Reply #42: ... This particular astrolabe, dated 1326, resembles the instrument described in Geoffrey Chaucer's

[struggle4progress]

Treatise on the Astrolabe. The treatise is addressed to 'his little son, Lewis' and uses the year 1391 for its calculations. Like the astronomical and astrological references in Chaucer's Canterbury Tales, it demonstrates his unusually well-informed interest in contemporary science ...
http://www.history.ac.uk/richardII/astrolabe.html

... why should the leprous abbot of England's premier monastery spend his declining years designing an elaborately accurate clock? ... Richard of Wallingford owed much to the Benedictine Abbey of St Alban ... The Prior supported him and eventually sent him to Oxford, where he gained his BA after six years of study at the age of twenty-three in 1314 ... The Abbey Chronicles tell us that Richard himself felt that he had neglected theology at Oxford, preferring to concentrate on mathematics and astronomy ... North has fully described the clock's workings; Lehr gives excellent diagrams of the gears and the clock face ...
The wheel with 120 teeth ... rotates once in 24 hours, and drives everything else.
The wheel with 115 teeth rotates once in 23h 56m 4.12s, only 0.03s longer than the sidereal day, so within one part in 3 million of the correct value, turning the star plate ...
The wheel with 331 teeth is not circular, but shaped in such a way as to drive an image of the sun with the sun's true equatorial velocity ... compensating for the equation of time ...
The moon is represented by a sphere which rotates to show the lunar phases, and whose mean motion is within 1.8 parts per million of the true value ...
http://www.nicholaswhyte.info/row.htm

... The first significant astronomy at Oxford achieved international renown before the Reformation ... John Ashindon or Ashinden, also called Eastwood (in one reference of 1338) was according to Anthony Wood the greatest mathematician and astronomer ever produced by Merton College. He inspired a succession of students applying themselves to mathematics and astronomy over the next 150 years. Most of their work was removed from the college library in a cart during a Visitation in the reign of Edward VI, when such books and manuscripts relating to natural science were regarded as profane or worse, and were burned or sold as scrap paper ... At that time the best astronomical tables predicting the positions of the Sun, Moon and planets for astrologers and navigators, were the Alphonsine Tables produced at Toledo in 1272. Ashindon and Rede are believed to have used astrolabes to make observations from the south part of the city wall that is also the boundary of Merton College garden. They made improved calculations including the mean longitude of each planet for every 20 years, and published tables adapted for the latitude of Oxford that were a distinct improvement on the Spanish tables ...
http://www.freewebs.com/sochistastro/oxfordshire.htm