If you were looking for a non-Scientology explanation for a perceived decline you probably don’t need to look much further than communal living arrangements at a farmhouse in Pembrokeshire, where mixed media experiments with Malcolm Le Maistre and David Medalla's Exploding Galaxy troupe added new influences, and, arguably, diluted the blend of influences. The Inquisitive Reader can find evidence in a film about the ISB, Be Glad For the Song Has No Ending. A mixture of documentary footage and a fantasy sequence called The Pirate and the Crystal Ball, it was shot for the BBC TV arts programme Omnibus, and subsequently reissued on video and DVD.
The next couple of albums, 1969’s Changing Horses and 1970’s I Looked Up were either marking time or gradually slipping, depending on where you sat. A new communal base back in Scotland (at Glen Row near Innerleithen) and continued experimentation with exotic instruments, colourful stage costumes and surreal theatrical sketches and dancers from the Stone Monkey troupe came to a peak with U, Williamson’s multi-media event at London's Roundhouse, followed by a double album containing the songs from the stage show.
Joe Boyd called it a disaster, stopped managing them and headed back to the USA and a job with Warner Brothers. The band left Elektra Records and signed with Island, releasing the soundtrack to the Be Glad... and Liquid Acrobat As Regards The Air, regarded by some as their best recent album, but I started to lose interest around this point.
Rose Simpson was replaced by Malcolm LeMaistre in 1971, around the time Heron recorded a well-received solo album, Smiling Men with Bad Reputations, and Licorice was gone a year later, replaced by Edinburgh jazz musician Gerard Dott. Williamson produced his own solo album (Myrrh), and further line-up changes resulted in what was, to all intents and purposes, a fairly standard amplified rock band. Their final albums were disappointing, and Island dropped them in 1974.
At that point disagreements between Williamson and Heron were close to irreconcilable, and they split in October 1974, with Williamson moving increasingly into traditional Celtic styles and storytelling. Heron formed a rock group, Mike Heron's Reputation, later abbreviated to Heron.
From the late nineties and into the early years of this century there were various reunions, with and without Williamson and his wife, Bina.