The RKD – Netherlands Institute for Art History (The Hague) – and CATS – Centre for Art Technological Studies and Conservation (SMK, Copenhagen) – end of last year launched a new wood research platform, Dendro4Art.
This new research tool provides unique dendrochronological research data on panel paintings and wooden sculptures around the world. This platform will therefore become a global hub for dendrochronologists and art historians, giving them access to extensive research data that includes raw data as well as information about dendrochronology. The platform explicitly invites users to share data themselves, helping to further strengthen the research community.
Dendrochronology is the study of wooden objects, such as panel paintings, which focuses on the width of the annual growth rings in the wood. Climate conditions determines the width of each annual growth ring throughout the lifetime of a tree, resulting in unique variations in the widths of the growth rings specific to each time period and types of wood. Dendrochronologists compare these tree ring patterns, or measurement series, with growth ring chronologies from thousands of trees. In doing so, they are able to establish the precise geographical origins of wooden objects, as well as to date them.
In April 2019, the RKD presented dendrochronological reports and work drawings drafted by Em. Prof. Dr. Peter Klein (University of Hamburg) online. At that time, the research community expressed a strong desire to also consult the raw data from the dendrochronological research – data that can also be used for further research by other scholars. Now, vast amounts of raw data, also known as measurement series, provided by Professor Klein and colleagues will be publicly available thanks to the collaboration between the RKD and CATS.
All this dendrochronological data can be freely downloaded via the Dendro4Art portal. It provides a platform for scholars to share information about dendrochronology and remain up to date on the subject, and also enables interested parties to learn more about dendrochronology. The hub is linked to the RKD’s (Netherlands Institute for Art History) databases. The RKD technical database contains vast volumes of dendrochronological research data, while RKDimages provides a wealth of art historical information on paintings studied. All these databases also provide links to information about the artists, archival information, and further research documentation.
This wealth of data at the heart of the RKD ensures that the dendrochronological data is safeguarded within a durable infrastructure. RKD and CATS therefore explicitly invite researchers to share their data via the Dendro4Art platform with the aim of providing a dynamic and ever-growing dendro-network. This data can again be correlated to data on artists and their whereabouts, marks on their panels issued by a panel maker, X-radiographs and many other analytical techniques.
The Dendro4Art project was made possible thanks to generous funds provided by the Danish Carlsberg Foundation.
In 1994, after an interview on the progress of restoring Vermeer’s Girl with a Pearl Earring, a Dutch newspaper proclaimed that ‘Jørgen Wadum is in love with her’. Although never so candidly declared from my side, it should be noted that our relationship started much earlier. It may appear predestined, but in the 1960s during my teen-age years in Vejle (Jutland, Denmark), I had an A1-size poster of the Girl prominently displayed on the wall in my room. So, the Girl and I are in fact beyond a ‘golden wedding anniversary’. Like in any good relationship, the Girl continues to enchant, inspire, and fascinate.
Thanks to the recent Girl in the Spotlight project, all the notes, letters, drawings and thoughts encountered during my first face-to-face meeting with the Girl in the 1990s were again brought to light. It was a bit like rediscovering a box in the attic with relics from the past.
Having a new team of internationally acclaimed experts review the documentation from the 1994 Vermeer Illuminated project – deliberations, photographs, and the research results compiled by the team of experts from the collaborating disciplines within conservation, conservation science, and art – could appear nerve-wracking. It was, however, a delight to learn that the painting is still in good condition. The removal of a brown ‘gallery tone’ of deliberately tinted varnish (applied after the 1960 restoration) and the delicate inpainting by Nicola Costaras in 1994 has survived the test of time.
Therefore, it has been a thrill to witness how the fresh approach by the Girl in the Spotlight project team and their highly sophisticated equipment evaluated the material composition of Vermeer’s painting anew. Advancing our understanding of the artist creative process will teach us to better understand his intention with the painting.
