On Sunday, August 7, 1966, the Family Dog put Bo Diddley on stage at Longshoremen's Hall with Little Walter and the Sons of Adam beneath him, Bill Ham running lights, and a nine o'clock start. Admission was three dollars.

The poster, FD-20, prints two nights and two prices. Friday the 5th: Bo Diddley and the Sons of Adam, nine o'clock, two-fifty. Sunday the 7th: the same two acts with Little Walter added, and the price up fifty cents. Between them, on Saturday the 6th, the Family Dog ran a separate show at the Avalon Ballroom on its own poster, FD-19. Chet Helms had moved his operation into the Avalon earlier that year, so going back to the old barn on North Point for the Friday and Sunday nights was a decision about capacity — the two rooms ran as one weekend.

That matters, because Longshoremen's Hall is where this whole scene got started. The Trips Festival had happened there in January, and the first Family Dog dances before that. By August the operation had a proper ballroom, so returning to the union hall was a practical decision about capacity, not nostalgia. The poster is a Mouse and Kelley design — Stanley Mouse and Alton Kelley, working as the studio partnership that produced most of the Family Dog's best sheets — built around a found photograph of five men in a rowboat. Who those men were, and where the picture came from, I have not been able to establish. The Denver Art Museum, which holds a copy, catalogs it simply as men in a rowboat.

The bill was a generational collision of the kind Helms kept engineering. Bo Diddley was a Chess Records artist with a rhythm named after him, headlining for a promoter half his audience's age, under a liquid light show. Little Walter — the greatest amplified blues harmonica player who ever lived — is printed second on the Sunday bill, in letters as large as the Sons of Adam's, and he was certainly in San Francisco that week: he was holding down a residency at the Matrix with Quicksilver Messenger Service backing him, which is its own remarkable image. Whether he actually walked onto the Longshoremen's stage on the 7th is less certain than the poster makes it look. The same archivists who list him on this bill also place him at the Matrix that night, two miles away. Both are possible in one evening; neither is confirmed. He had less than two years to live.

The night's real weight is easier to miss. According to Bruno Ceriotti's chronology of the band, August 7, 1966 was the last night of the Sons of Adam — guitarist Randy Holden quit on the spot, and a replacement was in place the following day. Holden remembered telling them he was through "right then, and there." The band's own later account is softer and less flattering to him, suggesting his volume and behavior had grown erratic and that they pushed him out, then regretted it. Both versions exist; the exit is agreed on, the agency is not.

Either way, a band came apart in that hall on a Sunday. Holden went on to The Other Half and then Blue Cheer. The drummer, Michael Stuart, would join Love and play on *Forever Changes*. Their best record, "Feathered Fish," had been written for them by Arthur Lee. They are a footnote now, and on that night they were opening for Bo Diddley and quietly dissolving.