Materials & Methods:
"The experiment that brought sleep science to global attention was one that Kleitman performed on himself. In 1938 he and a graduate student, Bruce Richardson, descended into the depths of the Mammoth Cave in Kentucky, where they spent the next 32 days a quarter of a mile from the nearest chink of daylight, maintaining an artificial sleep-wake cycle of 28 hours. They kept time with alarm clocks, took their temperatures regularly, grew beards, stashed chamber pots in the cave recesses, ate fried chicken and smoked cigarettes, all on a rigid timetable of nineteen hours awake followed by nine asleep."
