Middle Ages (5th-15th Century)

The history of cometary astronomy is naturally divided into five major periods, the transitions being marked by important new insights. Before 1600, comets were essentially considered to be heavenly omens and were not yet clearly established as celestial (astronomical), rather than meteorological phenomena in the terrestrial atmosphere. Then followed two centuries of mostly positional measurements with emphasis on the motions and the orbits, lasting until the early 19th century, when the era of cometary physics was inaugurated, in particular by the passage of P/Halley in 1835. The next major step forward occurred in 1950 with the sudden emergence of the modern picture of comets as being essentially very old solar system objects made of primordial ice and dust, generally in unstable orbits and intensively interacting with the solar electromagnetic and corpuscular radiation. Finally, the space missions to P/Giacobini-Zinner in 1985 and especially to P/Halley in 1986 provided the first in situ observations of comets and dramatically widened our scientific horizon, but also posed many new questions which are yet to be answered.

This is a partial list of some of the leading Muslims. Major Muslim contributions continued beyond the fifteenth century. Contributions of more than one hundred other major Muslim personalities can be found in several famous publications by Western historians.

An unusually fine collection of manuscripts representing primarily British and American literary, political, and historical figures has been received from a number of donors. These include letters from Mms. de Sévigné, Voltaire, George III, Virginia Woolf, Sherwood Anderson, and John Steinbeck

Traditional Chinese medicine is thousands of years old and has literally more than a billion satisfied customers. Many of its treatments and teachings are based on the effects of Chi, a mystical form of bio-energy.

All are invited to visit the Hill Monastic Manuscript Library. The Library is open to the public, free of charge. No credentials or letters of recommendation are required for visiting or using the Library's resources. Visitors coming from a long distance or for extended stays, or those needing special assistance or consultation with staff members, are encouraged to write or call in advance.

Our Mission: The Virtual Museum of Natural History was established to provide instant, ready access to current biodiversity data to all interested users via the Internet at no charge

This page introduces the fossil evidence for human evolution in China. At present it includes a catalog of Chinese human fossil remains consisting of: a picture gallery of important fossil specimens, maps detailing the distribution of human fossils, and a time line; links to other relevant sites dealing with paleontology, human evolution and Chinese prehistory; and other resources which may be useful for gaining a better understanding of China's role in the emergence of humankind. More features will be added in the near future

This index page links to material relative to the origin and history of male circumcision. Material is indexed in chronological order of publication.