Nicholas Kratzer (b. 1486/7, d. after 1550) was astronomer and astrologer to King Henry VIII. He was also an instrument maker, and is thought to have collaborated with Hans Holbein the Younger (1497/8-1543), one of the most important artists of the 16th century, who included complex instruments in a number of his works. This miniature portrait depicts Kratzer with an armillary sphere; it is one of the earliest known English examples of miniature portraiture.
In previous Whipple Museum catalogues and labels this miniature portrait (Image 1) is described as originating from the "School of Hans Holbein the Younger", and as depicting Nicholas Kratzer. Both Holbein and Kratzer were employed at the court of King Henry VIII, and both brought their expertise - painting and instrument making respectively - to England from the Continent.
The earliest known miniature painted in England dates from around 1525, and is by Lucas Horenbout. Horenbout is thought by some to be the artist who introduced Holbein to miniature painting. The Kratzer miniature bears a strong resemblance to works by Horenbout, and it can be placed with some confidence in the tradition surrounding him, rather than the "School of Hans Holbein".
Dating the Whipple's miniature portrait is more difficult. Holbein painted a full-sized portrait of Kratzer in 1528 (Image 2), when Kratzer was 41. But the Whipple's miniature portrait appears to be of a younger man and may date from around this period, possibly earlier. Of course, given the lack of records relating to the painting, there is no way of verifying that Kratzer was actually the sitter. However, the painting bears a similarity to Horenbout's work, and it is likely that the painting dates to circa 1530.
Update: In August 2014 the historian of art Lindsey Cox visited the Whipple Museum to study the Kratzer portrait. Cox, a specialist in portrait miniatures, has written a blog post about her research, which raises further questions about the painting. Can it be attributed to the schools of either Holbein or Horenbout? Is the person depicted really Nicholas Kratzer? Might the miniature in fact have been painted in the eighteenth, rather than the sixteenth, century? Seventy-nine years after Robert Whipple purchased this painting, many questions still remain about its true identity.
A sale catalogue of 1935 describes the portrait:
"Nearly profile to the right, in brown fur cloak over a black doublet, with white lawn collar, and black felt hat; a gold chain around his neck. In his left hand he holds a brass armillary sphere; blue background."
The armillary sphere is a common object in depictions of astronomers; it has long been a symbol of learning. But unlike the instruments painted in Holbein's portrait, the armillary sphere in the miniature is crudely drawn. This is often the case with portrayals of a complex instrument, but it is unusual given Kratzer's employment as an instrument maker and his probable involvement with Holbein's other paintings featuring instruments. Again the identification of Kratzer, or at least his involvement with the painting, comes into question.
In the collections of the Whipple Museum, the armillary sphere accompanies images of Nicholas Copernicus, Isaac Newton, Nicholas Saunderson, and appears on a trade card of the instrument makers Heath and Wing dated circa 1740. Perhaps the most unusual use of an armillary sphere in the arts is Umberto Eco's description of a gruesome murder with the instrument in his novel The Name of the Rose:
"An archer picked the armillary sphere up from the floor and handed it to Bernard. The elegant architecture of brass and silver circles, held together by a stronger frame of bronze rings grasped by the stem of the tripod, had been brought down heavily on the victim's skull, and at the impact many of the finer circles had shattered or bent to one side."
Boris Jardine, 'A miniature portrait of Nicholas Kratzer, the King's astronomer', Explore Whipple Collections, Whipple Museum of the History of Science, University of Cambridge, 2017 [http://www.hps.cam.ac.uk/whipple/explore/astronomy/thekingsastronomer/, accessed 27 March 2017]