The hypocaust system. The hypocaust system (hypocaustum in Latin) was a heating system used in (wealthy) Roman homes and Roman baths, and the closest thing to central heating today. The hypocaust was a system that circulated hot air under the floor and surrounding walls. Hypocaust construction
CDC: Nearly 9 millon Americans use prescription sleep aids. Nearly 9 million U.S. adults take prescription sleep aids, with use more common among those who are older, female, white and better educated, according to the first government survey of its kind released on Thursday.
How Much Sleep Do We Really Need: Revisited. The National Sleep Foundation released the results of a world-class study that took more than two years of research to complete â an update to our most-cited guidelines on how much sleep you really need at each age. You can read theresearch paper published in Sleep Health.