Relaxing in the club car as a train speeds cross country -- that for me is still the essence of adventure in travel. The palpable sense of rolling power that only a giant locomotive generates, the gentle rocking of the car as the changing panorama flips by the window, the look of people embarking on a journey that could change their lives -- the combination excites me today as it did when I was a child.

This feeling of adventure is what led me to take the train from New York to Miami toward the end of last summer.

Even in 1985, leaving from New York's Penn Station offers a sense of serious travel. Old Penn Station, of course, was "classic railroad," its concourse covered with acres of glass domes, arches and huge vaults, the delicate web of steel ribbing cast in shafts of light from above. They ripped all that down in 1965, replacing the upper space with the new Madison Square Garden, the vast house for basketball games, conventions and bowling. The new station, relegated to the basement, resembles a bus terminal.

Still, as we sat there, anticipating the morning train to Miami, the central waiting room gyrated with images of another age: bustling porters pushing stacks of baggage, the destination board flipping rapidly to announce the progression of departing trains, and, up near the ceiling, the man in the glass box ending each final call with a dramatic "Aaall a-board!"

That's railroad.

Even the longest eastern routes -- only the Crescent, connecting New York and New Orleans, covers more miles than the twice-daily, 25 1/2-hour New York to Miami runs -- are equipped with Amtrak's older cars, their stainless steel and glass, their unpainted brushed aluminum reminiscent of that industrial art deco look symbolizing the glory of railroading.

West of Chicago, long-distance trains are what Amtrak calls Superliner Service, which means big, double-decked cars: the Desert Wind from Chicago to Los Angeles, the Pioneer from Chicago to Seattle and a handful more. The newest equipment in the system is used on those lines. First-class bedrooms have showers as well as toilets; observation cars are domed.

They also have the look of plastic and nylon in bright reds and blues, and the feel of metals composed of alloys new and, inexplicably, slightly untrustworthy. Word of upcoming stops and the call to meals crackle from hidden speakers, airplane style.

But our car -- Number 8100 on the Silver Star -- was built in 1949, then refurbished in 1981. Our bedroom, in true railroad tradition, was the model of functional simplicity. Two well-stuffed chairs collapsed at night to make room for a lower bunk flipping out of the wall and an upper bunk dropping from the ceiling. The toilet, contained in its own cubicle, had a metal sink that folded into the wall when not in use.

All the room's features, including the place to put shoes for overnight shining, were described by our porter, who greeted us on the platform and carried our bags aboard, then returned later with baskets of fruit, cheese and mini-bottles of wine.

The train rolled out of Penn Station promptly at 11:05 a.m. Fifteen minutes later we were through the tunnel and in Newark; by noon we were past Trenton and on our way south.

Lunch time ignited memories of the golden era of dining cars, memories long since dampened by an Amtrak attitude toward meals that is inconsistent at best. Acceptable can become inedible in the changing of a semaphore.

Anticipating -- at best -- a limited and uninspired menu, we had packed a picnic lunch.

What a delight. Corned-beef sandwiches on pumpernickle, fresh fruit, cheese and crackers from the complimentary basket, accompanied by a Moulin-a-Vent and topped off with bakery shop cookies, all were enjoyed with our shoes off while zipping through New Jersey and Pennsylvania at speeds approaching 100 miles an hour.

It was not only hills and valleys that entertained us, but fragments of real life, glimpses into a plot begun five miles before and continuing somewhere down the line. Quality voyeurism is a special attraction of the train's route.

Except for devotees of back roads, the long-distance motorist is bored by the monotony of the interstate highway system, a landscape of well-manicured hedges and neat little signs proclaiming the coming of the next McDonald's. He may cross a river now and then, and, in the South, enjoy the sight of an occasional hawk circling over salt-grass marshes, but pleasant diversions are few.

But the train . . . the train serves up endless snippets of backyard America. Through industrial areas, graceful smokestacks rise from shells of silent factories; by farms, little boys and girls in overalls stand to wave as the engineer blows the whistle; and in a hundred small towns, lines of traffic are frozen by the passing streamliner.

Pay close attention -- a nation's past is rushing by that window. Studebakers and DeSotos still run; building walls still praise Crosley radios, Burger beer, grape Nehi and Robert Hall clothes.

The strip from Washington to New York is part of the Northeast Corridor, which sees half the train traffic in the country. Most of it -- from D.C. to New Haven -- is electrified, the cheapest and cleanest source of rail power. But to continue south of Washington the train must stop at Union Station and exchange its electric engine for a diesel. The switch takes about a half-hour and is well worth watching; the sheer mass of a modern locomotive is difficult to conjure from imagination.

Below Washington, the terrain changes. It flattens out, becomes less industrial and more rural. As the tracks cross the Potomac and the Rappahannock, the York and the James, continue past lush tidewater regions, then climb through the foothills of the Piedmont, a history lesson is sung by the clickety-clickety-clickety. Washington, Fredricksburg and Richmond were made safe from Indian and British attack by the rapids of three of the four rivers; the Chesapeake Bay prospers from contributions of all four.

Enjoying the changes in landscape is aided immensely by a good map of the Southeast. Used with the Amtrak timetable, the map is a guide to what is happening on both sides of the track. It alerted us midway through the day and sent us out of our compartment to enjoy the early traces of the Chesapeake out the left side of the car -- the long stretches of marsh grass, the elegant heron and willet, the watermen returning from a morning's work.

