The experience of Tibet is helpful for the first-time visitor to China, for Tibet is, in many respects, China scraped bare. The struggle for survival has been more arduous in this 2-mile-high plateau than in the Chinese hinterland, so the feat of the Communist rulers in making Tibet almost self-sufficient in food is all the more striking.

But because it was the last piece of the mainland to come under Peking's control, its final subjugation coming in 1959, a decade after the fall of the Kuomintang government, the methods by which communism has organized and controlled this society are less subtle and more obvious to the visitor.

And because there are sharp racial, ethnic and religious differences between the Han Chinese and the Tibetan people, this is also a laboratory test of the Communists' ability to avoid the sins of cultural "imperialism."

In 3 days, a visitor on a closely escorted tour can gain no more than a few clues to these three dimensions of the Tibetan experience. But because Tibet is so clsoed to American eyes - fewer than 20 Americans have visited this city in the last 28 years - even those clues may be worth recording.

AS GOOD A PLACE as any to begin is where our party - headed by George Bush, the former head of the U.S. Liaison Office in Peking - began its first full day in Lhasa. It is in the garden of the Norbu-Linka Palace, from which the 14th Dalai Lama, the last of the Buddhist god-kings who ruled Tibet for 5 centuries, fled in 1959, after the failure of a revolt against the Communists who had occupied Tibet 8 years earlier.

It is Oct. 1, National Day across China, marking the 28th anniversity of Mao Tse-tung's proclamation of the People's Republic of China. Our Tibetan hosts told us at the initial briefing that, "We will see some of the relics of the Tibetan past and join the masses to see how they celebrate National Day," in short, a meeting of the two cultures - Tibet past and Tibet present.

The "masses" are just beginning to stream into the park, when we arrive in our motorcade of sedans. We are ushered immediately into the palace. The briefing, delivered by a Chinese-speaking Tibetan and translated into English by one of the Foreign Ministry officials who has accompanied us from Peking, begins with a bit of history:

"After the peaceful liberation of Tibet [not so peaceful that it was not protested to the United Nations by the Dalai Lama in 1980-81] our party arrived at the policy of education and unity, rectifying the policies of the Dalai Lama. But the Tibetan ruling nobles under the 14th Dalai Lama, against the will of the people and the policy of the party, carried our rebellious activities in 1959. At that time, Norbu-Linka Park became the headquarters of the rebellion. After the quelling of the rebellion, Norbu-Linka Park came back into the hands of the people as a sightseeing and recreation place."

While there have been well-authenticated reports that the U.S. Central Intelligence Agency was making arms drops into Tibet at the time of the 1959 rebellion, our hosts make no reference to that fact - perhaps out of consideration for Bush; who headed the CIA for a year when he came home from China in 1975.

On the other hand, their statement that the ornate palace has come "back to the hands of the people" is open to question. None of the several thousand Tibetans ventures into - or near - the palace while we are wandering around the park and Chinese cadre from a perimeter around the building while we are inside.

OUR TOUR of the palace is largely devoted to enjoyment of the rich fabrics and art works the Dalai Lama left behind. But certain display cabinets show documents going back to the 14th Century, linking Peking to the affairs of Tibet. These are letters which we are told show how Ming Dynasty emperors authorized and protected Tibetan religious customs. There is even a letter from the despised Chiang Kai-shek to the 14th Dali Lama, recognizing his religious and temporal authority.

Over barely beer, our Tibetan guide tells us ,through the double translation that "all these historical relics show that officials of Tibet and the Dalai Lamas themselves, if they are to be legal, have to seek the approval of the central government or the emperor."

"Was approval ever denied?" one American asks. Pause for the double translation of question and answer. "No. They did not refuse it."

The park - if not the palace - belongs to the people. Tibetans in conical hats and bright cloaks, with many children, are out for a holiday. In the past, they had a fall harvest, the Lingka, which lasted 3 days. The Chinese rulers have shifted the date so it coincides with National Day.

AN ENCOUNTER between Lowell Thomas, 85-year-old broadcaster and world traveler, and Jen Jung, the party boss of Tibet:

Thomas:"When I was here last [in 1959] there were some nunneries. Are there still?"

