Becoming a Virtuoso Painter: Cornelis Ketel's portrait of Adam Wachendorff and Homo Bulla

Barbara Schoonhoven and Arie Wallert, Rijksmuseum Amsterdam

Making Art in Tudor Britain
Abstracts from Academic Workshops (2007-8)
Funded by the Arts and Humanities Research Council

Cornelis Ketel's Portrait of a Man, on the verso a Putto blowing Bubbles is dated 1574 and known as the earliest piece by Ketel painted in London.[1] The imagery is related to the contemporary tradition in medals: a portrait on one side and an allegorical figure, together with a learned motto, on the other. The tondo is 43 centimetres in diameter and has an engaged gilded frame. The man presented is Adam Wachendorff, Secretary of the Steelyard. The bearded man, dressed in black, is standing beside a desk. In his right hand he has a letter. The left, on which he wears a signet ring, is on his hip. On the desk is a pen, ink, paper and a watch: objects which suggest that administration was of prime importance for this man. Wachendorff's family coat of arms can be seen on the inside lid of the watch on the desk. To the left and right of the head is the text: 'ANO DNI 1574/AETATIS SUAE 35 CK'. Written on the frame is the text 'SERMO DEI AETERNUS CAETERA OMNIA CADUCA'. On the reverse is a putto blowing soap bubbles set against a stormy sky. Above this Homo Bulla is the Greek motto, 'Man is a soap bubble'. Click here to view images.

The Homo Bulla is quite well preserved; the portrait shows more damages and discoloured retouchings. The varnish has yellowed quite severely. The tondo did not undergo conservation treatment, but the Tudor Research Project provided the opportunity to study the painting more carefully.

The panel support is covered with a conventional calcium carbonate / glue ground. This off-white ground is applied with a broad brush; relief is visible following the circular support along the edge. The composition was first sketched in black on the white preparation. A preparatory drawing in a dry material, possibly graphite, is visible in infrared.[2] The lines in general are thin and searching to define the contours. Small changes are made in the position of Wachendorff's arms and hands, and the thumb, holding the letter, was replaced. The letter was made bigger and (partly) painted over the background. The Homo Bulla, landscape and clouds on the reverse are under drawn in thin, searching lines. His proper left arm was originally planned higher and there are many searching lines to define the contours of his legs.

Elemental analyses (ED-XRF) and light microscopy (PLM) provided more information on the paint composition. Several cross-sections were taken to study the build-up of paint layers with microscopy in reflected light (BF) and UV-fluorescence. Three different goldgrounds were used by Ketel to apply the gilding. The gilding on the edge of the frame around the portrait is applied on top of a reddish mordant applied in two layers of slightly different composition, mainly containing earth pigments.

Examination of the inscription over the 'golden' background of the portrait gave unexpected results. First of all the warm golden yellow background turned out to be painted in ­ severely discoloured ­ smalt. The background behind the portrait of Wachendorff, now of a golden yellow tone, was originally blue. The paint layer contains mainly smalt particles with some lead white. The smalt particles appear either pale greyish blue or colourless in cross-section. This smalt appeared to be a particularly potassium-rich cobalt glass. The presence of cobalt, nickel and a trace of arsenic indicates that the cobalt ore to make this glass blue comes from cobaltite