The way the weather's been only a fool and his dog would go out. Ninety-eight on Saturday, 100 Sunday and the Orioles on television both days, from Minnesota, no less.

It took every ounce of will power to drag myself from the air conditioner and the birds-in-paradise to try a stream no one seems to know much about - and those who do have nothing nice to say.

"The Monocacy?" asked a voice from the Maryland fisheries division. "No, we don't have any information on that stream. From what I've heard it isn't good for much but catfish and carp. Real muddy. I don't know anybody that fishes it."

Even the fellow at the liquor store right on the river bank bad-mouthed it. "Oh, I see kids go down there, but they don't do much."

The Monocacy, which flows from the Pennsylvania border south past Frederick and on to its juncture with the Potomac, is getting a bum rap.

A colleague and I settled that for ourselves on Saturday, when we journeyed to the Rte. 355 bridge an hour from Washington. We had only the afternoon to spend so we didn't bring boat or canoe. We had to leave early so we knew we'd be fishing the hottest and least productive part of the day. We weren't expecting much.

But we had a fine time, cooled ourselves in the fast, waist-deep water, caught enough smallmouth and large-mouth bass to keep it interesting and took home enough delicious, handsized sunfish to make it worthwhile. For a capper, we watched a local pull a handsome two-pound smalmouth out on his first cast.

"It can be a fabulous river," said Dr. Jim Gilford, chairman of the biology departmnent at Hood College and an avid Monocacy angler.

"But it's got some problems," he added. "There's a fantastic load of silt that comes down from Double Pipe Creek up north, and even in the summertime the river runs muddly more often than it runs clean. It's a real shame, because thesilt could be controlled.

The real problem comes in spring, Giford said, when the bass move up on the beds to spawn. "The filds are freshly plowed. When it rains hard te river runs red, the beds get silted in and we lose the year's spawn."

once every four of five years the weather lends a hand. Spring rains are light, the bass spawn successfully and the Monocacy is a fisherman's paradise.

"I remember one April several years ago when (outdoor writer Lefty Krch and I floated the Monocacy. We picked up over 100 fish in a day, and we threw back several in the three-and four-pound class," Gilford said.

One thing's for sure: the Monocacy is fertile water.

Once while I was casting in knee-deep water I was pestered by taps at my legs. I looked down to see swarms of minnows pecking at me while I cast to their mortal enemies.

There are crayfish, too, and stoneflies, mayflies, hellgramites, dragonflies and a variety of other small stuff for the game fish to feed on.

Gilford recommends the upper stretches for the best smallmouth fishing. "Take Rte. 15 north from Frederick," he said "just about anywhere north of Frederick you can take a side road off to the east and cross the Monocacy. It's all good fishing up there. And south of Frederick is the better largemouth fishing because the river is wider, shallower and slower.

Gilford was shocked at our choice - the Rte. 355 crossing.

"That's right below the Frederick sewage plant," he said disapprovingly.Nonetheless, we found the water inoffensive and the fishing respectable.

Another plus for the Monocacy is that it's a fine canoeing river, and right now the level is high enough to avoid arduous portages.

There are some deep holes, which is where the fish ought to be, but Gilford isn't giving everything away for nothing. He kept their location to himself, but they shouldn't be hard to find with a canoe.

One insight: The Monocacy has stretches of shallow, slow water over sandy bottom that are just plain unproductive. Look for fast water, riffles, current or rocky bottom.

"That's just stuff any good fishermen would know automatically," said Gilford.

Like me, I skipped over just such a shallow, sandy spot. Then along came that local guy, Mike Quick, who threw spinner bait over the sand and latched onto that two pound small mouth.

Theories are great, but don't bet the rent on them.