TRAINS AND their haunting whistles come out of nowhere, their destination unimportant, interrupting mundane musings for long, breathless moments. Sadly, a whole generation of kids is growing up never hearing that whistle, because it's drowned out by the Beltway at rush hour. And anyway, they think a "train" is that gleaming silver tube mom or dad leap into at Silver Spring.

Even if you're not a railway enthusiast, you can find some special ways to encourage railroad ties to the past and future -- and at least one of these routes is via Amtrak. The National Railroad Passenger Corporation (that's Amtrak) sponsors a tour program that lets you climb aboard its equipment, hear some wonderful train stories and get the feel of Washington's Union Station -- along with information to teach the kids respect for the tracks. Through the efforts of Amtrak's Arthur Lawson and his "Officer Choo-Choo" puppet, 400,000 schoolchildren around the country got the message last year.

Lawson, an Amtrak police training officer, knows trains -- and kids. "You wanna look at some old trains and then some new trains?" he asks his young visitors at Union Station. "Before we find out what there is to see here, we have one new rule for you to remember always. That rule is simply, 'Stay off the tracks.' When it's a tie, you lose! Don't run, jump, play ball, or walk on the tracks. Can you say it for me?"

"Stay off the tracks!" the kids shout above the din of the main terminal.

The restoration of Union Station is scheduled for completion this fall, at which time the current temporary station will be replaced by tracks and platforms. Admittedly, the present setup doesn't comfortably accommodate the volume of rail passengers coming through D.C. -- there just isn't enough waiting area and things can get crazy. Lawson explains this to the group, and then addresses the question of what any normal kid will do when he sees a crowd this size: get lost and scare the pants off his parents. He pulls nine-year-old Matthew Rose out of the tour group and they both disappear into the Passenger Services office. In a few seconds, Lawson's voice is booming out of the terminal speaker system: "May I have your attention please? Will Elyse please meet Matthew in the Passenger Services department?"

Nine-year-old Elyse Beaulieu blushes; Mathew emerges looking grateful for this providential chance to embarrass a girl. "Now you know what to do if you get lost," says Lawson. "Does everyone have their driver's license this morning?"

"We're under the age limit," points out eight-year-old Katie Beaulieu.

"Oh well, let's have some fun anyway," says Lawson. He guides our group outdoors to the trackside area and directs all eyes to the tall switching tower nearby. "The people up there control all the trains between Landover, Maryland and Virginia Avenue, just on the other side of the U.S. Capitol. From the tower, the switcher sometimes can't see those trains coming up from the south. But there are computer screens in there with rows of blinking lights to show the movement of each train at any moment."

Lawson holds up a chunk of rail 36 inches long and a few inches wide. "This is an actual switch," he explains, pointing out the detector on top that signals the tower when a train has passed over. The officer describes the placement of the switches along the train tracks: a quarter-mile apart on the mainline and 100 yards apart in the station. "If we want to run a train to a different track, we can push some buttons in the tower and move the switch to help change the track that the train is going on."

To keep little fingers off the switches on the rails, Lawson has a convincing demonstration. He places a whole melon (in season, we presume) in the jaws of the device, then throws the switch, demolishing the melon. "Kids can throw a switch . . . throw your trains," he adds as an aside.

Within the next several years, a computerized operations center in Philadelphia will control switching for the entire corridor from D.C. to New York, eliminating the need for manned switching towers along the route, according to Amtrak's Clifford Black. "The center looks just like the Starship Enterprise, or the screen from the movie 'War Games,' " says Lawson. He goes on to describe tiers of seats before a wraparound screen, from which operators will control all the movement of the trains in their area.

At another area of the train yard, small diesel cars are moving coaches around to create a new train set, or "consist." There are other treats in store; we step up and amble through a club car, a coach car, and the President's Car, a special charter coach called the "Quarter Clipper" (queen-size beds, formal dining room, stereo system and VCR; you get the picture). We inspect refurbished sleeper cars, built in 1945 and still in use. Finally, Lawson hoists us into the black swivel chairs of an Amtrak AEM-7 electric locomotive. We pat the red brake, finger the speed throttle, gaze silently at the simple control panel. We can almost feel the rhythm of the rails.

As the Smithsonian's curator of Transportation, Bill Withuhn understands our family's delight in a pilgrimage to the National Museum of American History's Railroad Hall, where the venerable Southern Railway Steam Locomotive No. 1401 stands by a window. Forever stilled in its tracks, perhaps. Yet it continues to streak recklessly across the landscape of the imagination.

"Amtrak president Graham Claytor ribs us constantly that this lovely engine, which he regards as a preeminent national symbol, is trapped inside the Smithsonian," says Withuhn. "My rejoinder is that, as former head of Southern Railway, Mr. Claytor should have saved two of them.

"It never was first or biggest or most powerful, but I don't think the Smithsonian could possibly have done better."

Probably not. This same steam engine was in heavy service in the 1920s along the Southern Railway, including Asheville, North Carolina, the hometown of Thomas Wolfe. One can imagine Wolfe stringing together his elegant, painful sentences on sultry southern nights to the sound of old No. 1401 barreling through town: "Thunder of the great flanged wheels/The long retreating whistle wail."

ALL ABOARD!

The following is a sample of rail-related ideas and outings as suggested by Bruce Heard, Amtrak's resident railroad enthusiast, and Bob Snyder of the National Railway Historical Society.

AMTRAK'S UNION STATION TOURS --

Call Officer Arthur Lawson in Baltimore at 301/291-4230 8 to 4 weekdays (Wednesdays, in D.C.: 289-2390) to schedule a station tour or to invite Amtrak's "Officer Choo-Choo" puppet show to your school or organization.

SMITHSONIAN RAILROAD HALL

in the National Museum of American History, Constitution Avenue between 12th and 14th streets NW, open 10 to 5:30 daily. 357-1300.

B&O RAILROAD MUSEUM --

Four blocks west of the Inner Harbor in Baltimore, open Wednesday through Sunday 10 to 4. 301/237-2387. "One of the best museums in the U.S. for restored vintage locomotives and passenger cars. It's in a very fine roundhouse from the days of steam locomotives," says Heard. "I would rate this as a four-star exhibit. It's old. Nothing phony about it, it's all real."

NORFOLK-SOUTHERN RAILWAY HISTORIC STEAM EXCURSIONS --

May 14, 15, 21 and 22. Vintage steam locomotives and coaches are fired up for daytrips originating in Alexandria with tentative destinations of Lynchburg, Front Royal and Charlottesville, Virginia. Each destination includes a three-hour layover with the offer of a sidetrip, tour or something interesting. Choice of coach and first class, fares begin at about $40 for adults, slightly less for kids. Call or write Potomac Chapter, National Railway Historical Society, Box 235, Kensington, MD 20895. 946-9461.

RAILROAD ENTHUSIASTS, CHESAPEAKE DIVISION --

Call Phil Bush for information about excursions, talks and other club activities. 544-3399.

RAILROAD MEMORABILIA CONVENTION --

One major train show occurs annually in this area every fall; call Charlie Miller for details, 536-2954.

NATIONAL RAILWAY HISTORICAL SOCIETY --

Potomac Chapter meets monthly at Montgomery County Library's Kensington branch, all meetings at 8 p.m. on these dates: February 10, March 23, April 13, May 11 and June 8. Dues $14 a year. There are still some all-color railroad calendars available through this chapter, $6.50 postpaid; call 946-9461. For information on the D.C. Chapter, write to NRHS, Box 487, Washington, DC 20044. Area chapters sponsor summer family picnics, private steam excursions, other events.