“The Meditator,” a personal isolation tank fashioned from 12 pentagons decorated with photo collages. “You may find the sensation akin to that mystical communion with nature that you experience when alone in a forest,” according to Popular Science writer Ken Isaacs in November 1970. At popsci.com, they’ve republished a photo gallery with enough detail that serenity-seeking DIYers in 2012 can once again roll their own.