The system of all phenomena in space and time; the totality of physical reality. It is both a scientific and philosophic concept appearing in all historic eras. (Webster 2d; Dr. James H. Cassedy, NLM History of Medicine Division)
History, 18th Century
Time period from 1701 through 1800 of the common era.
History, 19th Century
Time period from 1801 through 1900 of the common era.