SAN FRANCISCO, OCT. 23 -- When the call went out that Humphrey was stuck in the shallows again, San Francisco people climbed into their automobiles and hurried down to the water's edge to wave their binoculars at him and cheer him on.

"I just wish we could talk to him," said an AIDS researcher named Hilary Brown.

"I just feel so helpless, seeing him out there," said a windsurfer named Jayne Hagen, who offered to put on her wet suit and climb in to help.

"Come on, Humphrey," said Leslie Levy, who works as a volunteer with the California Marine Mammals Center, and was poised tiptoe on the rocks with her eyes fixed on the great shiny curve of black before her. The curve of black moved, twitched, roiled the shallows around it. Across the water came a sigh, a big wet sound, and then a thin spray of water. A gray pectoral fin lifted and dropped. On the rocks, the people applauded.

There is only one whale on the California coast who is known to the local population on a first-name basis, and that is because he is a whale who keeps breaking away from the other guys and swimming the wrong way and generally serving as a 40-foot metaphor for many charming and troublesome things like myopic independence, or myopic curiosity, or possibly just myopia -- maybe Humphrey, people volunteered from the shoreline today, can't see where he's going. Or maybe he's lonely. Maybe he likes the attention. Many theories were being offered, as the people gathered anxiously on the shore, and the scientists weren't able to offer much by way of illumination.

"It's just an idiosyncrasy of this whale," said Marc Webber, the Marine Mammals Center's science administrator. "He seems to like coming into shallow water. Why, we don't know."

When last heard from in a really big way, Humphrey the humpback whale spent three weeks in an errant trip up the Sacramento Delta, which is a narrow bay-into-river part of Northern California and not the sort of place a whale ought to be spending his time. Dozens of boats and thousands of people became intensely involved in the effort to coax Humphrey back out to the sea, and it was only after many false efforts -- banging on pipes, herding with rubber rafts, and generally making a great ruckus behind him -- that Humphrey was turned around and pointed out in the direction of all the other whales.

Since then he has been spotted many times, usually in places where whales are supposed to be. An all-points bulletin was released on Humphrey after the Sacramento Delta adventure, just to keep him under surveillance: "The California Marine Mammals Center is on the lookout for a missing humpback whale (A K A 'Humphrey')," the bulletin read. "Last seen November 4, 1985, steaming out the Golden Gate and heading toward the open ocean."

Tne APB listed the suspect's most readily identifiable characteristics: distinctive white markings on the dorsal fin and the tail. "That is as individual to them as your fingerprint is to you," said Peigin Barrett, director of the Marine Mammals Center. She said the Coast Guard had gotten word on Sunday that there was a whale in San Francisco Bay, and that when whale experts looked down by helicopter on Monday, they recognized the white markings and saw that Humphrey was about to do it again.

And now he was beached, the brown water barely up to his dorsal fin, in a narrow channel just south of Candlestick Park.

"He's breathing," somebody said.

"Wonder how long he can go without eating?" somebody said.

"Eating's no problem," said a retired banker named Roger Otto, who had brought along a fine brass spyglass. "He's got enough body fat to go without food for quite a while. That's what they used to hunt them for, for fat."

Otto lifted his spyglass, and shook his head, and talked a little about mysteries, and the bonds between species that cannot quite communicate with each other. "Maybe he's an Edison of the whale species," Otto said, "doing research. Coming in to see people."

Humphrey sighed again, and fluffed up the water. All around him men and women bobbed in wet suits, splashing water over his back, waiting for the high tide. Rubber rafts, little putt-putt motors fixed to their sterns, circled in the water as men and women prepared to play out the netting and rope that was supposed to attach Humphrey to a waiting Coast Guard pilot boat.

"This is a terrible cul-de-sac he's gotten himself into," Webber said somberly. "Last night there was almost no water in this whole channel. We'll do whatever it takes to get him out of the bay tonight, if we can."

Webber said Humphrey was in no danger of starving to death, but that the whale is a creature that cannot tolerate lying in warm sun and shallow water -- that his skin might become sunburned, that the heat might warm his body too much, that his body weight might crush his own organs. "Maybe he has some feeding preference that brings him in to shore," Webber said. "Humpbacks are very versatile whales in the way they feed. They can eat krill, or they can eat fish, the anchovies that school close to shore around here. It may be that his preference is to feed on the fish, and he may have gotten lost in the eddies and not have been able to find his way out."

Webber spoke rapidly into his walkie-talkie, squinting out at the milling rafts. The water under Humphrey's body began to bubble, where an air compressor was pushing water to loosen him from the mud. The men and women in wet suits worked delicately, moving the lines and nets about, and then a white line was pulled to the Coast Guard boat and began slowly to tighten.

There was a heaving motion in the shallows, and then the dorsal fin moved. A cheer broke out on the shore. The fin moved more, slowly now, but forward. "It's moving!" someone shouted. "He's moving!"

The dark length of the whale began to surface in the water, the Coast Guard boat pulling steadily back. A spray of water shot into the air, with a kind of joyous lip-raspberry sound that carried to the rocks, and then suddenly the wonderful curve of the back rose up and plunged and rose again, and the ropes dropped away to let Humphrey swim straight for the sea.

Now the cheers were loud, and there were whistles too, and applause -- but then someone shouted, "No! Look! No!" Undulating through the water, swimming still, Humphrey was headed straight for the right bank of the channel.

"Turn," someone cried desperately, but Humphrey didn't turn. He stopped. His nose was jammed into the right bank. He was beached again.

Webber and the television cameramen darted over the rocks, scrambling to the inlet where Humphrey lay. "I have a 3-year-old son who reminds me of Humphrey," a photographer muttered as she elbowed past the onlookers. "Everything his own way." A volunteer from the Marine Mammals Center waved her hand ... wet suits circled the whale again, looking anxious. From the Coast Guard boat came the voice of a man watching the time on the high tide: "We're running out of water," he said. "We've got 15 minutes."

Slowly, the people in wet suits came back with the nets and rope. The rope played out toward the Coast Guard boat again. It was very quiet now, the television cameras whirring, the women shushing their children where they squatted on the rocks. The rope tightened again, and the Coast Guard boat began to back out into the channel. Humphrey's back lifted a little. He flapped his pectoral fin again. The water trailed around him, and he began to move -- backward, this time, but spouting as he went.

"Don't turn!" someone cried. "Do it this time!" cried someone else. His bulk moved left, moved right, began pointing back into the channel he had just left, but everybody on shore was screaming at him now, and waving their arms: "Wrong way! Wrong way!"

The motorized rafts surrounded Humphrey, the men and women inside banging long pipes underwater to make a kind of curtain of sound that might drive him back. The Coast Guard boat nosed gently beside him, like a well-trained dog with a recalcitrant sheep. The dorsal fin hesitated for an instant, and then finally, gently, the men and women calling and banging and pointing as though a proper compass might be all that was needed, Humphrey pointed toward San Francisco Bay and began to swim.

It is a long way from Candlestick Park to the Golden Gate Bridge, and it was apparent right away that the flotilla of Humphrey boats were about to put in a long night. "Come on, you big palooka," a Marine Mammals Center volunteer murmured, his binoculars trained on the receding black shape that was all that was visible of Humphrey. He was swimming in the wrong direction when he reached the open bay, but at least he was swimming.