Nicholas Kratzer, born in Munich in 1487, was a friend of Hans Holbein. In fact, Kratzer’s was one of the first portraits that Holbein painted when he came first to England. But who was Kratzer?
He was a mathematician and astronomer who invented the polyhedral sundial. He arrived in England in 1516 from Cologne to teach mathematics at Corpus Christi College, Oxford. He was about thirty at the time. He went on to be employed by Henry VIII as Court Astronomer in 1520 to make clocks and sundials. The clock at Hampton Court is is work. Wolsey also gave commissions to Kratzer for similar items. Both men were demonstrating that they were renaissance men. It wasn’t enough to know languages (both ancient and modern) it was also essential to be seen as a man of science. Inevitably Henry’s courtiers also sought out Kratzer to demonstrate their own learning and to keep up with the Tudors and their cronies. One of Kratzer’s sundials was uncovered at Iron Acton Court near Bristol which is now in the hands of English Heritage but once belonged to Nicholas Poyntz – demonstrating that the trend for horology spread far beyond the court setting.
Kratzer moved in the England’s leading intellectual circles. He tutored Sir Thomas More’s children and this was where Holbein seems to have first met him. More writes of Kratzer in a letter to his family:
But I think you have no longer any need of Master Nicholas [Kratzer], since you have learned whatever he had to teach you about astronomy. I hear you are so far advanced in that science that you can not only point out the polar star or the dog star, or any of the ordinary stars, but are able also…to distinguish the sun from the moon! Onward then in that new and admirable science by which you ascend to the stars!
Holbein’s original portrait of Sir Thomas More’s family no longer survives but the original sketch which was presented to Erasmus as a gift by More is still in existence. Each member of the family is carefully annotated in a hand that is not Holbein’s – it is Kratzer who not only knew More, Erasmus and Holbein but also Durer who wrote that Kratzer has provided invaluable assistance in technical matters. Kratzer also knew Thomas Cromwell who was an astute man of business with many German links.
Kratzer provided Holbein with technical information. Experts believe that the mathematical instruments and dials depicted in Holbein’s The Ambassadors were provided by Kratzer. The men worked together for the décor of the Banqueting House at Greenwich in 1527. It was a temporary building designed to allow the king to show off his wealth, splendor and just how learned he was – iconography was incredibly important in the sixteenth century so Kratzer’s advice was essential. They collaborated in the making of maps.
It is interesting to note that his death is written as circa 1550 and even his birth is based on guesswork derived from how old he looks in Holbein’s portrait which was painted in 1528. The painting in the National Portrait Gallery is not Holbein’s original, that hangs in The Louvre.