SEOUL -- It takes a visitor no time at all to see that Seoul is no longer the struggling capital of a desperately poor Third World country. The streets are clogged with handsome Korean-made cars and the air is filled with the dust of skyscrapers under construction. A giant statue of a drill bit (yes, a drill bit) stands before the Chamber of Commerce, celebrating the nation's relentless march toward industrial prosperity. Beggars are practically extinct.

But a visitor may soon be reminded that, on the other hand, this isn't Baltimore or Tulsa, either. The old women roasting snacks of silkworm chrysalis provide a clue. So do the carts of pressed-squid snacks and the open-air acupressurists.

Beneath the Kyobo Building, where many of the West's most powerful banks and other financial houses have set up shop, a woman earns her living with two little birds in a cage and a box of fortunes. If you drop 100 won (about 12 cents) in the cage and tell the birds your birthday, one of them will hop out through the bars, pick up a fortune with its beak, and hop back into its cage. (Someone named Kim will loom large in this reporter's life next month, according to avian sources.)

A few blocks away, a small crowd gathers on a street corner, listening to a sales pitch. A grizzled man proudly displays a terrarium crawling with Olympic-size centipedes. For about $12, the man says, he will drop 10 of the vile-looking creatures into a bottle of vodka, where they will die, ferment and -- when imbibed by some lucky buyer -- cure backaches, neck aches and other ills beyond the power of modern medicine. No one asks whether the vodka without the centipedes might accomplish as much, but this foreign observer is pleased to note that several Koreans look queasy, too. Sales are not brisk.

AT DUSK in Seoul, as in many Asian cities, the street stalls appear, offering dumplings or shellfish under a naked light bulb. In this city of drill bits and hard work, though, some of the stalls offer more: a 19-inch Samsung or Goldstar color television to entertain patrons as they slurp their noodles.

A casual stroller through the crowded streets would hardly take Seoul to be the site of a continuing people's revolution. Mostly gone, at least for now, are the wall posters that chronicled South Korea's peculiar mix of ritual and rebellion, the posters that urged mass revolution while cautioning protesters not to interfere with pedestrians. The tear gas no longer lingers in the dust, and while there is no evident bitterness, there is no euphoria, either. Koreans have had their hopes raised before, only to have military coups dash them.

A young accountant heading home at 9 p.m. offers a glass of rice liquor to a visitor at an outdoor stall and speaks hopefully about his country's push toward democracy. But still, as the conversation turns to politics, he looks over his shoulder and lowers his voice.

SEOUL, OF COURSE, is to be host to the September 1988 Olympic Games, and the city has prepared for the occasion with single-minded pride and devotion.

Stadiums and dormitories, highways and subway systems have been constructed well ahead of schedule for what South Korea views as its debut among developed nations.

Recently South Korea's pride was jarred in the Olympic arena, though. The national plan for "this glorious festival," as President Chun Doo Hwan recently called it, doesn't stop with being a gracious host; South Korea intends to bag at least 10 gold medals for itself.

But at the 1987 World Student Games in Zagreb, Yugoslavia, this summer, closely watched as a harbinger of Olympic success, the South Koreans limped away with only one silver and one bronze. "ROK {Republic of Korea} Shamed," read a headline in the English-language Korea Times. The Zagreb university games "brought dishonor on the Olympic host," the Times reported, describing a "humiliating, worst-ever record."

Rumors circulated that Seoul's soccer players had refused to play all-out unless they received bonuses, or at least exemptions from the military draft; their coach denied it.

The local press did find a bright spot: North Korea, with two bronze medals, finished slightly behind the South. The athletes, in the great Korean tradition, vowed to work twice as hard from now on.