PORVENIR, CHILE — TIERRA del Fuego is an island of wild beauty: snow-covered mountains, virgin forests, frozen lakes, grasslands, and peat bogs in an area the size of Connecticut. The western half, belonging to Chile, has only 10,000 residents, while Argentina's eastern side has about 80,000 inhabitants. This desolate island at South America's southern extreme is also a historic place with names to match. The Strait of Magellan separates it from the mainland, and the Beagle Channel is named after Charles Darwin's boat, which carried the English naturalist through here in 1832. In his journal, Darwin wrote that a ''single glance at the landscape was sufficient to show me how widely different it was from anything I had ever beheld.'' When Portuguese navigator Ferdinand Magellan arrived in 1520, he saw natives gathered around big signal fires and named the island ''Land of Fire.'' Fuegian peoples - the Tahgan, Ona, Haush, Alacalufes and Tekeenica - wore otter and seal skins, ate shellfish and seal meat, and lived in crude huts of branches and grass. ''Man exists here in a lower state of improvement than in any other part of the world,'' Darwin wrote. The native peoples had all died out by the 1930s. TIERRA del Fuego's isolation ended in 1880 with the discovery of gold. At the same time, the government doled out acres of land to sheep herders, who built ranches that still bear such names as Harmony, New Land, and California. In 1910, the first loggers began limited operations on the edges of the vast lenga forests. But by the 1940s, most lumber enterprises had been closed down by the global depression. They didn't return until the mid-1980s when the Chilean government of military dictator Gen. Augusto Pinochet began selling off large tracts of the island's lenga forests for as little as 50 cents an acre. Chile's only large settlement is Porvenir, a town of dirt streets, wooden homes, tin roofs, high prices, and low wages. Trillium's forest-harvesting project is a favorite topic here these days. Most of Porvenir's 4,000 residents hope it will eventually boost the town's depressed economy. ''The government does nothing for us. We have been abandoned,'' says Rafael Raicahuin, an employee of the Las Rosas Hotel. ''If Trillium opens for business, many people will leave Porvenir to work for them ... including me.''