Philip Kyle, a young geologist from Ohio University, was lowered by rope down the vertical wall of the volcano. His beard frosted in the cold but he stayed up all night on the edge of Mount Erebus's inner crater, carefully observing the lake of bubbling lava 320 feet below.

"I was peering down at the lava lake," he recalled, "when this eruption occurred. There was a 30-foot wide gas vent at the bottom of the crater. Molten lava welled up inside and just as it reached the top, it exploded. There was a flash and an incredible noise. It was like standing in front of a cannon. We were running across the floor screaming and there were rocks flying about our heads. A strong blast threw us on the ground."

That was six years ago, and since then Kyle has been back several times to study the 12,450-foot mountain, the only active volcano in Antarctica. This year he is camping on its snowy outer slope in order to plant three seismometers -- "like stethoscopes," he explains -- to listen to the volcano's inner rumblings. The machines send radio signals back to camp.

Few places are as exciting for scientific research as this ice-locked land at the bottom of the earth. From its luminous snowfields to its austere granite peaks, it is a land of mysterious grandeur. But polar science is a hazardous occupation, whether it means siding up to a volcano, diving under a frozen lake in a wet suit, collecting milk samples from an ornery seal or trudging across glaciers to gather meteorites.

In the last 20 years, Antarctica has become one of the world's great scientific laboratories. Oddly enough, it is a good place to learn about the rest of the earth. Kyle's study of Erebus -- one of two volcanoes in the world with an open lava lake -- may help prevent another Mount St. Helen's from taking us by surprise. Studies of frigid winds that spill off the polar plateau teach us a lot about global weather. Research on glaciers here will help scientists predict when North America can expect another ice age. And, since Antarctica has the cleanest air on earth, monitors here take the key baseline measurements of global pollution.

"Being in a remote area has a certain romance to it," said Richard Cameron, a veteran polar scientist. "But you really have to be interested in what you're doing to go out and work under such extreme conditions." Antarctica is the coldest, windiest place in the world. American scientists travel 10,000 miles to get here, but can usually work less than four months a year because the weather is too poor to fly in during the rest of the time. In winter, it is dark around the clock.

In the early 1960s Cameron was in a plane crash here in which six people died -- accidents are not uncommon, given Antarctica's unpredictable blizzards But he keeps coming back. "There's something special about the polar regions," he said. "When I first came in 1956, we drove inland and we didn't know if we would see mountains or not. We are still explorers in a sense. We want to learn more about the earth."

Kyle and the nearly 300 American researchers who come to Antarctica each year are here as much for foreign policy reasons as for the pure love of science, however. The United States is one of 13 countries -- including the Soviet Union and Japan -- who have scientific projects here, mainly in order to keep a political stake in the continent.

Under a 1961 treaty, Antarctica is administered as an international zone and any country that has the money and expertise for a substantial scientific program can take part in governing it. It is an expensive undertaking: Of the $63 million the United States will spend at four scientific stations here this year, only $9 million goes for actual research. The rest pays for ski-equipped cargo planes, helicopters, Navy pilots, wolverine-trimmed parkas, laboratories, snowmobile mechanics, sophisticated radios, deisel generators and other special items necessary for conditions here.

Nonetheless, the $9 million sustains a remarkable variety of projects from oceanography to upper atmospheric physics and even a study or two relating to man, a species unknown here until the arrival of 19th century explorers. University of Wisconsin microbiologist, Elliot C. Dick used McMurdo's isolated winter population this year to test iodine-soaked tissues -- known as "killer kleenexes: -- as a cure for the common cold.

In the shadow of a giant glacier, 60 miles from McMurdo, George M. Simmons, a biologist with Virginia Polytechnic Institute and State University, emerges from the bottom of a lake, dripping in his black rubber wet suit. He is holding a three-foot long glass tube full of dirt and algae. It looks like an unimposing mess, but to Simmons and his fellow Virginians, it is a treasure.

"This is one of the first forms of life to exist on the plant," said Simmons, his breath fogging in the cold. "It was one of the dominant life forces from 500 million years ago to three billion years ago, before the evolution of invertebrates."

The tiny plants are unique on earth today. They have grown under the lake's 15-foot ice cover, reproducing themselves in near darkness, and, in some parts of the lake, with no oxygen. Without fish nor insects to disturb them, they remain in a primordial state. "You drop through that ice and all of a sudden you realize that your eyeballs are the first to look at that material," Simmons said. "It's like a window on the past. It's a creepy feeling."

To collect the algae, Simmons and his Virginia colleagues have melted through the frozen surface of Lake Hoare with a copper coil. They take turns diving with oxygen tanks. As a diver meters the light 36 feet under the ice, and collects the sample, his disembodied voice floats through a radio above him, an eerie sound in the empty valley. The researchers sleep in a Jamesway hut for two days, then return to McMurdo by helicopter to analyze the samples before coming back.

