Nicholas Kratzer

Nicholas Kratzer (1487? – 1550), also known as Nicolaus Kratzer and Nicholas Crutcher, was a German mathematician, astronomer, and horologist. Much of Kratzer's professional life was spent in England, where he was appointed as astronomer to King Henry VIII.

Nicholas Kratzer
Nicholas Kratzer, 1528 painting by Hans Holbein the Younger
Born	1487? Munich
Died	1550
Occupations	Mathematician Astronomer Horologist

Life

Born in Munich in 1486 or 1487,^[1] Kratzer was the son of a saw-smith, and was educated at the Universities of Cologne (B.A. 1509) and Wittenberg. He came to England in 1516 and established himself as part of the artistic and scientific circle around Sir Thomas More.^[2] Kratzer tutored More's children in mathematics and astronomy and More introduced him at court in much the same way as he had their mutual friend Hans Holbein, who produced a portrait of Kratzer. In the same manner as Holbein, Kratzer's talents obtained him a court position as astronomer and clock maker to the king.

Sundial by Kratzer, formerly in the garden of Corpus Christi College, Oxford.^[3]

Kratzer also collaborated with Holbein on producing maps, and in return the artist produced a portrait of Kratzer in 1528 that now hangs in the Louvre; it depicts the craftsman surrounded by the tools of his trade, and with an unfinished polyhedral sundial. His close relationship with Holbein and More also may be observed in his annotations of Holbein's draft for his portrait of the More family.^[4] Kratzer identifies the various family members and their ages for the benefit of More's friend, the theologian Erasmus.

Kratzer (under the name Nich. Cratcherus) is recorded as a reader of Corpus Christi College, Oxford, where he is presumed to have taught mathematics.^[3] He designed at least two fixed sundials in Oxford, neither of which now exist. One was in St Mary's churchyard,^[5] the other in the garden of Corpus Christi.^[3] He also designed a portable dial for Cardinal Wolsey, which is now in the History of Science Museum, Oxford.^[6] Another dial attributed to Kratzer was found at Acton Court, near Bristol, in the 1980s.^[7][8]

Peter Drinkwater has presented a critical evaluation of the sundials attributed to Kratzer, in particular the one in the Holbein portrait.^[9] He comments that "Kratzer triumphed, not through genius or creativity, but through having learned what others had discovered and invented, and by being the first to apply that learning in England". John North concurs: "Kratzer doubtless had nothing new to offer of a fundamental kind. Many of his dials were unusual, but his favorite polyhedral dial was perhaps more useful as a repository of verses [...] than for actually announcing the time with any accuracy". Nonetheless, Kratzer brought useful German skills and knowledge to the English court and was well-regarded over a period of nearly 30 years.^[2]

References

1. "Kratzer, Nicolaus (b. 1486/7, d. after 1550)". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/15808. (Subscription or UK public library membership required.)
2. North, J.D. (1978). "Nicolaus Kratzer – The King's Astronomer". Science and History: Studies in Honour of Edward Rosen (Ossolinium Orbis, 1978). Studia Copernica. pp. 205–234. Reprinted in: North, J.D. (1989). Stars, Minds and Fate. Essays in Ancient and Medieval Cosmology. London: The Hambledon Press. pp. 373–400. ISBN 978-0-907628-94-1.
3. Fowler, Thomas (1893). The History of Corpus Christi College. Oxford Historical Society.. See in particular pp 84–7.
4. BBC News article on Holbein's draft of the More portrait, with Kratzer's annotations
5. File:Loggan Oxonia St Mary's Church, Kratzer's Dial, published 1675.jpg
6. "Polyhedral Dial, by Nicolaus Kratzer?, English, 1518–30". HSM Collections Online. History of Science Museum. Inventory Number 54054.
7. White, G. S. J. (1987). "A stone polyhedral sundial dated 1520, attributed to Nicholas Kratzer and found at Iron Acton Court, near Bristol". Antiquaries Journal. 67.
8. Description of Acton Court with a picture of the stone sundial
9. Drinkwater, Peter (1993). "A cold look at Kratzer's "polyhedral" sundial". BSS Bulletin. 93 (2). British Sundial Society: 8–10, 20.

Further reading

• Feingold, Mordechai (1984). The Mathematician's Apprenticeship: Science, Universities and Society in England 1560–1640. CUP Archive.
• Dekker, Elly; Lippincott, Kristen (1999). "The Scientific Instruments in Holbein's Ambassadors: A Re-Examination". Journal of the Warburg and Courtauld Institutes. 62: 93–125. doi:10.2307/751384. JSTOR 751384.
• Sonderegger, Helmut (2014). "UNEXPECTED ASPECTS OF ANNIVERSARIES or: Early sundials, widely travelled" (PDF). BSS Bulletin. 26 (iii). British Sundial Society: 40–44.