Creating a painting means making material choices. A variety of different brushes would move the paint from the artist’s palette to the canvas. The pigments bound in oils would be layered to indicate or mimic the textures of textiles, skin, and the moisture on her lips and in her eyes. Standing in front of the painting in the Mauritshuis offers the beholder a unique experience of privacy – the Girl and you captured by her enigmatic gaze – and one becomes engaged in a very secret and emotional conversation.
Unravelling the meaning of making of a painting teaches not only researchers and caretakers of these delicate art works how to best understand and care for them for the enjoyment of future generations. We come to understand past interactions between a variety of traders of materials and pigments. From Afghanistan to Latin America they came and became mixed with locally produced white pigments and yellow colourants. They all landed in the paint box of Vermeer. In Delft. The world was at his fingertips.
The Girl with the Pearl Earring was created by stuff from around the globe, and the current top-notch international science project has nuanced and elucidated this further. The Girl herself is always up for a dialogue with everyone in the world.
Online zoomable image of Girl with a Pearl Earring: http://www.micro-pano.com/pearl/.Images made using the Hirox 3D digital microscope at 35x magnification (4.4 µm/pixel), and details at 140x magnification (1.1 µm/pixel)
Vincent van Gogh’s recent birthday on March 30 (1853-1890) made me recall one of my first hands-on encounters with a van Gogh painting after arriving in The Netherlands in 1990. It was his wonderful spring-painting with Pink Peach Treesin Blossom, also known as Souvenier de Mauve. Painted in Arles at the end of March 1888, the delicate pink flowers of the tree that emerged almost directly after the snow had melted, signalised almost a rebirth of life itself.
However, the joy soon became overshadowed by a letter he received from his sister telling him that his cousin Anton Mauve (1838-1888), a prominent painter of the Hague School, had died. Mauve had taught Vincent to paint and he therefore decided to dedicate the Pink Peach Trees to Mauve.
The painting was made in the open air, as Vincent wrote to Theo, ‘… in an orchard — ploughed lilac field, a reed fence — two pink peach trees against a glorious blue and white sky. Probably the best landscape I’ve done. Just as I brought it home I received from our sister a piece in Dutch dedicated to Mauve’s memory, with his portrait (really good, the portrait), the text poor and saying nothing — pretty etching. But something or other grabbed hold of me and made my throat tight with emotion, and I wrote on my painting
and if you think it’s good as it stands we’ll send it to Mrs Mauve in both our names.’
In preparation for the 1990 centennial van Gogh exhibition, organised in tandem by the Van Gogh Museum and the Kröller-Müller Museum, the painting with the Pink Peach Trees needed conservation/restoration. Although in a physically stable condition, the image was marred by thick layers, even lumps, of yellowed beeswax from an earlier lining. Also fragments of the brown paper used for the facing and remains of starch-glue were stuck between the ridges of the pastose paint that Vincent had energetically applied. The aesthetics of the painting did not offer a just representation of van Gogh’s spring impression a little more than a hundred years earlier.
The removal of excessive wax, starch and paper remains on the surface of the paint was quite laborious and lasted a considerable number of weeks. Therefore, based as I was at the Mauritshuis in The Hague, I during the early months of 1990 on Monday mornings travelled to Otterlo and stayed at the local Hotel Jagersrust for three days each week. Apart from getting more than acquainted with the menu – whatever plate, the chef would always spice it with Muscat – it was a great pleasure to travel through the national park De Hoge Veluwe each morning to the gorgeously positioned Kröller-Müller Museum. Here I bent over the microscope in order to carefully clean every single cavity and ridge of paint over the entire surface of van Gogh’s painting.
In connection with preparations for upcoming exhibitions, many of van Gogh’s paintings in other museums were examined for their material composition. It became evident that several of the pigments used by the painter were not light-stable and in some cases the colours had faded to a degree that nowadays we get a distorted impression of the painter’s elaborate palette. Still sophisticated scientific studies continue to improve our understanding of the materiality of van Gogh’s paintings, helping to understand their current state and to determine appropriate strategies for preservation and display.
