Midnight Cave: The Time Experiment

"Experiences Hors du Temps" is a film by Michel Siffre about his 1962 experiment in a Texas cave concerning the effects of time isolation (human chronobiology). He spent two months underground with no access to sunlight or a clock, and studied its effects on his mind and body. ©Haverand Prod., 1963. (52:07) Interested in cave exploring? Try the NSS (https://caves.org).