Stanley Mouse and Alton Kelley's FD-78 is printed in hot red-orange on a flat blue ground: a winged female figure, arms raised to her head, standing inside a ribbon of hand-lettering that spirals down around her body and carries the bill. Collectors know it as the "Angel." The lettering is the kind that rewards patience — you read the poster the way you'd untangle a knot — and when it resolves it says MILLER BLUES BAND / MOTHER EARTH / BUKKA WHITE, September 1, 2 and 3, Avalon Ballroom.

Friday, September 1, 1967 was opening night.

The headliner is a small lesson in how unsettled all of this still was. The poster says "Miller Blues Band." The Family Dog's own listings for the run say "Steve Miller Band." Wolfgang's catalogs the sheet under "The Steve Miller Blues Band." All three are the same group — Steve Miller had come up from Texas by way of Chicago and formed the band in San Francisco in 1966, and it spent its first two years shedding words from its name before settling. This chronicle takes the poster as the artifact of record: on the night, at the Avalon, the top of the bill read Miller Blues Band.

Mother Earth was second. Tracy Nelson's band had also arrived from elsewhere — Nelson from Wisconsin by way of the Chicago folk and blues scene, the group's core from Texas — and had landed in San Francisco earlier that year. Third, and this is the part that makes the bill worth pausing on, was Bukka White.

White was a Mississippi country blues singer and guitarist, born around 1909, who had recorded for Vocalion in 1930 and for Okeh, and who had served time at Parchman Farm, where he recorded for the Library of Congress in 1939. He was rediscovered in the early 1960s by two young enthusiasts who wrote to "Booker T. Washington White, Aberdeen, Mississippi" on the strength of a lyric, and the letter reached him. By 1967 he was playing psychedelic ballrooms in San Francisco, third-billed under two bands whose members had not been born when he made his first records. He was also, as it happens, B.B. King's cousin.

That is the Avalon's particular achievement, and it happened often enough at Sutter and Van Ness that it can pass without comment: a nineteen-sixties light show, a local blues-rock band at the top of the bill, and a man who had recorded "Shake 'Em On Down" in 1937 sitting third on the same poster, playing a steel-bodied National to a room full of people in their twenties.

Elsewhere in the city that Friday the season was equally crowded. Cream were four nights into the back half of their Fillmore Auditorium stand, on Jim Blashfield's BG-80, with the Electric Flag and Gary Burton. Up on Haight Street the Straight Theater had Big Brother & the Holding Company — Janis Joplin's band — with the Southside Sound System and Freedom Highway. Three rooms, three bills, one ordinary San Francisco weekend. But the poster of the day is Mouse and Kelley's angel, and the story of the day is an elder of the country blues opening a rock show in a converted dance hall, six months after the Human Be-In and three weeks before the Summer of Love was over.