Friday, August 18, 1967 was the second night of a four-night Quicksilver Messenger Service stand at the Avalon Ballroom, with Melvin Q and the Other Half warming up.

Quicksilver in the summer of 1967 were the great unrecorded San Francisco band. The Airplane had two albums out, the Dead had one, Big Brother had one — Quicksilver had signed to Capitol and would not release anything until the following spring. What they had instead was a live reputation, built in exactly this room, on John Cipollina's vibrato-heavy guitar and a two-guitar interplay with Gary Duncan that people came back for. Booking them for four nights at the Avalon was Chet Helms betting on a band the record shops could not yet sell.

The poster is FD-76, by Jack Hatfield, who made very few concert posters in his career — his known handful includes FD-87, BG-103, BG-104, and the Magic Mountain piece. This one is a blue-on-white line drawing of two figures beneath a canopy of foliage, printed on white index stock, closer to an engraving than to the poster-shop psychedelia around it.

A four-night booking for a band with no record is a bet, and it is worth understanding what Chet Helms was betting on.

Quicksilver had formed in 1965 around Dino Valenti, who was arrested on drug charges almost immediately and spent much of the band's formative period in prison — so the group that actually developed was Cipollina, Gary Duncan, David Freiberg and Greg Elmore, working out an interlocking two-guitar style in front of Avalon and Fillmore audiences over roughly two years without a contract that produced anything. Cipollina's tone is the part people describe first: a Gibson SG through Standel and Fender amps with five Wurlitzer horn tweeters stacked above them, played with a heavy vibrato arm, producing something closer to a voice than a guitar. It did not sound like anyone else, and it did not survive to record particularly well, which is part of why the band's reputation rests so heavily on people who were in these rooms.

By the summer of 1967 they had finally signed to Capitol. *Quicksilver Messenger Service* came out in May 1968 and *Happy Trails*, largely live and largely the Avalon repertoire, in 1969. The four nights on FD-76 fall in the gap: known locally, unavailable everywhere else.

The Other Half, second on the bill, were a Los Angeles-by-way-of-Seattle band whose guitarist Randy Holden would later join Blue Cheer. Melvin Q — listed by the Family Dog only for the 20th — is the kind of name that appears once in the venue lists and then vanishes from the record entirely.

Jack Hatfield's poster deserves its own note. He made very few — FD-76 and FD-87 for the Family Dog, BG-103 and BG-104 for Graham, and a Magic Mountain piece — and then stopped. FD-76 is a blue-on-white line drawing on white index stock, two figures under foliage, drawn with the patience of an engraving. Set beside the saturated colour and dissolving letterforms of the sheets around it in the series, it looks like it wandered in from another century. It is one of the quieter pieces in the entire Avalon run, and its designer is remembered by catalog number rather than by name — the same fate as Roger Weil, and a reminder that the numbered series was made by far more hands than the five or six that became famous.