The quest for the great white shark -- born of vengeance in Peter Benchley's novel "Jaws" -- now has become an earnest scientific activity at some of the nation's leading public aquariums. But the great white cannot be held captive.

"There isn't an aquarium anywhere that wouldn't give its eyeteeth to display one of these animals," said John H. Rupp, one of several dozen shark experts meeting last week at the National Aquarium in Baltimore. "The problem is that as soon as you get them in a tank they die."

Several other shark species have survived quite nicely in captivity for years. But great whites, for all their reputation as ferocious killers, turn belly-up within hours or days.

Of the 40 known attempts to keep great white sharks in tanks, the greatest success was achieved in 1981 by Sea World in California, which kept one alive for 16 days.

"They look like they're swimming around just fine and then they seem to run out of gas," said John D. Hewitt, deputy director of San Francisco's Steinhart Aquarium.

Experts in shark husbandry conceded at the meeting that their interest in keeping great whites is paradoxical. Sharks draw large numbers of visitors to aquariums because of the mythology suggesting that they are, as some have put it, "nature's killing machines." "Jaws" made the great white the shark's shark.

Yet every major aquarium takes pains to tell visitors that sharks are no more rapacious than other predators such as lions, and that attacks are extremely rare -- much rarer, for example, than bear attacks.

"We're probably cutting our own throats when we try to dispel myths," said Rupp, who keeps sharks at the Point Defiance Zoo and Aquarium in Tacoma, Wash. "As soon as we get our message across, people will probably stop coming and the funding for shark research will probably dry up."

As shark husbandry specialists from every major aquarium in the country listened, Hewitt described a series of increasingly elaborate attempts over recent years to transport captured great whites to the Steinhart Aquarium and provide intensive medical attention to relieve the stresses of capture and transport, only to see them die within hours every time.

Before the shark can be put in the aquarium it must endure several hours of travel from the site of capture, usually a fishing boat in whose net it has become entangled.

The shark is put into a coffin-shaped box that contains a constant flow of water charged with oxygen. Great whites, like many sharks, cannot take in water by "breathing" alone. They must swim with their mouths open to keep water flowing over their gills, a phenomenon known as ram ventilation.

When ordinary shark boxes seemed inadequate, Hewitt and his colleagues designed a new one with a harness that holds the shark so it faces a jet of oxygen-rich water flowing into one end of the box.

On the theory that stress and struggling may upset the animal's blood chemistry, Hewitt has developed an intravenous "drip" containing salt, sugar and other chemicals in proportions equivalent to those of a normal, healthy shark.

On the first attempt, Hewitt said the shark was rushed to the Steinhart's big tank on the theory that the sooner it could start swimming again, the better. The fish swam strongly at first but, in five hours, suddenly died.

"Then we realized maybe we shouldn't be rushing them," Hewitt said. "They've been through a tremendous struggle in the nets and maybe they need time to recover."

He said that although the sharks usually seemed listless and near death when retrieved from the fishing nets, they improved once they were in the shark boxes to get oxygen and the intravenous fluids.

The next time, the great white shark was kept in the box for 40 hours. Like its predecessor it seemed to gain strength steadily. Every time anyone came too near the box, the great fish would thrash its tail, splashing half the water out of the tank.

Convinced that the animal had regained its strength, Hewitt released it into the big tank. After five hours, it died.

On yet another try the shark was treated much the same, but transferred to an intermediate tank where it could be fed, on the theory that the animals need to replenish their energy. Although held in a harness, the shark ate 40 herring over a period of nearly four days.

Once in the main tank, it died.

"I don't know where we're going wrong," Hewitt said. "This is all seat-of-the-pants stuff, more intuition than hard science."