After the cleaning of van Gogh’s Pink Peach Trees at the Kröller-Müller Museum, the contrast between the pink blossoms and the blue sky was largely recovered – although some fading of the colours had occurred. In several cases, through the microscope, in tiny craquelures of the faintly pink blossoms, one could observe a much stronger pink colour within the core of the paint. An autograph repetition of the Peach Trees, now in the van Gogh Museum in Amsterdam, unfortunately displays flowers that are now virtually white, although these peach blossoms too were originally vivid pink.
Thanks to Vincent’s letters we know much about the pigments, or rather the tube colours, he ordered from his brother Theo in Paris. It may be valuable to recall that the notion ‘tube paint’ was quite new at the time. Invented in 1841 by the portrait painter John Goffe Rand (1801–1873), who lived and worked in Boston, London, and New York, the tube paint only became commercially available during the second half of the 19th century. Van Gogh mentions tube paint for the first time in a letter in 1882. Strong competition on the market of paint supplies could lead to experiments in paint production whereby extenders were added, and the quality of binding media was compromised in order to boost the retailer’s profit.
As mentioned, at the end of February or early March 1888, following the announcement of the death of Anton Mauve Vincent had contemplated sending the widow, Jet Mauve-Carbentus, a painting in memory of her late husband. The plans advanced slowly, but at the end of March he took action and reportedly chose his best painting, the Pink Peach Trees, and fitted it with the inscription: Souvenier de Mauve, Vincent & Theo. He wrote to his brother Theo that, when the painting was dry enough to transport, he would send it to The Hague via Paris. This happened in early May.
You may have noticed that on the painting we see the dedication and Vincent’s own name painted in a dark carmine. But contrary to what Vincent wrote to Theo, as quoted above, we do not see the continuation of the inscription, which should read ‘& Theo’.
We should realize that Theo was not only strongly connected to his older brother in a personal sense, but also continuously promoted Vincent’s paintings, trying in every way to gain recognition for his work among art circles in Paris and in The Hague . We may understand that the idea of sending Souvenier de Mauve to Mauve’s widow was born not only out of compassion for her situation , but also in the hope that the influential Hague art dealer Hermanus Tersteeg (1845-1927) would eventually see the painting.
The explanation for Theo’s name missing on the painting seemed ambiguous at first. Did Vincent write in his letters about an intention that was never carried out? Or would Vincent himself later remove Theo’s name – maybe inspired by his brother? Neither of these hypotheses were unanimously embraced during discussions in the nineteen-nineties, and none of my predecessors, who had treated the painting in the past, had detected any evidence of tampering with the inscription that could support the latter scenario. Vincent, it was thought, must therefore have been mistaken – or never have executed the entire inscription – as intended in his letter – or – could it be that it was not Vincent who removed Theo’s name before the paint had dried?
Well, having studied the paint layer meticulously under the stereomicroscope, an argument arose. Under high magnification, one could detect miniscule traces of carmine within the paint structure in the area right after Vincent’s name where the inscription ‘& Theo’ was allegedly painted. Further one could observe some minute wear of the surface that was smoothened to a degree that no pastocity in the paint was left – as if a very finely woven cloth had been rubbed over the surface leaving traces of microscopic grooves in the surface. On a microscopic scale it almost looked comparable to car-tyres skidding over an almost dry clay ground.
Would this indeed indicate that the last part of the signature could have been removed after a little more than a month when the painting was shipped to Theo in Paris? The possibility that the removal could have been done by Theo, as a gesture to Vincent and in order to promote him, rather than Vincent himself playing any part in this matter, may be further substantiated. We must recall a letter to Theo where Vincent complains, that “…This zinc white that I’m using now doesn’t dry. If everything was dry I’d send a consignment at once.”
