This site, from the Department of History and Philosophy of Science at the University of Cambridge, is a sizeable reference resource for students studying the history of astonomy from ancient times to the Sixteenth Century. The database is divided into three main sections: Instruments, Themes and Personalities, within which are numerous subdivisions, including Early Modern Books, Celestial Globes, Calendar Reform, Weather Prediction, Tycho Brahe and Kepler. Each individual entry contains a short essay together with a brief bibliography and, where appropriate, relevant images (which may be viewed full-page). The quality of presentation is excellent and an index and keyword search facility are also contained on the site.

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