"We're captive on the carousel of time," those memorable lines from Joni Mitchell's "Circle Game," reverberated through Berkeley's Community Theater last Saturday night as Joni, David Crosby, Graham Nash, Neil Young, David Blue, Jackson Browne (and assorted friends) on stage plus 3500 fans out front had a big joyous standing sing-along to end Miss Mitchell's magnificent concert.

It had been the kind of evening every artist and patron wants but seldom gets. From Browne's opening "Take it Easy" refrains, with which he began the performance, on through Miss Mitchell's brief third encore (nearly three hours later) the Berkeley Community atmosphere was the quintessence of "good vibes."

This was Miss Mitchell's first local concert since early 1969. In the intervening time, on records, she has confirmed her remarkable lyric talent and demonstrated a strengthening and broadening of vocal substance.

Saturday's concert indicated another important change in Joni she is now a comfortable, assured woman. The once inconclusive and hesitant delivery, and the unlikeliness of her lyrics, no longer pertain.

She sang in solo with her guitar, dulcimer, or piano accompaniment, for well over an hour before inviting Crosby, Nash, Young, et al, to help her and her enthralled fans bring the concert full-Circle.

There was the lightness of "She's Not Gonna Fix It," the calypso-like structure of "Big Yellow Taxi," the astute social observations of "Banquet," and the relish with which she sang "Carey," a nostalgia piece for her which is steeped in the atmosphere of the Mermaid Cate on Crete.

She has never sung "That Song About the Midway" as well... its words, "pack it in, pack it in," haunted me overnight. A new composition, "For the Roses," which she introduced with some jolting remarks, sings of confetti and critics; power, glory, worship; parties and golden eggs.

The song equates race horses and pop stars. "A thoroughbred Derby-winning horse breaks a leg in a gopher hole and he's shot," Joni noted, "but pop stars shoot themselves sometimes, don't they?"

Miss Mitchell's peculiar intonation and burry, wide-range, voice singing over her often lurching, melancholy, rhythmic base demands attention and her audiences comply.

They know her older, recorded, songs but the new ones (she included a half a dozen) take time to absorb.

Certainly "My Old Man," "Woodstock," "Both Sides Now," and the incomparable "Cactus Tree" and "For Free" were great to hear. That she paced the show perfectly, talked just enough and seemed to have lived and re-lived every situation in her lyrics made the night an especially personal sort of experience for everyone.

"You Turn Me on, on the Radio" is an uproarious new romp, and another new one ("Ballad of Cold Blue Steel," think) has some astonishingly rich chord changes.

Jackson Browne's introductory 50 minutes prior to Miss Mitchell's conquest were uneven but enjoyable. Browne is a likable young Californian who occasionally gets snagged on themes of dope and sex (as have most of his fans, I suspect) but he sings and plays (guitar, piano) fairly well and has written some interesting stuff - "Jamaica." "Rock Me on the Water," "Together in Sin at the Holiday Inn," and others.