I therefore put forward the following explanation of the missing name: After the news of Mauve’s death, Vincent takes his newly painted image of the Pink Peach Trees and signs it in full in dark carmine paint ‘Souvenier de Mauve, Vincent & Theo’. In May when the painting arrived by Theo he, thanks to the slow drying zinc white paint below the carmine paint of the inscription, could carefully wipe his own name away – almost without a trace. A token of dedication that fully underscores Theo’s fullhearted support to his older brother in his struggle to be recognised by The Hague cultural elite.
As far as Van Gogh’s painting of the Pink peach trees is concerned, it is amusing to recall that the Danish painter Christian Vilhelm Mourier-Petersen (1858-1945), who art Van Gogh did not hold in very high esteem, painted almost exactly the same motif. Mourier-Petersen went to Arles from around 10 October 1887 to 22 May 1888 – apart from a brief stay in Martigues at the end of March 1888. It was in mid-March 1888 that Mourier-Petersen and his colleague Dodge MacKnight (1860-1950) met Vincent in Arles. From correspondence we know that Mourier-Petersen and Van Gogh met each other frequently and we may assume that Mourier-Petersen’s painting of the luminous light peach trees is painted while standing side by side with Van Gogh.
Vincent writes, “I’ve made the acquaintance of a Danish artist… What he does is dry but very conscientious, and he’s still young”. From his side Mourier-Petersen wrote about Vincent , a few days after their first meeting,: “Initially I considered him to be mad, but by and by I note that there is method in it.” In spite of their differences, they enjoyed each other’s company and in his letters to Theo, Vincent mentions the Danish artist several times with affection.
Mourier-Petersen left Arles and set off for Paris and Vincent persuaded Theo to allow his Danish friend to stay with him in the Rue Lepic, where Mourier-Petersen arrived on 6 June 1888. Before he left, he must have seen Vincent’s full dedication on the Pink Peach Trees – including Theo’s name.
One hundred years later, in 1990, another Dane after hours of peering through a stereomicroscope unravelled evidence of where the full inscription in carmine was once situated – and the ever so faint traces of how it was rubbed away from the almost dry paint some time after its application.
 Oil on canvas, 73 × 60 cm. Kröller-Müller Museum, Otterlo, inv. KM 108.317.
 Anton Mauve died on 5 February. Around 30 March, in response to his death, Van Gogh painted Pink Peach Trees (‘Souvenir de Mauve’) and decided to give it to Mauve’s widow, Jet Mauve-Carbentus. See letter 590. All references to letters are from: Leo Jansen, Hans Luijten, Nienke Bakker (eds.) (2009), Vincent van Gogh – The Letters: http://vangoghletters.org/vg/
 For recent studies see: Ella Hendriks & Marije Vellekoop (eds.), “Van Gogh’s Sunflowers Illuminated: Art Meets Science”, in Van Gogh Museum Studies, (Amsterdam University Press/Van Gogh Museum, Amsterdam, 2019). For van Gogh’s palette see: M. Geldof, A.N. Proaño Gaibor, F. Ligterink et al. “Reconstructing Van Gogh’s palette to determine the optical characteristics of his paints”, in Herit Sci 6,17 (2018). https://doi.org/10.1186/s40494-018-0181-6. On the consequences of colour change for conservation of Van Gogh’s works, see: Ella Hendriks, “’Paintings fade like flowers’: consequences of colour change in paintings by Vincent van Gogh”, in Proceedings of the ICON paintings group conference, Appearances and Reality: Examining Colour Change in Paintings, Tate Britain, 9 October 2015 (Archetype, London, 2016), pp. 39-51. I am grateful to Ella Hendriks for references and a critical review of my text.
 See part II “Van Gogh’s Triptych of Orchards in Blossom”, in Cornelia Peres, Michael Hoyle and Louis van Tilborgh (eds.), “Technical and Art-Historical Studies on Works by Van Gogh and Gaguin”, A Closer Look, Cahier Vincent 3 (Waanders, Zwolle,1991).