A few miles away, trudging up one of the rare ice-free valleys on the continent, George Denton, a University of Maine geologist, and three companions are searching for rocks to explain the history of past ice ages. They carry sleeping bags and pick axes in their knapsacks, and for eight weeks they will camp out in near-freezing weather, with occasional visits from helicopters to help them move their camp further up the valley.

Only 2 percent of Antarctica -- a land as large as the United States and Mexico combined -- has escaped the smothering embrace of the ice sheet. And it is in these "dry valleys" that Denton is looking for clues as to whether the ice sheet might soon melt into the ocean, thus raising the worldwide sea level and flooding cities such as New York and Los Angeles.

"There is a tremendous debate among geologists about it," Denton said, pausing to trace diagrams with his finger in a snowbank. "We have been studying 20 interglacial periods in the last two million years, and only once did the ice sheet collapse during that time -- 120,000 years ago."

But Denton and a number of other scientists think it might happen again, and even within the next century if man continues to burn coal and oil, thus sending carbon dioxide into the atmosphere. The carbon dioxide could warm up the earth by trapping the sun's rays, thus causing the ice sheet to melt, Denton said.

The harsh conditions of Antarctica provide the closest analogy on earth to life in space, which is why space scientists tested equipment here before the moon shot. In the dry valleys, a Florida State University biologist, E. Imre Friedmann, recently discovered colonies of microscopic plants that live a quarter-inch under the surface of porous rocks -- a form of life which, some scientists speculate, could exist on other planets. The organisms live in a freeze-dried condition during the half-year that the continent is dark.

Several scientists are using Antarctica directly to study space. John Annexstad, associate curator of lunar samples at NASA's Johnson Space Center, led an expedition this season 800 miles out into the Antarctic wilderness in search of meteorites.

"Meteorites are our link to the asteriod belt, the area between Mars and Jupiter," said Annexstad, a rugged explorer who has been on seven Antarctic expeditions. "Someday there is going to be a mission to the asteriod and as much information we can get before we send a spacecraft, the better."

In 1977, Annexstad's associate, William Cassidy of the University of Pittsburgh, found a meteorite no bigger than a man's thumb sitting on top of a piece of bluish ice here. The rock contained amino acids inside and out and finally proved what scientists had suspected -- that these building blocks of protein, essential to life, do exist in outer space. "If we have any link to extraterrestrial life, this would be it," Annextad said.

Annextad and Cassidy pick up the meteorites with teflon tongs and wrap them in plastic to avoid contamination before they can be analyzed in laboratories. Ten years ago, only 2,000 meteorites had been found in history, many by farmers ploughing a field. But since the Japanese discovered some here in 1969, Antarctica has proven the richest burial ground on earth for these messengers from space. Five thousand fragments have been found here, many of them surfacing after being frozen under ice for a million years.

"Most meteorites were formed 4.5 billion years ago when the solar system was formed," Cassidy said. "They have a record of cosmic rays going back a million years. They can tell us what's been going on with the sun."

University of Maryland researcher David L. Matthews is also something of a space explorer: His territory is the plasmapause, a belt 16,000 miles above the earth that can affect global communications signals. Matthews and a group from Stanford University are studying "whistlers," the electro-magnetic waves set off by lightening, which interact with charged particles in the earth's radiation belts. The clearest whistlers, originating in Quebec, happen to land in the Antarctic. And it is easier to listen to them here, because the ice forms an automatic tower for an elaborate radio receiver.

At Siple Station, 1,500 miles from McMurdo, the whistlers "sound like a chorus," Matthews said, "like a flock of birds, or a distant cocktail party." This season, the group is sending balloons and 25-foot-long Nike Tomahawk rockets with sophisticated equipment 150 miles up to learn more about the waves and particles.

The hazards, if not the glories, of Antarctic science, are well described in a little orange manual distributed to researchers each year by the National Science Foundation, which runs the program here. "Never thaw a frost-bitten limb in the field unless it can be maintained at temperatures above freezing," the booklet warns, and goes on to tell the story of a scientist who fell into a snow drift and suffered second-degree frostbite.

Whiteouts, when intense light bounces between clouds and the snowy ground, are especially dangerous. Shadows disappear and all sense of depth and distance is lost. A man can die a few yards from safety in the milky air. "In a survival situation . . . don't eat snow," the manual advises. "You will spend more energy melting it in your mouth than you can afford." It diagrams how to build a cave under the ice, in case one is stranded on the polar plateau, and to rescue oneself by rope from the bottom of a deep crevasse. It recounts the story of a scientist who fell off an ice cliff into the sea and warns, "Keep a sharp lookout for sharks . . . . In a final showdown, use a knife to stab it in the gills or eye."

Antarctic science nonethless has its rewards, not the least of which is the possibility that an adventuresome academic can still discover a new geographic feature and have it named after himself. John D. Rockefeller who donated $100,000 to an early expedition got the Rockefeller Mountains. French explorer Dumont d'Urville named a penguin, the Adelie, after his wife. Margaret Lanyon, a National Science Foundation employe who handles travel arrangements for harassed researchers, was rewarded with Lanyon Peak. Even a New York Times science writer managered to become the eponym of Sullivan's Ridge.