Four teacup-shaped bells hang from the top of Omar Sillah's windshield. With a quick jerk of a rope that runs through a small hole in the window, he sends their thin jingle trickling through a dusty community of garden apartments in Laurel.

Within seconds the children appear, shouting, waving, their bare legs flashing between the parked cars and trees as they race for the street.

"The ice-cream man!"

"Hey, Omar!"

The Good Humor man remains an emblem of summer life, despite the vast and still-growing array of ice-cream products in the freezer section of the local supermarket. No store is as convenient as the truck that brings the ice cream to your door, especially when you're too young to drive to the supermarket to satisfy your craving.

The Washington area, in fact, has the largest Good Humor fleet -- 150 trucks -- of any metropolitan area in the country, according to company officials. Mitchell Berliner, the Hyattsville-based distributor of Good Humor ice cream for the region, thinks that's because the tradition is so entrenched here. Good Humor trucks have been in Washington for 70 years.

But although the ice cream and the truck haven't changed much, the Good Humor man has. Almost all the Washington area drivers are immigrants, according to Berliner. The vendors are independent contractors, and word has spread among recently arrived immigrants that the jobs are a good first step up the economic ladder.

Sillah, 29, who is married and has a daughter, came to the United States 10 years ago from the small West African nation of Gambia. He bought his Good Humor truck, a 1979 Chevy, for $10,000 in 1989. Since then he has had the same territory -- a two-square-mile area of Laurel known as Montpelier, just north of the National Agriculture Research Center.

He drives the truck from noon to 10 p.m., seven days a week, from April through September. (During the rest of the year, he has a job delivering new-home guides.) On a typical day he will log 50 miles driving his route, traveling the same streets several times. He won't say how much he makes; according to Berliner, the vendors make up to $20,000 in a season.

The work is tiring, Sillah says, but he likes the way his job has made him part of the community. He knows the names of almost all his customers, and sometimes they talk to him about their problems.

"Over the years, you build up a relationship with the kids," Sillah says. "They know you. They have a lot of things to tell you. Even if you are in traffic, they shout your name. They be on the school bus and they be all cheering, Omar! Omar!' Like that, you know? That keeps you going."

Like the other 149 Good Humor vendors, Sillah starts his workday at Berliner Enterprises in Hyattsville, restocking his truck's freezers with ice-cream bars and popsicles. He also sells soda, candy, chips and spicy sausages.

On this particular day, he is worried about the weather -- hot and muggy, with a chance of a thunderstorm. The hotter the better, you might think. But Sillah says people will stay inside if it's too hot, and many of them won't hear his bells over the sound of the air conditioning. As for the rain, a little would be fine; for some reason, people like to come out and buy ice cream after a light sprinkle, he has noticed. But a heavy rain would mean giving up for the day.

One of his first stops is the Crestleigh Apartments, where he's greeted by a dozen children and a few adults. He knows their preferences, sometimes better than they do.

"How come you didn't ask for a hot sausage today?" he gently ribs one child who has just ordered two popsicles -- a Screwball and a Tornado Rainbow -- and sunflower seeds. She checks her change and then orders the sausage.

He chats with the children, but not for too long. The key to success in the Good Humor business, Sillah says, is reliability -- being at the same place at the same time every day so customers learn to expect you. "The loyal customers, they wait for you. They come to you," he shouts over the truck's roar.

Another rule of Sillah's is to spend most of the day at apartment complexes like Crestleigh. He used to target the more affluent neighborhoods of single-family homes along his route, but he discovered that too many of those children were in day care or at summer camp.

At 4 p.m., he is driving through an apartment community on Briarwood Drive, sees a group of teenagers leaning against a parked sedan and asks about one of his regulars, a 19-year-old. The youth soon emerges from the car.

"How come you don't work, boy?" Sillah asks him. The teenager just grins and puts his arm around a girl buying one of Sillah's hot sausages. "You like my new girlfriend?" he says.

Sillah tells the girl that the youth used to ride around in his truck when he was small. He finally says softly to the teenager, "You watch out."

"That's the sad part," Sillah says as he drives off. "You see kids grow up, and you see the unlucky ones."

He has ambitions for the children he sees along his route. "The kids tell me, I want to be an ice-cream man when I grow up.' And I say, You sure? You can do better than that.' "

Sillah, who is Muslim, stops to pray at 5 p.m. after parking at the side of a quiet road, carefully brushing off the green carpet in the truck before laying his prayer shawl down in the cramped space.

He grabs dinner at a Taco Bell on Route 197 and heads back to work, taking bites of the food in between stops. At 7 p.m., the rain finally comes -- a soft evening drizzle. Sillah heads for the cul-de-sac on Brookmill Court. It's the only stop he makes in that corner of his territory, but it's a good one. There are lots of kids on this block, and they like to buy ice cream right after dinner.

Jackie Chambers and her roommate, Sharon Gilbert, tumble out of one of the houses with their children -- Chambers has a young daughter and Gilbert an 8-year-son.

Chambers says she often doesn't hear Sillah's bells, but the children always do. It seems to be one of those special gifts that disappear during adulthood. "Don't you remember when you were a kid?" Chambers says. "You heard them from a mile away."

At one of his last stops, a 16-year-old girl pours out her woes as she licks a Double Fudge bar. Her sister is mad at her, she tells Sillah, because "she thinks I like her boyfriend." He listens, nodding sympathetically as he handles other customers. "Like it or not," he says as the truck pulls away, "they're going to tell you stories about their personal life . . . You just try to give them the best advice you can."

At 10 p.m., Sillah flicks off the lights illuminating the truck's interior. The bells jingle softly as he speeds through the darkened streets, barely glancing at the gas stations, the liquor stores, the Elks lodge, the thrift stores and the illuminated baseball fields.

It wasn't a great day for sales, he says. Given what he spent on gas, he probably only broke even. But tomorrow will come very soon. CAPTION: Darren Speight, 10, runs as he yells for the Good Humor ice-cream truck to stop as it is leaving his apartment complex in Laurel. It stopped. CAPTION: Omar Sillah, a Good Humor ice-cream truck driver for the last 10 years, waves goodbye to a customer. CAPTION: David Nostro, 13, left, Brian Garrett, 12, and Sara Childs, 13, crowd around Sillah's ice-cream truck to get a cool treat while at the Montpelier Swim and Racquet Club. CAPTION: A group of children in Laurel wave down the neighborhood's Good Humor man, Omar Sillah, who is driving his 1979 Chevrolet ice-cream truck. CAPTION: Omar Sillah, a Muslim, takes time out from his shift to pray. Sillah drives the ice-cream truck from noon to 10 p.m. seven days a week from April through September, logging about 50 miles a day. CAPTION: Anthony Todd Jr., 10, peers into Sillah's truck after it stops at his home in Laurel.