His hair has grown out. There are sharp creases furrowing each side of his face. And he is even more given now to spending hours brooding in a tent in the desert. Some say he is schizophrenic, others that he is manic depressive. He has a delicate stomach.

At 37, however, Col. Muammar Qaddafi has consolidated control of his revolution, tightening the reins on the oil riches that have plucked this sprawling North African state from historic and geographic obscurity.

This September, the enigmatic colonel celebrates the 10th anniversary of the coup that brought him to power.

"He has done it and gotten away with it, and the reality is it's still a one-man show," says one Western diplomat here.

Another observer says, "There are no apparent challenges to him; he can do anything he wants."

A third analyst brushes Qaddafi's achievements aside saying "This is another Arab dictator with flair."

Judgments of Qaddafi have always been extreme, and often as harsh as the climate that rules this desert nation.

As the mercurial colonel whisks abroad in his plushly appointed Boeing 707 with meals catered from Paris, or travels through the streets of Benghazi in a simple caravan of British Range Rovers, he can claim some achievements.

He has irrevocably reversed the politics of the Maghreb -- the strip of Mediterranean countries running along Africa's nothern shores. Ten years ago, the pro-Western monarchy headed by King Idris counted almost no Libyans in the powerful court positions.

Today, Libya is Libyan-run, albeit by Qaddafi's murky revolutionary circle.

Libya's per capita income has become one of the highest in the world. It has one of the Third World's most ambitious education programs, with nearly a third of its population in school. It has a petrodollar-fueled economy tht can afford automated desert green-houses projects growing the world's most expensive tomatoes, as well as the latest Soviet-produced Mig fighter aircraft.

It can afford to buy -- as Qaddafi tried unsuccessfully to do through an emissary to China in 1971 -- a nuclear weapon.

Qaddafi and Libya usually conjure images of terrorist intrigue or petrodollars pouring in from Western consumers such as the United States -- which buys 40 percent of Libya's oil -- or Italy and West Germany and then out again to favored Moslem clients.

Yet, Qaddafi, like any other ruler, must look to his home front if he is to last long and carry out grand or illusory designs in the international arena.

"There is no doubt that the whole country has changed enormously, and for most Libyans it is a better place. The question is, how much of this is Qaddafi, and how much is the oil money?" says one experienced Libyan-watcher here.

The answer, in a way, is as elusive as Qaddafi's own personality.

One thing is certain, however. Qaddafi mounted his putsch against former King Idris just as Libya's oil money began coursing through the economy.

"Most of the people see the good times coming with Qaddafi," says one State Department official.

Perhaps ironically, the stuff of Qaddafi's ambitious multibillion dollar five-year plan, with the requisite steel mill, high technology communications system and quilt of infra-structure spending, was largely inherited from the monarchy.

Libya's prosperity, nevertheless, cannot be denied.

Two decades ago Libya was literally the World's poorest country, the post-war era's Bangladesh. Infant mortality was a seemingly insoluble problem.

Libyans can now affort to support large families, typically 10 or more. Half the population is 13 or younger, and there are no reasons to constrain Libya's birth rate, now one of the highest in the world.

During decades of Italian occupation -- Libya was Mussolini's "fourth shore" -- Libyans were subjected to the same kind of apartheid policy applied to South African blacks today.

It's a different story now. Libyans look to more than 400,000 foreign workers for manual labor, servants or trained technicians, including Italian construction workers whose grandparents once had land holdings here.

Signs of the new affluence bear out the dry statistics.

Streets are clogged with traffic -- late model Mercedes, Peugeots or Fiats. Japanese pickups have replaced camels. And the once common horse-drawn carts and taxis are now an oddity.

Long considered North Africa's doormat -- "palm tree Arabs" one Egyptian calls them disparingingly -- Libyans now travel at will. This year for example, 25,000 visas for Britain will be issued here, compared with 7,000 in 1974, the year oil prices quadrupled.

Discussions about Libya, however, inevitably return to Qaddafi.

Qaddafi and Islam. Qaddafi and his ill-defined mix of socialism and Arab nationalism.Qaddafi and terrorism. Qaddafi and the atom bomb. Qaddafi's next move.

Petulant, given to outbursts on every issue, Qaddafi is an amalgam of styles, a dizzying concert of the dramatic and austere.

"He is still a semi-nomad, an army officer who seems to like the look of a lot of people trailing after him," says one experienced observer here.

Instead of the palatial state houses like those chosen by Egyptian President Anwar Sadat or Irag's Saddam Hussein, the colonel prefers a barracks atmosphere, and he still receives visitors in a tent, lolling on his side like a tribal chieftain.

And instead of the exquisitely tailored European suits favored by Sadat and Hussein, Qaddafi usually sticks with spiffy military regalia, ribbons and an occasional swagger stick.

As for Qaddafi's national vision, another experienced anaylst of Libyan affairs says, "Without oversimplifying it too much, Qaddafi really wants a country of devoted army colonels and majors drawing rations from a mess."

This model -- the British officers' mess -- is in many ways the touchstone for Qaddafi's own brand of socialism and the direction he has plotted for much of Libya's social and economic life.

Over the years, though, Qaddafi has drawn his personal image to try to evolve from a military dictator to a socialist thinker. The transition has not gone smoothly.

Unlike other revolutionary manifestoes, Qaddafi's Green Book (modeled in part on the late Chinese leader Mao Tse-tung's Little Red Book) was not written in prison, or during long years of revolutionary plotting. The colonel's coup came off in 1969, and Libyans did not get their first look at the Green Book until 1976. Other installments followed in 1978, and earlier this year.

Aside from the Green Book, Qaddafi has promulgated his own personality cult through the government-controlled press.

