FRANKLY, WE NEVER had time to barbecue on the Fourth of July. It was a full enough day playing patriot--those were proud, flag-waving years--and parading through our town in the social highlight of the summer.

Photographs with curled edges show a serious and slightly frightened Miss Liberty, not yet old enough for school, being pulled in a wagon by a brother, two years older, dressed as Uncle Sam, the sweat collecting in his puffy cotton beard. The parade was followed by a decorated bicycle contest, for which we had spent hours weaving streamers through the spokes of our balloon-tire two-wheelers, and more hours winding crepe paper around every bar so that our hands and legs were stained red, white and blue for the rest of the day.

Breakfast was ice cream along the parade route, even in later years when we merely watched our younger sisters strut and twirl batons while we lounged teen-cool on the curb. If we ever ate lunch we were too excited and busy to remember it, for there were carnival rides and three-legged races and secret rendezvous for lighting bootlegged firecrackers. We must have had dinner; our mother would never have let us get away without some early evening protein and greenery (though my father still boasts the only green vegetable he ever ate was a dill pickle) before the fireworks.

Even with all the excitement of races and contests and parades without intermission, we reserved a surge of thrill for the fireworks. The best day of the year it might have been, yet we couldn't wait for dark. Blankets stretched on the stubbly grass overlooking the lake, lying on our backs watching the sky darken, we had our first quiet moment.

And then we smelled everyone else's barbecues. The sharp tang of singed hotdog casings. The familiar and delicious meatiness of sizzling hamburgers. Sausages pungent enough to eclipse all other hibachis. The few adventurers doing shish kebabs, sending heavy lamb fat aromas our way.

I have always and ever since loved other people's barbecues.

Like every red-blooded American cook I have barbecued all my culinary life, and with sufficient enthusiasm that I have started the season with winter jacket and gloves, running up and down from my second-floor apartment to the back yard with a flashlight to see whether the butterflied lamb was done. I, too, carried a hibachi in the trunk of my car from May to September for improvised picnics, and had the fire department show up when I tried to stretch the season by grilling on the windowsill with a good strong fan.

But that never diverted me from the search for somebody else's best--or at least most outrageous--barbecue.

This year I have added two to my hall of fame.

On Capitol Hill they eat barbecue in suits. I discovered that one beautiful spring evening in May, when the Democratic National Club was having a picnic in that most American of picnic sites, a parking lot. What appeared to be a blackened railroad engine welded to a shiny new trailer stood at one end of the lot, and a line of just-from-the-office revelers stretched across, right up to Rep. Dave Obey's (D-Wis.) bluegrass band.

The barbecue contraption, it turned out, was an old propane tank with a chimney at the pointed end, the end opposite where a fire had been built so that the smoke would travel the whole 18-foot length through the racks of meat before it exited. And the barbecuer, even more suprising, was a man named H. Rainier Thuleweit from Dusseldorf, West Germany. Thuleweit, who also runs the kitchen at Csiko's Hungarian restaurant on Connecticut Avenue plus those at the Westchester Apartments and the DNC, bought the machine four years ago for $2,000 right off a guy from Georgia, who had brought it to town for a barbecue during the Carter administration. All Thuleweit needed then was the trailer--another $2,500--and a few lessons in the unfamiliar art of barbecuing. For those, he watched the original owner, say, 10 or 20 times. And he was in business, cooking for up to 500 people at a time.

For the DNC party he used 550 pounds of meat, half briskets and half boston butts, and started the fire of hickory logs 24 hours before in his back yard in Olney. All night he fed it more hickory logs, then let the fire die down so there would be no flames to transport on the highway at noon when he hitched the giant smoker to his van for its ride to Capitol Hill.

