 Among the most prominent works to build on Michell's ideas during this period were Janet and Colin Bord's "Mysterious Britain", which used them in its presentation of a gazetteer of ancient sites, and Paul Screeton's "Quicksilver Heritage", which argued that the Neolithic had been a time devoted to spiritual endeavours which had been corrupted by the emergence of metal technologies.Michell associated with many individuals active in this ley-hunting community, and in July 1971 was one of many attendees at a ley-hunters picnic held at Risbury Camp, the largest outdoor gathering of the movement since 1939.In May 1969 Michell established a group known as the Research Into Lost Knowledge Organisation (RILKO) with his friends Keith Critchlow and Mary Williams.