For the past three decades 8,000 pounds of fiberglass has been "sounding" from the ceiling in the Life in the Sea Hall of the National Museum of Natural History (NMNH). It is the most stupendous proxy animal the museum has ever created. But at 92 feet in length and 34 feet in height, it no more than does justice to the dimensions of the huge creature it represents-the blue whale.

The blue is the largest animal that has ever lived. In real life some blues reach 100 feet, which makes them longer than an apatosaurus. Weighing in at some 150 tons, one blue whale is heavier than 25 full-grown African bush elephants. In death the creatures once provided meat for dogs and humans; oil for lighting, margarine and face cream; glycerin for munitions.

Even so, the great size and speed of blues (at up to 25 knots-or 29 miles per hour-they went faster than whaling ships could follow), plus the fact that they sank swiftly when killed at sea, protected them somewhat during the first four centuries of the whaling industry. Then, in the late 1860s, Svend Foyn perfected a highly effective harpoon cannon that featured an exploding head. Worldwide whale protection did not set in until almost a century later, and the years in between brought these giant mammals to near ruin. During the 1930-31 season, for instance, 29,410 blue whales were killed in the Antarctic. An estimated 350,000 blues have been killed in the 20th century.

The whales' great scarcity and sheer size have always posed considerable problems for museums wanting to display full-size specimens. As A. E. Parr of the American Museum of Natural History rather delicately pointed out in 1963, "Since whales do not perch, the problem of presenting them in their living form was a good deal more complicated than bird taxidermy."

That is why the huge creature that now awes visitors in the Sea Hall of the National Museum of Natural History-the second blue whale to be displayed there in this century-is not a stuffed whale. Or even a model made from measurements taken direct from a dead whale by NMNH scientists. The Smithsonian's first life-size museum whale, however, which the current whale replaced, was done from a dead whale. And a terrible fuss it turned out to be. To get it, Frederick True, then Smithsonian's curator of mammals, had to dispatch a small team of taxidermists and paleontologists and numerous barrels of plaster of paris to a whaling station at Balaena, Newfoundland. That was in the spring of 1903.

They waited for weeks. When at last a dead whale, 78 feet long, was secured, it took weeks more of "greasy, laborious and puzzlin" work to make plaster molds of the whale and then cut away the flesh. The skeleton was saved for shipment to Washington. The skull alone weighed three tons. To make plaster casts, they had to manhandle flukes 17 feet across. Flippers tipped the scales at 800 pounds apiece. The whole mess, some 26,550 pounds of bone and mold, was shipped to Washington.

When it went on display in 1904, flanked by a life-size model of a tyrannosaurus that, by comparison, looked about the size of a black Lab retriever loping alongside, it was a wonder.

By the 1950s, though, a growing trend in museum chic called for the display of animals looking as active as possible in a facsimile of their natural habitat. Despite its anatomical correctness, critics said, the 1904 model, with its flippers outstretched like stubby wings, did look a bit like a sausage coasting along in a low flight pattern. A new, improved action whale was needed.

The new Smithsonian whale was to be modeled on the wooden-ribbed, plaster of paris whale then hanging in the British Museum. The British helpfully shipped to America 34 small templates made from their model. These were enlarged at NMNH to form a skeletal wooden whale around which the final model was molded. The Smithsonian's whale outgrew the British version by at least a foot-briefly becoming what a local journalist described as the "big-gest whale in captivity."

Even without having to wrestle with a flesh-and-blood whale cadaver, the construction and mounting of the new Smithsonian whale was an extraordinary challenge-as well as a dangerous chore. Overseeing the work was the late A. Remington Kellogg, a brilliant, irascible vertebrate paleontologist and a stickler for detail. Smithsonian whale modeler Michael Friello remembers that the blowhole and other parts of the blue whale model had to be recast again and again. Kellogg often explained that he was hoping to retire as soon as the job was properly done. Admonishing the crew to hurry up, he would swear and say, "You'll keep me working forever."

Friello remembers that the eight-man crew of carpenters, a shipwright and plastics experts who built the whale, eventually hoisting it up to a midair position, clambered up and down the web of scaffolding more than 30 feet above the ground, without hard hats or safety belts, for four years.

A cabinetmaker, Friello was put in charge of cutting oval wooden frames-like those used to shape the fuselage of model airplanes-and laying longitudinal strips over them to create a skeleton for the whale's body. Two layers of thick fiberglass mat were applied over plywood nailed to the frames. Then Friello crawled inside the whale and tore out all of the supporting wood-to keep the model's weight down to a mere 8,000 pounds. As a last act, he and his mates painted their initials inside the whale's condo-size mouth.

In 1963, the same year that blue whales gained some measure of international protection, Natural History's huge new proxy whale was finally installed where it is today, permanently arched in an arrested dive, seeming to plunge downward over the heads of awed visitors.

Despite A. Remington Kellogg's eye for detail, the spectacular model has not been free of controversy. Blues feed near the surface by opening their immense jaws (the top hinge pops up like the top of a silent butler) and engulfing thousands of gallons of water along with myriad small, shrimp-like crustaceans called krill. Mouth and throat are accordion pleated to be expandable, the better to take in more water and krill. With the throat fully expanded, a whale's front end is bulbous and swollen. As the next step in the feeding process, the whale closes a fine-meshed screen of baleen at the front of its mouth and expels all the water. The nourishing krill are conveniently caught by the baleen netting.

For centuries, whales were depicted as having bulging throats-based on blurry surface sitings and dead whales, whose throats were often distended either by gases caused by decomposition or by compressed air pumped in to help float them after they were harpooned. The blue whale diving down at NMNH visitors has just such a throat. For the first decade or so of its display life, this was regarded as a lifelike touch. But by the late 1970s, an increase in scuba diving and underwater photography began to provide new information about the look and behavior of blues in action. Among such was a fact that whale experts at NMNH find embarrassing: after feeding, blue whales usually spew out their extra water before they dive. A model of a blue that is both diving and bulbous with water, experts say, shows an improbable situation.

On the heels (or flukes) of that information came a few other cosmetic inaccuracies. Its skin is too smooth, critics complain. The epidermis of real whales shows the ravages of time, scars from shark bites, assorted cuts and scabs, whale lice and barnacles.

If critics have their way, by the turn of the 21st century yet another whale model, this time warts and all, will succeed the first two. Meanwhile, just as it is, the sheer size and bulk of A. Remington Kellogg's creature can still take the breath away and plunge the mind into the mysteries of the briny deep.

By Adele Conover