 See cat. Otterlo 2003, The paintings of Vincent van Gogh in the collection of the Kröller-Müller Museum, by Jos ten Berge et al., pp. 212-213.
 In letter 591 to Theo van Gogh. Arles, on or about Sunday, 1 April 1888.
 Vincent suggest this possibility in relation to another dedication on a painting meant for Tersteeg, where he wrote to Theo, that “…you can scrape off the dedication“. Letter 608, Arles, Thursday, 10 May 1888
Peach Trees in Blossom. Arles, 1888. Oil on canvas, 55,2 × 45 cm. The Hirschsprung Collection, inv. nr. 407.
 In letter 584 to Theo van Gogh. Arles, Saturday, 10 March 1888.
 H. Larsson, Flames from the south. The introduction of Vincent van Gogh in Sweden before 1900. Thesis. Lund 1993, pp. 14, 26.
The world only has few paintings by “Un celebre Peijntre nommé Verme[e]r”, the Delft artist Johannes Vermeer (1632-1675). Pending on scholarly judgements, just 35 or 36 paintings are preserved, and they are all on display in public museums. Based on his professional career that spanned only twenty-two years, a qualified estimate of Vermeer’s complete oeuvre reaches no more than forty works. He left no drawings or preliminary paintings behind.
Archival research and provenance studies are still ongoing in order to understand more about the life and work of Johannes Vermeer. Naturally, an attribution’s authenticity is significantly strengthened if direct links over time to the artist himself can be established. Equally so if an ownership during the artist’s lifetime or soon after his death can be proven.
In the past it was imagined that Vermeer after his untimely death in 1675 was soon forgotten and appeared relatively unknown during the 18th and early 19th centuries until rediscovered by Thoré-Bürger (1807-1869) in 1866 in his article “Van der Meer de Delft” as the ‘sphinx of Delft’. However, research has established that both in his own days and ever since there was a marked for the eloquent painter of first history pieces and later more quiet interior scenes with mundane activities. Private collectors in Delft, The Hague, and Amsterdam possessed his works.
Sometimes Vermeer’s works drew attention under wrong attributions, and in 1742 the Elector of Saxony acquired the Girl Reading at an Open Window as a Rembrandt.The Music Lesson, now in the Queens collection in London, was acquired as a Frans van Mieris (1635-1681) in 1762. Art dealers in Paris praised Vermeer’s works early in the 19th century and he was traded as a pupil or follower of Gabriël Metsu (1629-1667) as well as of Pieter de Hooch (1629-1684). In the late 19th and early 20th century collectors and museums acquired Vermeer’s works as they became discovered and correctly attributed to the Delft painter, who signed less than half of his works and only dated one.
No Danish museum has a painting attributed to or by Vermeer in their collections, however, this could have been different. In 1919 the director of Statens Museum for Kunst, Karl Madsen (1855-1938) had engaged with a Swedish art collector to display his paintings within the museum. It appeared that several of the works were for sale, which caused a rouw in the news press. It offended museum directors and the public opinion and in the journal Social-Demokraten one could read: “…and now the story goes that a Dutch art dealer, who stayed in Copenhagen recently, has given voice of a deal with the [SMK] Director who has offered him space in the Museum, where he intends to open his Shop in the Hammershøi-Gallery!”.
The director proceeded with his plans and in January-February 1920 a collection of old master paintings from the Jewish Dutch art dealer Jacques Goudstikker (1897-1940) from Amsterdam was on display at SMK, the National Gallery in Copenhagen. Among the paintings were works by Frans Hals and Rembrandt, however the highlight was Vermeer’s Young Girl with a Flute, a small panel measuring only 20 × 17,8 cm.
