Jan Veth's paintings of Jacobus Kapteyn

Jacobus C. Kapteyn was one of the most prominent astronomers worldwide in the beginning of the twentieth century and is nowadays regarded as one of the coryfees of the University of Groningen. His legacy is not only the prominence of Dutch astronomy during the twentieth century through his students like Jan Oort and Willem de Sitter and the Dutch school that followed. Part of his legacy is also the two paintings of him, produced in oil on canvas by prominent Dutch painter Jan Pieter Veth. One, showing him working at his desk, decorates the Kapteyn Room in the Kapteyn Astronomical Institute together with a painting of Mrs. Kapteyn by a different artist, and the other one, displaying Kapteyn in academic attire, is part of the University of Groningen’s gallery of professors in the Senate Chamber of the central Academy Building. The first was offered to Kapteyn and his wife on his 40th anniversary as Professor in 1918 and the second to the University after his retirement in 1921. There has been some confusion about the way in which these paintings have been produced, to the extent that it has been suggested that there must have been a third portrait that now is lost. Former Director of the Kapteyn Astronomical Institute Adriaan Blaauw has proposed that the one in the Senate Chamber actually is a first version meant to be offered to Mrs. Kapteyn in 1918, but at her request replaced by the one now in the Kapteyn Room. The first version was then later adapted to the requirements of the gallery of professors by Veth himself by overpainting it with academic gown, jabot and beret. A preliminary trial version in oil on wood by Veth, in the possession of Kapteyn’s namesake and greatgrandson Jack Kapteyn, shows what this painting would have looked like before the adaption by Veth. Recently an exhibition of Veth’s work (including the two Kapteyn paintings) was held in the Dordrechts Museum, in Veth’s city of birth, where it was stated as a fact that three paintings were produced of which one now is lost. The following reports on a critical evaluation of the available evidence, including the biography of Jan Veth that well-known historian Johan Huizinga, friend of Veth, wrote not long after the latter’s demise, and letters Veth wrote to his wife while he was working on these paintings in Groningen. I conclude that the evidence provides strong support of Blaauw’s proposed sequence of events with a few modifications, and that no third, now lost, painting has been produced. For those readers less familiar with Kapteyn, or those that want to read more background on Jan Veth or wishes to read more extended parts of transcripts of Veth’s letters, a much longer version in manuscript form of this paper is available as van der Kruit (2024).