To serve, he props open the doors cut in the side of the gas tank, and in turn they provide an occasional conversation piece when the two-by-fours slip and they clang shut loudly enough to immobilize the party for a moment. He spears slabs of meat from the racks inside to a cutting board on the buffet table flanked by rolls and beans and slaw and sauce. The meat is unseasoned, just charred to a crusty black. It cuts tenderly and juicily into slices rimmed with a half-inch smoke-reddened ring edged in black. Thuleweit doesn't pay much attention to what happens to the meat after that, providing for seasoning nothing more ambitious than Open Pit barbecue sauce livened with bottled hot peppers. But he does grow enthusiastic over the prospect of barbecuing such things as whole turkeys, which he did for the Rayburn Cafeteria a few years back, and marinated whole pigs or Hungarian kettle goulash. He can also build a fire right under the rack for grilling hot dogs and hamburgers. And Thuleweit is probably the only barbecue caterer who advertises that he also will provide hay rides, trampoline, pony rides and "babysitting by request."

As for the second memorable barbecue, the mood was far from down-home. Around Jeremiah Tower's barbecue there is a hushed silence, as if at a shrine. This Berkeley, Calif., chef, formerly of Chez Panisse and now of the Santa Fe Bar & Grill, was feeding food writers at an extravaganza put together by the Ocean Spray cranberry people and titled Innovations '83. This was no ordinary back yard roll-up-your-sleeves lunch, for the back yard was the Astors' Newport, R.I., mansion, Beechwood, where the next-door mansions hid behind high walls so that all one could see was green velvet grass and water.

Buffet-table-long grills--fueled with mesquite, of course, and not briquettes--were building heat. For a perfectionist like Tower you can't start worrying about flavor too early in the game, so he was marinating live crayfish. The tomatillos for the salsa had been hand-chopped. Lobster shells had been chopped and pure'ed in a heavy-duty mixer for hours to prepare the shellfish butter. The whole peppers--in every color known to California--were blanched, oiled, charred, peeled, then grilled again. Lamb loins were marinating in a discreetly commercial mixture of cranberries, thyme, olive oil and pepper. An aquarium's worth of live lobsters, crabs, oysters, clams and skewered shrimp awaited their turn at the grill while the staff, wrapped in long white aprons, grilled coils of sausage for hors d'oeuvres and cut them into bite sizes to dip in the tomatillo sauce. At the last minute one grill was covered with seaweed to steam, sizzle, moisten and flavor the sea creatures laid to rest on it.

This was a white-tablecloth barbecue, with centerpieces of oiled and brilliant-hued vegetables. First came the seafoods, with garlic and smoked chili sauce to slather on, and shellfish butter to dab on. Then the lamb, crusty and permeated with mesquite flavor, with the grilled vegetables glistening with olive oil, and a salad. Next the required course for any innovative 1983 meal, grilled California goat cheese and sun-dried tomatoes, this time the cheese sandwiched between the tomatoes and then wrapped in grape leaves before being grilled. At the end, a warm "ragout" of tropical fruits over ice cream.

Tower is a food photographer's fantasy. He stands tall and regal, cool enough to tame the fire. The vegetables glisten red and purple and soft yellow. He likes to throw fresh herbs on the fire just before removing the meat so that the herb flavor permeates the meat, but even more picturesquely he ties bunches of herbs into a makeshift pastry brush to add their own aroma as he brushes on the marinade with them.

I kept wondering what Tower could do with a hot dog. GRILLED MIXED SHELLFISH WITH GRILLED GARLIC AND SMOKED CHILI SAUCE (6 servings)

Any combination of shellfish can be used, or just shrimp or even scallops. 2 lobsters, each weighing 2 pounds 4 blue crabs 18 prawns or jumbo shrimp, with peel left on 12 oysters, scrubbed 12 little neck clams, scrubbed For the marinade: 10 cloves garlic, chopped 4 serrano chilies, seeded and chopped 2 cups olive oil 1 teaspoon pepper

Place lobsters and crabs into boiling water and cook for 5 minutes. Drain and cool. Separate lobsters into sections--tail, body, claws. Remove shells from crabs leaving body with claws detached. Discard body shells. Place lobster pieces, crab bodies and shrimp into a bowl. Place oysters and clams into a bowl of cold water. Mix remaining ingredients and pour over shellfish in bowl. Marinate in refrigerator for 1 hour. Drain and spear pieces on heatproof skewers. Reserve marinade and place into a small bowl. Place spears of shellfish, oysters and clams (well-drained) on grill 6 to 8 inches above gray coals. Grill until shrimp are cooked and oysters and clams open--or can be opened easily--about 15 to 20 minutes. Place sauce in center of a large platter and surround with shellfish for dipping. GRILLED GARLIC AND SMOKED CHILI SAUCE (Makes about 2 cups)