The late-afternoon hours -- after resting from lunch and before dinner -- are a good time for touring. As wonderful as the privacy of a compartment is, it is a shame to miss the life that thrives on an overnight train.

Riders seek their own economic level. The more affluent -- and usually older -- passengers occupy the bedrooms or smaller roomettes, or the even smaller single and double slumber coaches. Younger riders, singles and those who cannot afford the $49.50 minimum for some kind of bed sit up in coaches.

Walking down the corridor of the sleeping cars, there is a quiet sameness as door after door, curtain after curtain is pulled shut, except for the periodic claustrophobic and odd exhibitionist.

In contrast, coaches are a hodgepodge. Passengers are black and white, Hispanic and Oriental. Children are everywhere, playing and sleeping and listening to their mothers read stories. If there is any pattern, it is that men travel alone and women travel with kids.

And there are lots and lots of young people -- especially in the summer -- alone, in pairs and large groups, many equipped with big radios and tiny cassette players, almost all, mercifully, with headphones.

By the time we roared through Virginia and the sun began to set, the train was practically full. Every manner of sleeping accommodation was taken, a condition approached on most long-distance trains last summer. According to Amtrak, the Silver Star and Silver Meteor -- the afternoon train to Miami -- showed ridership increases of 40.9 percent over August 1984; overnight trains throughout the country were up 18.3 percent during that month of peak travel.

Amtrak feels the increase was due to the discount fares -- our bedroom, including all meals for both of us, was $337, which compared at that time with all but the most inconveniently scheduled flights; special round-trip fares within the Eastern Region begin at $150 without sleeping accommodations -- and the summer-long debate in Congress on the future of passenger service. (Now, the total fare for two people in a bedroom is $500 one-way. The lowest one-way daytime air fare between New York and Miami is now $129 per person.)

I prefer to lay the surge of enthusiasm to a subliminal understanding among Americans that the train offers something usually available only to the rich -- a civilized way to travel.

Except for those flying first class, or being driven in a stretch limousine, traveling between cities is mostly to be suffered, strapped into narrow airplane seats, or driving, fighting to remain alert enough to keep on the road and spot highway patrol cars in case the speedometer creeps above 55 miles an hour.

The train offers transportation and, simultaneously, a continuation in the normal process of living. Not only is a chosen destination achieved, along the way one can eat and drink without concern for safety, hole up in isolation with a book, pursue marathon conversations, flirt or simply stare out the window and contemplate the meaning of existence.

The experience is not so different from crossing the ocean by luxury liner, a practice nearly abandoned in this hurry-up world. The trip is part of the vacation, to be enjoyed instead of tolerated.

At one time, dining was a major part of that vacation. On an earlier trip south -- in 1947 my family went from Cincinnati to Washington and then south, through Jacksonville to Miami -- I remember linen cloths, shiny tableware and fresh roses, huge roasts carved before our eyes and soup ladled from glistening tureens.

But those trappings of elegance have moved into history, along with the great trains of the time -- the Super Chief, the 20th Century Limited, the Broadway Limited.

There on the Silver Star we were left with cafeteria service. At dinner my chicken was dry, my wife's lasagna painfully overcooked. But the salad was acceptable, the pie served with Haagen-Dazs ice cream, and nobody blinked at my own bottle of wine on the table.

And there was still that extraordinary time, when the meal was over and we were left with the last of the wine, to sit and visit with fellow passengers as the train raced through the night.

It is perhaps at night when I most appreciate traveling by train. Night is when motorists look for a Holiday Inn with space, to set their alarms for 6 a.m. in order to get an early start on the day's driving.

Instead, we returned to our compartment to find the beds made with fresh, cool sheets and fat pillows. Our porter promised that even with a 9:30 call we could still catch breakfast.

Lying there with the lights out, the rubber blades of the little fan whirring in harmony with the rhythmic sound of steel wheels against steel rails, it could have again been 1947. I could no more resist raising the blind on this trip than I could then, to peer out and watch the southland glide by, street lights of tiny towns wearing halos in a window coated with diesel smoke, swamp-like settings made even more eerie by moonglow.

They are enchanting scenes, and timeless.

The next morning we woke to the sight of vast forests of pine trees, so abundant in central Florida. Most are to be harvested for paper mills in South Carolina, Georgia and elsewhere in Dixie.

We ate a breakfast of eggs, biscuits and sausages as the train pressed on, past children fishing with bamboo poles, dogs racing the locomotive, and, at Sebring's little pastel-pink station, a redcap pulling an old wood-plank luggage carrier, its spoked iron wheels unaided by rubber.

That Sebring station was somehow to lodge in my mind. Even on the trip back north, as we drove through the Carolinas and Georgia, reading billboards advertising Crazy Jack's Fireworks, Stuckey's pecan log rolls and the mile-by-mile reports of the approaching South of the Border truck-stop resort, the picture of that stucco station remained sharp. That station, that vintage luggage carrier.

The traffic on I-95 attested to the popularity of the interstate highway system; my wife seems more fond of airplanes now than ever. But not I.

Give me an extra day or two, a good bottle of wine, a book to read and a long-distance train.