IT IS DAWN, after our first night of cross-country travel. My 9-year-old daughter Nicole and I are riding Amtrak to Spokane, Wash., to visit my sister and her family, with a stopoff in Minnesota. I have 10 days of vacation, our tickets and a few discretionary dollars.

As the pale morning lights Fort Wayne, Ind., I also have the wisdom of hindsight. At mignight, we squirmed into position in our coach seats, shivering under the relentless air conditioning. My cotton blazer and Nicole's windbreaker were little comfort. c

Bleary-eyed, I wash up and we breakfast in the snack bar, greeting our companions from the previous evening, a nurse and a teacher. The night's conversation was fine but I wish I has accompanied it with something alcoholic rather than cup after cup of stimulating coffee.

From LaCrosse, Wis., to Winona, Minne., we admire the wide Mississippi, mile after mile of placid blue only rarely ruffled by a pleasure boat. It's a foretaste of the contrast that will impress us between the heavy traffic and snug but people-scarred countryside of the East Coast and the wide open, sparsely populated Midwest and West.

Cousin Lenor Scheffler meets us at the depot and we drive to her house on the Lower Sioux Indian Reservation near Morton, Minn. (pop. 591), my childhood home. We first met Lenor when she came to Washington to work for a congressman. The contact awakened my curiosity about the scenes of the unhappy childhood I had resolutely left behind 30 years earlier, but I don't plan to look anybody up. Just look around. Sunday

Lenor shows us St. Cornelius, the tiny mission church, and the boarded building where she attended elementary school. I never had before visited the reservation. "But you'll come back," Lenor says, "because when I marry it will be in this church." "Don't marry too soon," E warn her, "because it takes me a year to save up for another trip."

We cross the Minnesota River into town. My sister and I used to fish for bullheads here, skipping from rock to rock on its hilly banks. The Morton drygoods store is gone, and so is the corner soda fountain where the high school gang hung out, watching the buses arrive and depart for the Twin Cities. Behind the football field is a new tennis court, but the doctor's house still marks the edge of town. The doctor himself is in his garden, weeding. His son, my classmate, has gone elsewhere to practice.

I must be in a time warp. They've moved the one-room school I attended and made a museum of it. The Methodist church is lockes do I can't visit the basement where I served tables for Ladies Aid socials. The minister no longer lives in the parsonage, but comes for the service only.

We drive toward "our" farm, through a countryside green and yellow with tall corn, soybeans and, surprisingly, sunflowers. We pass Birch Coulee Park where we held our annual school picnics and trembled when our final report cards were passed out. Bloody deeds took place here during the Sioux uprising in 1862.

We reach the corner where our mailbox once stood, shaded by a tree, a half mile from the farm. No trace of either. Although nature is dismaying mutable in Minnesota, it is in no danger of being overwhelmed. Instead, you have to keep hacking to keep the green at bay.

The farm is barely recognizable. The house has been expanded and the windbreak grove is tamed. The decrepit outbuildings, hog and cattle pens, car shed, corncrib, haystack, garden, windmill, even the tree where the tire swing hung, are gone. Neat fir trees have replaced the undisciplined masses of lilac, rose bushes, grape vines, and flowering cloves. Grass covers the workaday yard where chickens used to scratch and spring rain made pockmarks in the dust.

My oldest sister and her husband arrive from Lost Angeles to meet us. She is my link with that past and I accompany her on visits. Various families of kin gather at the house of another cousin. Her husband works for the state and she makes a double career of farming 360 acres and painting rural scenes. Our parents were estranged in the hardscrabble days when first-generation farmers grasped for land, and my mother, a widow, was squeezed out. Although that feud altered the destinies of us children, it's not of our generation. All the farms look prosperous now, and all the people mellow. Monday

We visit the family cemetery, as flat and treeless as the surrounding croplands. I run my hand over the pink granite marker and its cool smooth surface evokes long ago visits to a father I didn't remember.

I treat our group to lunch in Redwood Falls where all the local business is done these days, and then we start on a round of visits over endless cups of coffee. None of the hard stuff in Morton.

