ALENVILLE, N.Y. — On an early fall evening in 1992, Steve Kluge and a group of high school science students from Bedford, N.Y., were hiking toward a sandstone escarpment called the Pine Orchard high above the Hudson River, and Mr. Kluge was preparing them for what they would find: the past.

Or rather, he said, many pasts all coexisting together — the ancient past of deep time that had shaped the Catskills in an age before dinosaurs, and the more recent past of the last few hundred years. As darkness gathered, he told the students about the landscape artists and tourists who had come here, and the great hotel called the Catskill Mountain House — now only a ghostly presence of etched lines on the stone — that had dominated the cliff 150 years ago.

The experience changed Kristin M. Woodell's life. Sitting there on the rock, staring out into the night, the 17-year-old senior — then Kristin Johannessen — suddenly knew what she wanted to do. She would teach earth science like Mr. Kluge so that she could perhaps reproduce the power of this moment for other young people. She made good on the promise, too. This spring she finished her third year teaching at her old high school, Fox Lane, about 40 miles north of New York City in Westchester County, and has returned every fall at Mr. Kluge's side for the senior science field trip's hallowed night hike to the Mountain House ruins.

"It all stemmed from that trip," she said.

There were many hills and valleys seen in the paintings of the old Hudson River School that people believed could empower or enthrall a soul, but this one — a once-remote Catskills perch 2,200 feet above the river valley — was the unquestioned reigning queen.

It was a place where picturesque scenery became something more — sublime and larger than life and capable of evoking the deepest awe. Many of the paintings that defined the American landscape in the 19th century were produced within a few miles of this spot, and for generations of people in the days before Mickey Mouse and supersaver airfares, that made coming to this table-rock cliff a lifelong dream.

Mr. Kluge, now 49, a bearded, bearish man of rumbling enthusiasm, said he believes the power of the Pine Orchard still exists, and for the last 15 years he has been coming back to tap it. The world, he has told a generation of students at Fox Lane, is a riveting detective story of ice and wind and stone and immeasurable time — and also art and beauty.

He teaches geology in part by going back to places in the Catskills where Hudson River School pictures were painted, and photographing his students standing as though in the frame of the old artwork, beside the same rocks and waterfalls. The evidence of why things are the way they are lies strewn about us, he said, and the great intellectual game of life is to figure out how the pieces once fit together.

"We look out and we imagine the past landscape 600 million years ago and how it's changed since then — this is a good place to do that from," he said, patting the ancient sandstone on a recent visit back to the Mountain House site.

"This stuff that we're sitting on is the erosional remnant of the mountain range that existed across there," he said, gesturing east toward the Hudson Valley. "A vast huge mountain range, snow-covered at the top, and all this stuff is eroded off those mountains and deposited here."

Mr. Kluge paused. He stood and turned west, and with a sweep of his arm, as though he could actually see it, described what lay on the other side of the Catskills in those long-ago days. "This is the delta of a great sea that existed to the west of us," he said. "The shore of a great sea."

The idea that a person could stand here and get a glimpse into some place beyond ordinary time is not new. Natty Bumppo, the leather-stockinged hero of James Fenimore Cooper's novel "The Pioneers" (published in 1823, the same year the Catskill Mountain House opened for business), described the view from the Pine Orchard, and his words ultimately became a 19th-century cliché, repeated in gushing tourist literature and overwrought nature poems for decades afterward.

"What see you when you get there?" Bumppo is asked by another character in the book, after Bumppo has described his hike to the precipice.

"Creation," Bumppo answers simply. "All creation."

Embracing the Sunrise

Every day at the Catskill Mountain House began the same way — with a knock on the door, as employees made the rounds in the pre-dawn darkness to the hotel's hundreds of guest rooms. The sunrise was coming.

"Nothing was more inspiring than the famous sight of `all creation,' under the first break of day," writes Roland Van Zandt in his book "The Catskill Mountain House: Cradle of the Hudson River School" (Black Dome Press). "Half of America must have tried at one time or another to describe the immeasurable view with yards of shimmering adjectives."

