A Planetary Table of Chillingworth, in a Collection of Astronomical Treatises and Tables

Believed to have been made for presentation to Henry VII, this manuscript contains astrological tables and treatises along with some other texts. A team of three artists created its decoration, varying with first- and second-rate renditions of later 15th century English painting and highly skilled work in Flemish style. An inscription on one of the pages gives the date of completion (30 June 1490) and the name Johannes Wellys, thought to be the scribe. Henry VII was the earliest English king known to have a library. A luxury illustrated book on astrology would have been desirable for a king because the stars were believed to exert powerful influences upon human character and affairs.

The Oxford almanac tables of John Chillingworth provided formulae for calculating the phases of the moon and movement of the sun. Tables such as the one on this side were used as aids in astrology but also in medicine because of the belief that the body and its humours were in tune with the movements stars and planets. Diagnosis and treatment of illness often included calculation of planetary and astral positions. For a king, the tables would be an instrument of power and control and a symbol of his position in the centre of the cosmos.