Tables and treatises on the computation of the calendar.

SUMMARY: Tables and treatises on the computation of the calendar, astronomy and astrology, in a single hand, with medical recipes added in a variety of later hands. Reference MS8515 This is the substantial remains of a practical manual of late medieval computational science and astrological medicine, that was compiled with some care in the early 15th century. A date of about 1425 seems justified as this is the first date given in both the calendar and tables of eclipses. The script indicates that this manuscript was produced in southern England, probably in London. The calendar is a version of John Somer's Kalendarium, originally calculated from 1403-1507, including tables of algorithms for the conversion of Roman and Arabic numerals and an introduction explaining how to calculate the moveable feasts of the Church. The second page for June onwards is lacking, but information for January-May is complete. References to three abbots of Cluny within the calendar (Odilo - 1 January, Hugh - 29 April and Majolus - 11 May, the latter in red script) indicate that the manuscript was probably connected to one of the Cluniac monasteries in England. This is followed by a method of calculating the movable feasts using the fingers, with prose commentary, often attributed to John of Garland (c.1195-c.1258), ff.9-14v. The first leaf is missing, but almost certainly contained the standard opening found in other surviving copies, as described in L. Thorndike and P. Kibre, A Catalogue of Incipits of Mediaeval Scientific Writings in Latin, 1963, col. 243. Folios 14v-16 contain details of the characteristics of people born under the ascendancy of the sun, moon and each of the planets that were known at that time (Mars, Mercury, Jupiter, Venus and Saturn). This is followed by a treatise on administering medicine according to the zodiacal sign of a person, ff.16-17, which considers the effect of the stars on the four humours of the body, and cites Galen and Isaac Judaeus. The space for a title has been left blank, indicating that the ...