Jen Jung: "There are still a few."

Thomas: "The head nun of one of them was called the Sacred Sow." The Chinese laugh.

Jen Jung: "She has many children now."

Thomas: "She got her name because in an earlier time, when the Chinese approached Tibet, she used her magic and turned her nuns into pigs and enabled them to escape."

Jen Jung shakes his head and rolls his eyes in disbelief: "There was such a legend about another time, when the troops advanced from Nepal, not the hinter land of China . . . but the idea of a living Buddha is really a superstition, like fairies that are drawn from heaven. It is a superstition like the rumour the Dalai Lama spreads [from his exile in India] that the people in Tibet don't have enough to eat and can hardly live here. Now you have come and you can see for youself."

AT THE TEMPORARY stage erected in Norbu-Linka Park for National Day entertainment, it appears to be largely a production of Chinese for an audience dominated by the green uniforms of the People's Liberation Army (PLA) and the blue of the party cadres. Our guide, a pretty, apple-cheeked Chinese girl of perhaps 19, says she came here last October in response to the call for educated youths "to help backward regions. I expect to live my life here."

"Are you learning Tibetan?" she is asked.

"No, it is very difficult language," she says in fluent English.

LIKE THE PARTY of Americans led by James Schelsinger which visited Tibet a year ago the first such Americans to see the country since 1949, we are marched through a grim buildingcalled the Tibetan Revolutionary Museum. It is a stark, revolting depiction of the alleged atrocities of the old regime.One is tempted to view it as an example of the crudity of the propaganda tools the Chinese feel they must use to wrench the Tibetan peasants out of the theocratic past and into the socialist future.

The only difficulty with the theory is that there are no Tibetans in the museum when we go through. And the dozen times we pass the building during our 3 dys in Lhasa, the front doors appear to be shut tight to the crowds of holidaying people thronging the streets.

But the impact on the American guests is powerful and sobering. Severed hands, human skins, skeletons of children reportedly buried alive in monasteries, instruments of torture, dramatically lit dioramas showing the monks' slave trade and the crushing of serfs' rebellions . . . all this stuns the group.

"When the lamas were reading sutras, " our guide solemnly assures us, "they were actually burying small boys alive . . . they used human skins to make their drums . . . our aim is to teach the younger generation not to forget the previous generations' suffering. Chairman Hua visited the exhibition personally in 1975," a blessing worth than that of Buddha.

The guide: "We are very inexperienced in arranging such exhibitions and would welcome your suggestions and critism."

An American: "The display is very powerful, but it is not clear what the chronology is. Did these atrocities occur in the distant past or quite recently?"

The guide: "Most of the antrocities pictured here occured between 1938 and 1959. The girl who was burned alive to make a statue was in 1956."

An American: "You must have some memories of your own of the Dalai Lama's period. Did you experience such things yourself?"

The guide: "My parents suffered from such brutality, but because I was a small boy, I did not have that experience. But I did not have any shoes or trousers to wear, just rough cloth, and I had many cracks in my feet."

IN THE EVENING, before a prodigious 14-course banquet, we are briefed by Tien Pao, vice chairman of hte Revolutionary Committee of the Tibetan Autonomous Region and Lang Chien, chairman of the Lhasa Revolutionary Committee or mayor. Unlike Jen Jung, the Chinese boss of Tibet who made a brief appearance earlier, both these men are Tibetans. Tien Pao begins:

"Great changes have taken place, earth-shaking changes from the old regime. But compared to the provinces of the hinterland, we are far behind. Tibet was the last to be liberated in mainland China. In the first stage, we mainly concentrated on building roads and united front work with the People's Liberation Army."

The road net to China has made substantial progress, but the first rail line has yet to be completed. When Jen Jung was asked earlier in the day when it might be finished, he dodged.

"it depends on the state plan and the progress of the project," he said. "It will go through the high plateau and many problems must be studied and overcome."

"Then in the next 10 years," Tien Pao said, "we engaged in democratic reform," meaning the establishment of collective farming "and construction. Really, we have had only 12 years of construction and yet we have solved the problems of food and production. There are no unemployed and no beggars in Tibet.