Can be brushed on meats, poultry, seafood and vegetables just before or after grilling. 5 dried ancho chili pods 2 cups olive oil 5 whole garlic buds, rubbed with olive oil and broiled slowly until soft Grated rind and juice of 2 limes 2 tablespoons chopped fresh oregano Salt

Broil chili pods slowly, holding them with a fork over a hot burner, until they puff. Do not char them. Place pods in water to cover and soak for 2 hours or overnight, weighted down with a plate so they remain immersed. Drain and remove stems and seeds. Pure'e pods with 1 cup of the olive oil in a food processor. Press pure'e through a sieve. Set aside.

Peel off outer layers of garlic buds, remove stems and membranes from individual garlic cloves. Put cloves and remaining olive oil in food processor and pure'e. Press pure'e through a sieve. Discard residue left in sieve. Rinse the food processor and add chili and garlic pure'es. Add lime rind and juice, oregano. Process until soft and smooth. Season to taste with salt. Pack mixture into a crock with a tight-fitting lid and refrigerate until needed. GRILLED CRANBERRY-MARINATED LAMB WITH CRANBERRY CHILI RELISH (6 servings for loin, 12 servings for leg) 1 bone-in loin or butterflied leg of lamb, fat trimmed, about 6 pounds For the marinade: 2 cups fresh cranberries, pure'ed and sieved 4 sprigs (about 1 tablespoon) fresh thyme, stemmed and chopped 1/4 cup olive oil 1/2 teaspoon pepper For the sauce: 2 cups fresh cranberries, chopped* 1 tablespoon chopped peeled fresh ginger 1 serrano chili, seeded and chopped 3 oranges, peeled, sectioned and seeded Grated rind of 2 oranges 1/4 cup olive oil 1 teaspoon salt

Mix marinade ingredients in a bowl. In another bowl, mix all sauce ingredients. Let stand at room temperature for 1 hour to allow flavors to blend. Spread lamb with marinade ingredients and let stand at room temperature for 1 hour. Scrape off marinade and sprinkle lamb on all sides with salt. Place lamb on charcoal grill 6 to 8 inches above gray coals and grill about 15 to 20 minutes on each side or until medium rare and pink. Let rest for 15 minutes, then carve--lengthwise along the bone for the loin. Serve slices topped with cranberry chili sauce. Serve with your favorite grilled vegetables.

*Cranberries are not routinely available at this time of year but some stores, among them Sutton Place Gourmet, have them in the freezer. WARM RAGOUT OF TROPICAL FRUIT AND WHITE WINE (6 to 8 serings)

Use whatever fruits are in season. The principle of cooking this dish is similar to that of cooking a vegetable stew. The longest-cooking fruits are added to the pan first and the most tender fruit is added at the last moment to just warm through. The sauce is reduced, then thickened with butter just before serving. 3 cups semi-dry white wine (riesling, semillon) 18 gooseberries, pink or green 12 strawberries, hulled and halved 2 ripe mangoes, peeled and cut into slices 3 tablespoons unsalted butter 1 pint raspberries Pinch salt 6 to 8 scoops vanilla ice cream

Put wine into a saute' pan and heat until just simmering. Add gooseberries and simmer 1 minute. Add strawberries and simmer 1 minute. Add mangoes and simmer 1 minute. Cook only until tender but not falling apart. Remove fruit carefully with a slotted spoon and keep warm. Bring liquid to a boil and reduce by half. Swirl in the butter. Replace fruit in liquid and add raspberries and salt. Mix gently until just warm. Spoon fruit onto serving plates around a scoop of ice cream. If desired, reduce fruit juices further until slightly thickened. Spoon hot juices over fruit and ice cream.