The small, barefoot man in black T-shirt and blue jeans barely rates a second glance from the other Starbucks patrons in downtown San Rafael, although he is one of the men who virtually made the '60s. Because Augustus Owsley Stanley III has spent his life avoiding photographs, few people would know what he looks like.

The name Owsley became a noun that appears in the Oxford dictionary as English street slang for good acid. It is the most famous brand name in LSD history. Probably the first private individual to manufacture the psychedelic, "Owsley" is a folk hero of the counterculture, celebrated in songs by the Grateful Dead and Steely Dan.

For more than 20 years, Stanley -- at 72, still known as the Bear -- has been living with his wife, Sheila, off the grid, in the outback of Queensland, Australia, where he makes small gold and enamel sculptures and keeps in touch with the world through the Internet.

As a planned two-week visit to the Bay Area stretched to three, four and then five weeks, Bear agreed to give The Chronicle an interview because a friend asked him. He has rarely consented to speak to the press about his life, his work or his unconventional thinking on matters such as the coming ice age or his all-meat diet.

Sporting a buccaneer's earring he got when he was in jail and a hearing aid on the same ear, he keeps a salty goatee, and the sides of his face look boiled clean from seven weeks of maximum radiation treatment for throat cancer. Having lost one of his vocal cords, he speaks only in a whispered croak these days. At one point, he was reduced to injecting his puree of steak and espresso directly into his stomach.

"I never set out to change the world," he rasps in recalling his early manufacture of LSD. "I only set out to make sure I was taking something (that) I knew what it was. And it's hard to make a little. And my friends all wanted to know what they were taking, too. Of course, my friends expanded very rapidly."

By conservative estimates, Bear Research Group made more than 1.25 million doses of LSD between 1965 and 1967, essentially seeding the entire modern psychedelic movement.

Less well known are Bear's contributions to rock concert sound. As the original sound mixer for the Grateful Dead, he was responsible for fundamental advances in audio technology, things as basic now as monitor speakers that allow vocalists to hear themselves onstage.

Says the Dead's Bob Weir: "He's good for a different point of view at about any given time. He's brilliant. He knows everything."

Bear, whose grandfather was a Kentucky governor and U.S. senator, grew up in Los Angeles and Arlington, Va. He was thrown out of military school in the eighth grade for being drunk and dropped out of school altogether at 18. He managed to get accepted to the University of Virginia, where he spent a year studying engineering. By 1956, he was in the Air Force, specializing in electronics and radar.

Later, Bear studied ballet, acting and Russian, worked in jet propulsion labs as well as radio and television, and then entered UC Berkeley in 1963, but lasted less than a year.

Then he discovered acid.

He found the recipe for making LSD in the Journal of Organic Chemistry at the UC Berkeley library. Soon after, Bear began to cook acid.

The Berkeley police raided his first lab in 1966 and confiscated a substance that they claimed was methedrine. When it turned out to be something else -- probably a component of LSD -- Bear not only walked free but successfully sued the cops for the return of his lab equipment.

By the time he made a special batch called Monterey Purple for the 1967 Monterey Pop Festival -- Owsley Purple was the secret smile on Jimi Hendrix's face that night -- "Owsley" was an underground legend.

In December 1967, agents arrested him at his secret lab in Orinda. The "LSD Millionaire" headline in The Chronicle prompted the Dead to write the song "Alice D. Millionaire." In 1970, after a pot bust in Oakland, a judge revoked Bear's bail, and he served two years at Terminal Island near the Los Angeles Harbor.

"If you make some, you've got to move some to get some money to make it," he says now. "But then you had to give a lot away to keep the street price down. So anyway, I'm sort of embedded in this thing that I'm tangled up in. ... Just as soon as it became illegal, I wanted out. Then, of course, I felt an obligation."

Bear, chemist to Ken Kesey and the Merry Pranksters, was involved with the Dead almost from the band's beginnings at Kesey's notorious Acid Tests. Bear was the Dead's first patron and, briefly, their manager. He bought the band sound equipment and began to use the Dead as a laboratory for audio research.