"Under the guidance of Chairman Mao's brilliant policy for minorities we achieved self-sufficiency for food and grains in 1974." [This claim is challenged by American intelligence sources.] "Of course," he added, "The state [Peking] continues to give us a small amount of assistance in rice and broad beans, which are in short supply in Tibet."

TIEN PAO then speaks enthusiastically of another area of growth - population. The Chinese practice strict birth control methods among their own people, but not among the minority races - particularly in underpopulated areas like Tibet. Population, Tien Pao says, "has increased over 500,000 and we have a lot of kids here now."

I takes a series of questions to pin him down on those figures. It appears that he is reckoning from a population base of 1.2 million people in 1960 to 1.74 million today, with most of the growth coming, he says, "in the last 10 years or so." According to U.S. sources, the official Tibetan population figure reached 1.3 million people in 1953 and was revised upward to 1.4 million people in 1974. It is unclear whether the two sets of figures are consistent.

THE QUESTION of the immigrant - or Han Chinese - population is even more elusive. "It is not as high as 20 per cent," Tien Pao says, when an American refers to one Western estimate. "There are 120,000 Han staff members. No Han people have really settled here. There are two patterns among the Han migrants. Some come for an indefinite period to work and they stay until their health is not so good." [Presumably as a result of the altitude.]

"In the second category are doctors, technical people, engineers and the like. They come for 2 or 3 years at a time and then are replaced by others in the same category recruited from their province," apparently in a kind of quota system.

"Of course," he continues, "there are certain cases where a Han man has married a Tibetan woman or vice versa where they stay indefinitely. There is a party secretary here from Shanghai. He came as a veterinarian to treat the animals and married a Tibetan girl, but he speaks perfect Tibetan so he is regarded as one of us. I myself married a Han girl."

"Did not a group of 1,000 or so permanent Han settlers arrive within the past year?" an American asks.

"The information is reliable," Tien Pao says, not bothering to explain the contradiction to his earlier statement. "Chairman Mao issued a call for educated youth to serve in the countryside and autonomous regions so we received some graduates and demobilized cadres. That information was published in your own country."

THE OTHER SUBJECT of some sensitivity in the briefing is the relationship between the two groups, the Han and the Tibetans.

"In most areas of Tibet," Tien Pao says, "the cadres are composed of people of various nationalities. The Tibetan cadres participate in managing both local and state affairs." With great pride, he mentions two Tibetans in the Peking bureaucracy and says. "There are five alternate members of the Central Committee from this region - only one of them of Han nationality."

Tibetan youths, he says, now serve as volunteers in the PLA in increasing numbers. "In ordinary circumstances, we overfulfill our quota. People consider it an honor."

An American asks about the makeup of the Tibetan Autonomous Region's Revolutionary Committee, and Tien Pao says, "Tibetans are an absolute majority." The American asks for the numbers. He looks a bit embarrassed and there is a hurried conference with his colleagues. "We will have to supply those to you," he says, and we go into dinner. The figures are never forthcoming.

According to Tien Pao, "In the early period after the liberation, there were about 120,000 monks left."

When the Schlesinger party was here a year ago they were taken to two monasteries and saw a few elderly monks. We are taken to no monasteries and see no monks.

Jen Jung says, "There are very few lamas noadays. Many people have left the religious circle; some have taken other jobs, some have gotten married and had kids." Later Tien Pao adds, "There are several thousand monks left but the young people do not wish to become lamas. With the growth of knowledge and science, they have come to know religion is a sham."

The disappearance of 120,000 monks in a generation is a remarkable, if not a sinister, development and just how it has happened is not clear, but you remember a photograph in the Revolutionary Museum. It shows PLA soldiers holding a group of lamas at gunpoint during the 1959 rebellion. The monks have their arms up high and they look very frightened.

THE KEY GOAL in Tibet is increased agricultural production. "Our industry is backward," Tien Pao says, "so we emphasize agriculture and the industry that produces simple working tools."

