 With mixed feelings about his academic studies, he reunited with his former Egg bandmates for their final album "The Civil Surface" (also in 1974), which consisted of unreleased material written in 1971–72, including what many view as Campbell's masterpiece in the progressive rock canon, "Enneagram".The album was bolstered by two Campbell-composed wind quartets (which featured neither Stewart nor Brooks).During this period, Campbell maintained a connection with the Canterbury scene movement of which Egg had been a part, playing and recording as a support musician for Henry Cow, Hatfield & The North, Slapp Happy and others.