The campaign was stepped up earlier this year. Now Qaddafi's pictures are everywhere, portraying him in a Gen. MacArthur-style military pose wearing sunglasses and military regalia and sitting astride a white Arabian charger, or dressed in a white robe. He is the revolution's Marlboro man.

Freeway drivers are treated to bill-boards emblazoned with quotes from the Green Book. Television and radio programs offer hours of daily coverage to the colonel's latest speech supporting the right of "exploited peoples to combat bloodsuckers, Zionists and American imperialists in Asia, Afirca and Latin America."

Underpinning Qaddafi's philosophy of government is his intense personal devotion to Islam -- some say "religious fanaticism."

While Islamic social restrictions are not as severe here as in Saudi Arabia, Qaddafi banned liquor, shut down nightclubs and sought to bring Islamic values into Libyan government as soon as he took charge a decade ago.

He has also committed great energies to proselytizing his own version of Islam. A few years ago in a nationally televised speech he called on the Moslem world "to go to Japan and transform it into an Islamic state."

"This is not a hard task," the colonel told his followers.

Qaddafi likewise drew great personal satisfaction from his conversion of Uganda's Idi Amin and Emperor Bokassa of the Central African Empire to Islam. He witnessed their initiation rites, and his enthusiasm was not undercut by suggestions that Amin's and Bokassa's new faith was cynically tied to aid commitments.

As for the colonel's devotion to the Koran, years ago in an interview with Le Monde, Qaddafi said: "You'll find the answers to all your questions" there -- "Arab unity, socialism, inheritance rights, the place of women in society, the inevitable fall of the Roman empire, the destruction of our planet following the invention of the atom bomb."

Underlying Qaddafi's political theories, and even his commitment to "islam, there is another reality: The colonel is the beneficiary of his own policies.

His third tract, rejecting both capitalism and communism, also along the way provides the colonel with a rationale for forbidding the establishment of any political parties.

And his path to socialism -- actually a variant of a mixed private and public sector economy -- succeeded in systematically wiping out independent civilian power centers that could pose a threat to Qaddafi's rule. It also allowed Qaddafi to cut back sharply foreign dominance of Libya's economy, although American oil companies still benefit from a special relationship.

Enthusiasm for Qaddafi's program is thin here.

"The middle class doesn't like it, so Swiss banks, or confine themselves to the booming shadow economy," says one observer.

To stem capital flight, a nagging problem since Qaddafi came to power, Tripoli has imposed strict currency controls which Libyans go to great lengths to circumvent.

Still another trend that has set back the economy is Qaddafi's draft edict, committing young men 18 to 35 years old to military service. This move, which is unpopular in some circles, has slowed down Qaddafi's pace for "Libyanization," or increasing Libyan control of the economy.

The draft calls have also cut into the ranks of the small managerial class, further weakening the economy.

Some weeks ago a French woman living in Tripoli visited the electric power company saying she had not received a utility bill in a year and was afraid her power would be cut off. She was told not to worry about it, because the man who handled accounts and ordered cutoffs in service for delinquent bills had been drafted.

Another trend Qaddafi has loosed is the uncontrolled squeeze on housing, stemming from a declaration in the Green Book on abolishing wages and rents.

"They are bound to vanish so that no person will be a parasite on another," Qaddafi wrote.

Afterward, Tripoli published Law 4 in effect saying that whoever occupies a home owns it and forbidding rental or leased properties.

The result was a shock wave of confusion through the economy. Libya's private housing construction boom came to a halt, adding further pressure to an already tight real estate market.

More serious, it touched off a wave of limited, but violent, incidents.

Libyans on vacation returned to find their rented homes occupied by other families. Caretakers working for American oil company employees were beaten up, as Libyans tried to lay claim to rented houses.

Libya's economy also is plagued by many of the problems typical of Third World countries, but not expected in one of the oil cartel's wealthiest states.

There are recurring shortages of consumer and some capital goods, largely the result of Qaddafi's government takeover of all import and export activities. To compensate for this, Libyans turn to a small black market, or more likely return from trips to Europe laden with vacuum cleaners or pasta machines.

The spot shortages of some products are matched by instances of extravagance and development overkill that characterize a few of the wealthy oil-exporting nations.

Tripoli's new international airport, for example, has elegant marble floors. Much of the new industrial equipment unloaded at ports hastily dredged a few years ago is beyond the skills of Libya's labor force.

The military offers even more flagrant examples. Western intelligence reports indicate that Libya's nascent air force has nearly three planes for every fully trained pilot.

Assessing Libya today, let alone predicting its future, is an uninviting task since the country is ruled as much by Qaddafi's whims as by the paradoxes of life here.

Even a European journalist sympathetic to Qaddafi's ideals calls the Libyan experience a "perverse revolution."

A less apologetic longtime resident here draws comparisons with Evelyn Wagh's satirical creations.

"It's a muddledom country and always will be," he says.

Asked about the prospects for 10 more years of Qaddafi fule, one analyst said: "The threat most likely would be from one man with an assassin's bullet, or perhaps a challenge from the armed forces; but so far there are no signs of it," despite the disgruntlement over recent setbacks in Uganda.

For now, at least Qaddafi appears to have the whip hand over Libya's future. CAPTION: Picture 1, Pickup trucks are a more common sight in oil-rich Libya these days than Bedouin's camel caravan. By J. P. Smith -- The Washington Post; Picture 2, Muammar Qaddafi, Always fervent in his adherence to Islam, is building a cult of personality in Lybia. MacArthur-like portrait of Qaddafi in Tripoli By J. P. Smith -- The Washington Post; Picture 3, he wears traditional Libyan dress at 1978 Algiers summit; Picture 4, prayer at Tripoli mosque. By Francois Lochon -- Gamma