The young woman being trussed up at left is proving a scientific point. She is about to spend a night outdoors in the snow—no comforting tent overhead, no campfire or nearby cabin. In fact, her sleeping bag will probably freeze to the snow in the high-altitude, subzero temperatures of Taos, N. Mex. but she will stay cozy and warm inside.
This super-lightweight winter camping equipment—sleeping bags, parkas, mukluks and the big mittens holding the binoculars—is a sharp departure from tradition. The gear is lined not with goose down or feathers but with polyurethane foam, one of the miracle products of this generation. It has been used in many ways, but only recently to insulate people.
This new use of foam may well have been dictated by the times. Camping experts know that nothing will ever replace real fur for winter gear. Caribou, because its hollow hairs contain air cells, is the perfect material, as the Eskimos well know. Reindeer skin also is dandy. But animal skins are expensive, hard to find and—these days—ecologically unsuitable. Foam seems to be the best modern substitute.
Phase One in the battle against severe cold began in 1964 with an electrical engineer, Gil Phillips, walking through the Pecos Wilderness in New Mexico, wearing electric socks inside his boots and freezing his feet. Phillips painfully decided on the spot that boots and socks don't work in very cold weather. Vilhjalmur Stefansson, the Arctic explorer, had made a similar decision years before. "Eskimo boots of sealskin are waterproof but cold," he reported in his book Discovery. "I wore deerskin boots and socks and got them soaking wet. The result was I suffered a slightly frozen heel."
Phillips began to look for a material offering cheap insulating quality (he discounted down as too expensive) and he came up with flexible foam. First he wrapped his feet in layers of foam and then he fashioned outer mukluks, Eskimo style, to wear snow-camping. At 11° below zero his feet stayed warm. Impressed, he next made himself a foam-lined sleeping bag.
Phase Two in the foamy saga was simple enough. Phillips—whose basic motivation was to keep his feet warm and not to make money—handed his idea over to a tiny company called Ocaté, which began producing the foam gear commercially in an abandoned dance hall next to a saloon in Rainsville, N. Mex. The company has since moved to Santa Fe, but it is still a small, relaxed operation. "A foam parka? Make you one in 20 minutes," says Don Reynolds, the company manager, who has sold 12 jackets off his own back to passing hippies on their way to the communes around Taos. Ocaté also has outfitted the Glider Club of New York, made jackets for the Jets and for an anthropology team sent to chilly Sweden by the University of Iowa.
There are now five varieties of foam sleeping bags, parkas, ponchos, mittens and mukluks in 16 colors. Ocaté also is moving into bright orange hunting vests and pale blue underwear—foam long Johns lined with nylon taffeta, light as thistledown.
Reynolds is mad for foam. "We were looking for the perfect material to retain heat and release body moisture," he says. "Of course there is no such thing—except the fur on a living animal. But foam comes pretty close. It can't do everything. Foam can't generate heat—the person has to do that for himself. But a foam sleeping bag will keep the ice out of your bed."
Hypothermia—the lowering of the body's temperature—is the thing that mountain climbers dread most, and the foam bags have probably saved some lives, according to Lute Jerstad, one of the five Americans to have climbed Everest. "When my tent ripped apart on Mount Hood I stayed warm in the bag, and warmth is a key thing for me ever since I got frostbite," he said. "I use the mukluks on boat trips where my feet are in cold water half the time. At least they're warm, even if they're wet."
Contrary to popular supposition, foam does not soak up water like a sponge. Like many plastics, it has a history of being misused. Early foam equipment, too thinly layered, sopped up water until it felt like a hundred pounds on a camper's back. Ocaté's open-cell foam, covered with water-repellent nylon, breathes with the wearer. It will absorb water, if compressed, but one has to lean heavily on it to make it do so.
There are 64 varieties of foam, open cell and closed cell. A Seattle company called Jan Sport makes mountain gear using closed-cell foam, completely waterproofed. Ron Fear, a volunteer safety instructor for the Mountain Rescue Council of Tacoma, Wash., successfully climbed Dhaulagiri II in Nepal last May using the almost weightless overboots, mittens and bivouac bag made for him by Jan Sport.
Before his big climb Fear experimented at home on Mount Rainier with various thicknesses and types of polyurethane foam and discovered, as Phillips had done, that rolls of the one-eighth-inch thickness were wonderful to slide next to the skin as protection against wind chill. "Fantastic stuff," says the climber. "It keeps you alive with your own body heat like a wet suit."
The Last Whole Earth Catalog describes the Ocaté model as the ideal poor man's sleeping bag—and, indeed, $40 for a one-man bag is a competitive price. The bag is hard-wearing and if it does rip it can be repaired with a Band-Aid, unlike the handsome, down-filled bags that spill all their feathers. The Catalog also advises that "rolling the Ocaté is difficult until you get the hang: squish the bag with your knees as you roll it." This does seem to be a minor problem. In the words of the company manager when asked to demonstrate: "Fold it over and then jump on the rascal until it lies flat."