"We'd never thought about high-quality PAs," says the Dead's Weir. "There was no such thing until Bear started making one."

Bear made the first public address system specifically dedicated to music in 1966. If he was the first concert sound engineer in rock music to take his job seriously, his habit of making tape recordings of the shows he mixed also gave the Dead an unprecedented archive of live recordings dating back to the band's first days. Many of Bear's tapes have been turned into albums.

Bear has always lived in a quite particular world. "He can be very anal retentive, on a certain level, on a genius level," says Paul Kantner of Jefferson Airplane. "I've seen him send his eggs back three times at Howard Johnson's."

His all-meat diet is a well-known example. When he was younger, Bear read about the Eskimos eating only fish and meat and became convinced that humans are meant to be exclusively carnivorous. The members of the Grateful Dead remember living with Bear for several months in 1966 in Los Angeles, where the refrigerator contained only bottles of milk and a slab of steak, meat they fried and ate straight out of the pan. His heart attack several years ago had nothing to do with his strict regimen, according to Bear, but more likely the result of some poisonous broccoli his mother made him eat as a youth.

As a sound mixer, Bear holds equally strict viewpoints, insisting that the most effective rock concert systems should have only a single source of sound, his argument quickly veering into the realm of psycho-acoustics.

"The PA can only be in one spot," he says. "All the sounds have to come from a single place because the human brain is carrying around the most sophisticated sound processing of any computer or living creature. It equals the bats that fly by echo. It equals the dolphins. It equals the owls that hunt at night without any daylight at all. It is a superb system for locating and separating one sound from everything else."

Bear left Northern California in the early '80s, convinced that a natural disaster was imminent. He predicted at the time that global warming would lead to a six-week-long ultra-cyclone that could cover the Northern Hemisphere with a new ice age. Determining that the tropical northern side of Australia would be the most likely region to survive, Bear made a beeline for Queensland and says he felt at home the moment he set foot on the new continent.

"I might be right about the ice age thing," he allows. "I might be wrong."

Old friends express shock that Bear would ever even admit to that possibility, but, if not exactly mellowed in his old age, he has found room to accommodate other points of view.

"He's come a long way," says Wavy Gravy, who visited Bear in Australia this year. "He used to be real snappy and grumpy. Now he can be actually sweet."

His four children are grown. He has five grandchildren, and his oldest son, Pete, in Florida, just became a grandfather, making Bear a great-grandfather for the first time. His other son, Starfinder, a veterinarian, hosted a party for him last month at his Oakland home attended by the old Dead crowd, a tortoise and a caged iguana. He has two daughters, Nina and Redbird, and maintains his own Web site (www.thebear.org) where he sells his sculpture and posts various diatribes and essays.

He keeps up with the music scene -- he singles out Wolfmother and the Arctic Monkeys as new bands he likes. "Any time the music on the radio starts to sound like rubbish, it's time to take some LSD," he says.

Owsley Stanley (he legally dropped the "Augustus" 40 years ago) has also not joined the ranks of the penitent psychedelicists who look on their experiences as youthful indiscretions.

"I wound up doing time for something I should have been rewarded for," he says. "What I did was a community service, the way I look at it. I was punished for political reasons. Absolutely meaningless. Was I a criminal? No. I was a good member of society. Only my society and the one making the laws are different."

At the hilltop San Anselmo home where Bear had been house-sitting, pretty much all available space was taken over with his belongings. He squatted over the piles, trying to figure out what to ship and what to take with him. Two days before his flight, it looks like he'll need every minute.

This time, he was extending his stay to catch his old friends Jorma Kaukonen and Jack Casady of Hot Tuna play at the Fillmore. But when he left for the airport the next day, he got as far as Sausalito before he discovered that he had left the briefcase with the tickets back in San Anselmo, and the trip home was postponed for another week.

"I even said, 'I wonder what I'm leaving behind this time?' before I left," he says, somewhat sadly.