We greet a neighbor, Billy, with whom I used to splash in the muddy creek that ran through the pasture. A trim, handsome man in his 40's, he makes me smile by saying, "You haven't changed." In some ways, he hasn't either. At 7, he drove his father's tractor to our farm, and I rode back with him, not sharing his confidence but not daring to let him go alone.

His mother serves us a meal. Our second lunch is delicious; each item utterly familiar from long ago church suppers: pineapple rice, cucumbers in cream sauce, macaroni salad and a luscious homemade blueberry pie. We waddle off to the next visit.

As we rise again to leave, the hostess springs into action, dealing plates. Forgetting etiquette, I plead that I've eaten lunch twice already. "Not here," she says firmly, and proceeds unruffled. The table groans and so do I, inwardly. Anxious not to offend, I praise the farm fresh tomatoes and sneakily forgo the three desserts. Tuesday

Weary, we splurge for a sleeper on the Empire Builder out of the Twin Cities. It is the last compartment of the last car and it swings like the tail of a crack-the-whip line. We sleep blissfully.

I wake among the wheat fields of North Dakota, strewn with bales of hay like huge jellyrolls that signal some evolution in farm machinery since I was a child. Then, a binder threw out sheaves of wheat that we braced upright, teepee fashion, in groups -- shocks -- to keep them dry until threshing time. We children loved that hard work -- even through the stubbles left our ankles bleeding -- because we got to eat the hearty lunches the women packed rather than having to tote them out ourselves to the field hands.

My daughter and I play "fishing," a game whose goal is to hook a new friend with conversation. Now, her first fish, Jennifer, has detrained and Nicole is restless. I cast out bait for her even though she protests. I've already invited a child in overalls with a pretty blonde bob to play cards and soon the two are absorbed.

When it gets too dark to enjoy the distant blue mountains, the firs and craggy slopes of Glacier Park, Nicole and I decide to take a nap until our arrival near midnight. We drift off, assured that we will be awakened before our stop.

Actually, a lurch into movement alerts me that the train is leaving Spokane. I tear, barefoot, through four cars and gasp out my story to an attendent. After a long walkie-talkie exchange, they decide to back up the train and let us off. I pull Nicole, still asleep, from the upper berth and we stumble into the station, leaving angry train attendants berating one another for the delay.

The station personnel are not surprised. My sister, Vivian, had searched every coach, insisting, "Wini is totally reliable." True, but a sound sleeper. Wednesday

After sightseeing in town, my sister arranges a reunion of our side of her big family: grown children and their spouses and towheaded offspring and her own adopted second family, of an age for Nicole to enjoy.

I am happy that Nicole can meet all these kin, most of whom were abstract names on Christmas cards or bodieliess voices on the telephone. Our two-person family will not seem so isolated in Washinton now.

My brother-in-law Ken drives us up to their cabin on the Spokane River, with side excursions along the way to view the imposing wall of Grand Coulee Dam, to descend into icy underground caverns and to follow a waterfall through birch and cottonwoods. The children swim, pulling up rushes from the riverbed as the tame ducks glide over in tight formation. Nicole spurns the warm comfort of our bunk bed to shiver in the loft with her cousins. Viv and I talk until the early morning hours. Thursday

Ken is on friendly terms with this countryside where he grew up, within close driving distance of 50 lakes, and little sawmill towns whose baseball teams met his in sandlots.

Time reels by and I try in vain to find a flight back to Washington. Our train tickets are unaccountably stamped for the previous day: their error or mine? I don't know; maybe time looked longer from a distance. The only available flight is first class and well beyond our means. Nicole cheers at my failure because she loves the train.

At 2:20 a.m., we are on board and, luckily, there are plenty of seats. By now, we have settled into a rhythm and it seems quite natural to be rocking across the continent in a windowed cylinder.

We haven't entered a single store or sent a single postcard or used any clothing but the jeans we washed in Spokane. I almost always underpack but not this time; I should have taken only a backpack and a blanket.

We will arrive late Monday in Washington and I will be at work on Tuesday. If I used too much time getting there and back, it was still full and it gave Nicole a good idea of just how wide, diverse and beautiful her country is. And it gave us time to absorb and relish the roots we explored and the memories we made.