which is to catch your fly on the hide of a grazing cow while back-casting. That actually happened on Thursday - the line snapped, the cow mooed and walked away with a No. 20 hook firmly imbedded in its posterior.

But catching a cow is not the point, though it would be simpler if it were. The point is trout and they are not so easily hooked.

In these dog days of summer the only hatch of any consequence at Falling Spring is of triclorythodes (caenis) flies, little bitty mayflies that pop off the water early in the day. It was so hot Thursday that they hatched before we could get there. The trout had slurped up what flies there were and by 11 a.m. were resting warily in the rushing waters, waiting for terrestrials.

Terrestrials are ants, beetles, spiders and other landlubber bugs that are only attacked when they make the mistake of falling in the trout water.

Our selected teasers were hand-tied beetles, black deer hair bugs that would dance through the riffles and float in the quiet pools.

The idea is to find a trout you want, the bigger the better, then sneak up from downstream, plunk the beetle just ahead of its line of sight and let it drift back in the current. The trout should rise to the fly, one of th sweetest victories and angler can know.

And one of the most difficult. These trout are thoroughly fished over and they don't stay stupid for long, if they ever were. They can spot a phony bug before it hits the water; a clumsy presentation of even the finest fake beetle sends them scurrying to the weeds.

Which is why, after four hours, I was still looking for my first chance to unhook a trophy at stream's edge.

Footsore and weary, wet from a thunderstorm, feet mired in mud and cow flop, I was approaching with resignation the black pool my partner had suggested as the last good hope for the day. He had already collared six fish.

I tiptoed along, 15 feet from the edge, working channels with eyes shaded by polarized sunglasses. Suddenly he was there 10 feet out, working lazily along a channel edge; a 16-inch male brown trout, the best I'd seen all day.

And he was accessible; no trees or cows behind, no weeds in front; he was in clear water.

The bug dropped, plop, on the rushing water. It drifted slowly to the left. The fish started, then with a smooth sweep of its tail lunged for the surface. The big mouth opened and in went the beetle. The rod snapped back, almost reflexively.

In moments a day of frustration and futility had become a stunning success. The fight was brief but fiery, the thrashing fish was soon in hand and quickly back in its underwater lair.

There were times in the long dry spell that preceded that catch when I imagined fish turning around as they fled my clumsy casts and sticking out their nonexist tongues at me.

You begin to think these cold-blooded creatures are laughing at you.

But the last laugh is always best.