It was in the year 1517 that Nicholas Kratzer, or Kratcher, a Bavarian, was admitted at the age of thirty to the new college of Corpus Christi at Oxford, founded by Bishop Fox. His name is on the list of lecturers appointed by Cardinal Wolsey, and he lectured on astronomy and mathematics. Tunstall, writing in 1520, calls Kratzer the "deviser of the King's horologies." He became a fellow of Corpus, and while at Oxford he constructed two sun-dials, one for St. Mary's Church, which stood on the churchyard wall till 1744, and another for the college garden. In a MS. work, " De Horologiis," now in the college library, Kratzer says that many of the directions for making dials were taken from an old book in the Carthusian monastery at Auerbach, near Vienna. Kratzer was a man of a merry spirit, and much beloved. When Henry VIII. asked him how it was that after so many years in England he had not learned to speak the language, he is said to have replied frankly : "Pardon, your highness, but how can a man learn English in only thirty years?"
From The Book of Sun-dials by Alfred Gatty, Eleanor Lloyd