Our glimpse of progress in agriculture is provided by the Tung Ka People's Commune, the same one visited by the Schlesinger party. We are welcomed by some of the 1,124 commune members, gaily dressed and lined up to applaud us and welcome us with drums and cymbals.We sit in the same social hall described by Robert L. Bartley of the Wall Street Journal, a member of the Schlesinger party, under the same heroic pictures of Stalin, Lenin, Marx, Engels, Mao and Chou En-lai.

The statistics are identical to those given Bartley a year ago: an almost fourfold increase in the number of catties per mu produced in the basic crops of highland barley, wheat, broad beans and rapeseed since liberation days.

"We also have two tractors, one hand tractor, one thresher, 11 seed machines and 36 horse-drawn wagons," the head of the commune's revolutionary committee says, to work what is about 375 acres of land.

AFTER THE BRIEFING, with black tea and milk, we walk through an apple orchard and are invited to visit typical homes. Obviously, this is a showcase commune, and, from the road, it looks much more advanced than many others we pass. But our look inside one of the houses opening off a central courtyard shows how close to the survival level even the more advanced Tibetan peasant lives.

The floor is dirt; the walls, whitewashed stone. One bare light bulb, unlit, hangs from the ceiling. The home consists of one room, perhaps 18 by 14 feet, with a curtained-off storage closet and an alcove just large enough to hold a bed.

The family, according to our hostess, consists of her husband, herself and three daughters, the oldest 9 years old. There is no source of internal heat. The wife cooks outside on a small stone fireplace-stove with a stone windbreak. The girls sleep on the couches on which we are sitting. Overhead are pictures of Chairman Mao and Chairman Hua. The yak-butter tea she serves us is hot and rich.

OUR LAST VIEWS of Lhasa are of song, dance and pageantry. At the commune, a troupe of such quality that one is at least slightly skeptical of the claim they are commune youngsters performs a series of dances on an open stage. In one, six boys dance in celebration of the construction of a hydroelectric station. At the climax, they form a pyramid, and the top boy triumphantly mines the action of screwing in a light bulb.

That evening, acknowledged professionals of the Tibetan Dance Company perform for us and an audience dominated by PLA uniforms. The first number shows the red sun rising over Tibet and the last celebrates a bountiful harvest.

In between there is no deviation from the theme that the Chinese liberators have brought abundance and progress to Tibet.

THERE CAN BE little doubt of the advance that has been made. Although Lowell Thomas may mourn for the vanished grandeur, the rich costumes and lavish gifts of the Dalai Lams' court, the pre-1950 Tibet was an autocratic anomaly in the modern world.

It was a theocratic oligrachy, consuming whatever wealth was produced in a backward region, while preventing any step toward modernization, even the introduction of wheeled carts.

The Chinese have brought roads and schools, improved farm techniques, an infusion of outside captial and expertise. Through the PLA and the cadres, they have opened the first avenues of advancement for at least some of the peasants. But they have done so at the price of substituting their own system of social controls for that of the monks.

In our rooms, many of us have copies of an unclassified CIA study of "The Intergration of Tibet," published earlier this year. It asserts that "although the Chinese are now in complete control of Tibet, their situation is uneasy. The majority of Tibetans stubbornly cling to their belief in the Dalai Lama and in their religion, despite Chinese declaration that it is reasonable and punishable by imprisonment or death . . . The Tibetans distrust the Tibetan cadres because of their duplicity . . . The most pervasive feeling among Tibetans, however, is one of resentment toward Han chauvinism, which is expressed at all levels."

One cannot judge the accuracy of those statements after such a short visit. But returning from the propaganda ballet, you pass beneath the walls of the Potala, the mountain-top winter palace of the Dalai Lamas, whose rich interior is preserved intact by the Chinese as a museum of the old regime.

Huge loudspeakers have been installed on its walls, and they are blaring down on the city the martial music to which modern China marches, from dawn until well after dark.

The fortress of the old theocratic despotism thus has been coverted into a giant Wurlitzer, blasting out the hymns of Tibet's new religion. No matter who controls the Potala, it seems, for the peasants and workers below, there is no escape.