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.
Several human studies have measured the effects of melatonin supplements on sleep in healthy people. A wide range of doses has been used, often taken by mouth 30 to 60 minutes prior to sleep time. Results have been mixed. Some evidence suggests that melatonin may work best for people over 55 who have insomnia.