An article Monday about commuters should have said that the U.S. Census Bureau had reported that 63,340 Baltimore metropolitan area residents commute to jobs in the Washington metropolitan area each weekday.

Douglas Tweedy's life is balanced between two worlds that are 40 miles apart and are connected by a stretch of train tracks.

The 32-year-old Baltimore resident, a security guard at the Smithsonian Institution, wakes up at 5 a.m. on weekdays, leaves the house by 6:15 and catches a 6:52 a.m. commuter train that gets him to Washington's Union Station in about 50 minutes. It's time enough, he said, for him to stroll to his job in downtown D.C. and punch the clock half an hour early.

"Until last year, I hadn't even thought of working in Washington. D.C. means nothing to me except that that's where my job is," said Tweedy, who had been out of work for about a year before finding an $11,000-a-year job at the Smithsonian's Hirshhorn Museum and Sculpture Garden, located at Independence Avenue and Seventh Street SW.

Tweedy's routine is similar to thousands of other Baltimore residents who have started working in the Washington area in the past decade. According to the U.S. Census Bureau, 63,340 Baltimore residents commute from Maryland's largest city to the nation's capital each weekday. In 1970, 24,731 made the daily round-trip journey.

According to the Census Bureau's Journey to Work and Migrations Statistics Branch, 4.2 percent of all jobs in the Washington Metropolitan area are held by people who live in Baltimore. In 1970, the number of Baltimore residents with jobs here represented 2.2 percent of the District-area work force.

Most of the 25 Baltimore-to-Washington commuters interviewed said that they work in the District because they cannot find desirable work in Baltimore. They explained that they are reluctant to move to the District because of higher housing costs in this area.

Others said that they are "rooted" in Baltimore by family and social ties and are still trying to find work in Baltimore to avoid a journey that totals about 300 miles each week.

A fraction of the commuters, about 5,000, ride the trains to work. Many of those who do said that they consider the train the best way to travel from city to city because of the economical commuter fares offered by Amtrak and the Baltimore & Ohio Railroad.

As part of a commuter program subsidized by the Maryland Department of Transportation, both train companies offer monthly, round-trip commuter train tickets from Baltimore to Washington that cost about $100.

Charles Smith, the department's railroad administrator, said that the agency paid $2,579,000 to run the program last year and reported a revenue of $1,200,000 in ticket sales, meaning the state's subsidy for the service was $1,379,000.

On most trips, the commuter trains consist of four silver-colored coaches. Some trains have diesel-powered coaches that operate without a locomotive. Others are attached to a catenary, an electrically powered wire, much like the old trolley cars. The trains stop at as many as eight stations on the way to and from Washington.

The majority of Baltimore's train commuters use Amtrak, also called the AMDOT (Amtrak Maryland Department of Transportation) commuter rail service, Smith said. Each weekday morning, AMDOT trains leave Penn Station in downtown Baltimore at 6:15, 6:52, 7:15 and 8:23. On their return trips in the evenings, the four trains leave Union Station at 4:33, 5:10 and 5:40 and 6:33. The trip takes 54 minutes each way, according to AMDOT's train schedule.

Leaving Camden station near the Baltimore Inner Harbor, the B&O train has a more southwestern route to the District and picks up a number of Prince George's County residents. There are 89 seats on each B&O commuter coach.

Stations along the AMDOT line include Baltimore-Washington International Airport, Odenton, Bowie and Capital Beltway. Each AMDOT coach seats 117 people and provides no overhead baggage rack and minimum space below the seats.

For Drusilla Perkins, 25, riding the commuter train is a way to bypass the hectic rush-hour confusion.

"It's always fun, once you get into D.C., to see all the cars stuck in traffic on New York Avenue and you're zipping by," said Perkins, an employe at a D.C.-based consumer energy group who has been commuting by train for a year.

But delays on the train are not uncommon, Perkins and several other passengers said. Last March, a pigeon flew into an electrical component on an AMDOT train and short-circuited several wires, causing a four-hour delay.

"I was very pregnant at the time. The only thing that saved the day was that everybody was in high spirits," Perkins said. "People told hysterical jokes, exchanged reading material, walked around and introduced themselves.

"A doctor was on board. Someone told me, 'Don't worry. If we're here two months from now, she'll deliver the baby.' One person was upset--a woman who had left an hour and a half early to catch a flight out of BWI. She missed her plane."

As soon as they board a train, many commuters go off into groups that have met in one particular spot every day for years. Others, like Patti Casella, chat quietly with a friend.

"You either read something or talk to someone or daydream," said the 24-year-old secretary. "Some people sleep. There's not much to do on these trains. The scenery is not very attractive. We might as well be riding through a tunnel."

Things perk up at the end of the week as friends get together for a little boozing and mingling, said Casella, who lives in Odenton, a suburb of Baltimore.

"A lot of people have parties on the train going home on Fridays," she said. "It gets pretty crazy."