"Sunrising," as the act of morning witness came to be called, was a spiritual moment for some people, a tourist memento for others. But historians say that for at least some of the upper-class, educated visitors to the Mountain House, sunrising was also a kind of meditation on the nature of time. And when a young artist named Frederic Edwin Church painted what he saw from the hotel's balcony in 1849, that meditation is what he captured.

Church's picture, called "Above the Clouds at Sunrise," is barely a landscape picture at all in the traditional sense, because the land barely exists. There's a pitch pine to the right, a few rocks to the left, and beyond that, only atmosphere, a free-floating never-to-be-repeated essence of light and morning mist and pure process unfolding.

"It's the dawn of creation — a stirring created by light and heat," said Gerald Carr, a consulting art historian for Berry- Hill Galleries in New York.

Time was a hot topic in Church's day. Louis Agassiz had recently proposed the stunning theory that much of the land was once covered by mountains of ice. Charles Lyell, the English geologist who inspired Charles Darwin with the notion that landscapes had incrementally evolved over millions of years, was lecturing his way across the United States in the 1840's. James Hutton had postulated a theory of deep time that extended back, and into the future, beyond human comprehension.

"It's the 19th century that invented our modern sense of time," said Donald Worster, a professor of American history who specializes in environmental history at the University of Kansas. "The breakthroughs in geology and evolution, in looking at the natural world, were signaling a shift in consciousness — we're still living on the basis of that change."

As Mr. Kluge points out to his students, the Catskills — however glorious — aren't really mountains at all, as people in Church's day believed, but rather giant piles of mud and rock that settled here as the real mountains — the vast Acadian range to the east — eroded away beginning about 380 million years ago. The sandstone of the Pine Orchard is really the old compressed bed of a Devonian Period river that rushed off the Acadian western slope, altering everything in its path.

Teaching and Inspiring

The chain of art and stone and time extends in other directions from this place — notably to the State University of New York at Oneonta.

Out of a typical class of 20 to 25 earth science majors in any given year, at least one or two are from Fox Lane High School, university officials say. Ms. Woodell studied here, and Mr. Kluge, who stays in touch and follows the careers of many of his former students, can rattle off a dozen others.

"Over the years, Kluge has really inspired students to pursue this," said Prof. James R. Ebert, who has taught geology at Oneonta since 1985. "I think he suggests Oneonta because our philosophy is similar to his — that science is a process, not a body of facts to be memorized."

Professor Ebert has also used art from the Hudson River School to teach sedimentology and historical geology because the artists usually were so careful to get the details right. But even more than that, he said he likes to talk about the old landscape art in his classes as a way of impressing on his students that scientific field work should be thought of as more than just an intellectual or academic enterprise.

"The point is to let them know there are other aspects beyond science — aesthetic dimensions," he said. "Geologists get to be in the field and visit beautiful places that artists have painted."

Mr. Kluge's loves of science and art and the past are also connected with family. He grew up in Ardsley, N.Y., and his father, a high school math teacher and later the principal of Ardsley High School, first brought him camping here in the late 1950's or early 1960's. He remembers the hikes along the artists' trails, and the canoe rides on North Lake at night when the beavers would slap their tails on the water, and how dinners were cooked on the Coleman stove by the campfire.

The night hike to the Mountain House, though, was something he invented, beginning with the first Fox Lane class field trip in 1986. Another ritual that has become part of the trip is that the teachers and chaperons always cook and serve dinner to the students at camp before the Mountain House hike. (The hotel was closed in 1942, and the state burned it to the ground in 1963 after it had become a dilapidated menace.)

"We bring our sleeping pads, or sleeping bags when it's cold, for an hour or two of meteor and satellite watching, identifying stars and constellations, and watching Taurus rise above the eastern horizon in that eternal pursuit of the Seven Sisters across the autumn sky," he said. "And we usually spot a porcupine or skunk on the way back to camp."

Ms. Woodell, now 26, said she had already vowed that the Catskills trip — and especially the night hike to the Mountain House — would continue. When Mr. Kluge decides to retire, she said, she stands prepared to take it over.