What is noteworthy is that, despite the exhibition catalogue being praised for its beauty, Vermeer’s painting was not mentioned, nor illustrated in the catalogue listing the 65 works on show. Was it added as an extra painting ex-catalogue? Was it important for its provenance having it listed as exhibited at the Danish National Gallery? Today this exhibition is not listed anywhere in the literature on the painting.
Madsen did not hide the fact that the Goudstikker collection was for sale, and he even openly declared his hope that a patron would offer the museum to acquire not only the work by Vermeer, but also works by Van Dyck, Jan Steen, and Frans Hals – unfortunately his aspirations were in vain. Maybe the price of 325.000 guilders was simply too much [today app. € 2 million]. Otherwise SMK now would have had Vermeer’s Girl with a Flute on permanent display – and not merely on a brief visit in 1920, a visit that does not figure in the exhibition history of the painting.
Reviewing the provenance history of the painting, it has been established that it was once part of the Pieter van Ruijven collection in Delft. Later in 1696 it was on sale in Amsterdam. It went to ‘s-Hertogenbosch and from 1876-1911 it went to Brussels. Briefly it was in Paris in 1911. Augustus Janssen in Amsterdam possessed the painting 1919-1921. Apparently commissioned to Goudstikker, the Girl with a Flute already in 1919 was part of the exhibition La Collection Goudstikker d’Amsterdam in the Pulchri Studio in The Hague, as cat.no. 131 with an illustration. It was shortly after that the prolific art dealer Goudstikker had it on show at SMK in Copenhagen in 1920 ex-catalogue.
During the exhibition at SMK, a newspaper prints a picture of Vermeer’s Young Girl with a Flute with the text that the most precious painting in the exhibition is the one by Vermeer. The review concludes that “It would indeed be a national achievement if one of our art-loving tycoons would secure our Gallery with such an artwork”.
During the exhibition at SMK the following assessment of the painting was published: “The costliest portrait in the exhibition is no doubt Johannes Vermeer van Delft’s young ‘Girl with the Flute’. Although the painting has not gone unharmed through life, it is characteristic of the master. It has, to its fullest extent, this extraordinary, opulent atmosphere which characterizes his art. And its colours show his characteristic, saturated harmony. The basic tone is achieved by the young girl’s blue-grey coat, and it is emphasized by her Chinese-like hat, in which various coloured stripes – brown, yellowish, and white tones – are the most prominent. However, the best in shape and colour is the young girl’s left arm and hand. In the rendering of both soft and prominent contours, in the perception of the softness of the carnation, Vermeer unfolds all his peculiarities. Unfortunately, the perception is harmed in different ways. The colours of the scarf and the white fur coat are heavily yellowed, and a less fortunate restoration of the left upper lip and nose tip seems quite disturbing”.
Later the same year, the Young Girl with a Flute was on show in Stockholm and in Kristiania (Oslo) where the Goudstikker exhibition, equally to the Copenhagen venue, was comprising 65 paintings announced in the Norwegian newspaper Morgenbladet. A Danish newspaper wrote that the very small painting, the size of only three columns in their newspaper, in Norway was for sale for the very high amount of DKK 600.000. It was argued that the painting had a wonderful sense of completion, but also highlighted the fact, as the article continued, that “…only very few paintings by Vermeer are known… and out of these the ‘Lady with the Flute’ is regarded as one of the most famous”.
It appears peculiar that Vermeer’s painting was not included in all of the catalogues at all the venues of the Goudstikker exhibitions, however, in the Rotterdam presentation in May 1920 it was indeed. In the following year, it was again exhibited in a public museum like the SMK, this time on loan to the Alte Pinakothek in Munich. Shortly after it was acquired by M. Knoedler & Co. of New York, who in 1923 sold the painting to Joseph Early Widener (1871-1943). In his private ownership, the YoungGirl with a Flute hung at Lynnewood Hall, a Neoclassical Revival mansion in Pennsylvania. Widener was a wealthy American art collector and, as a founding benefactor of the National Gallery of Art in Washington, he bequeathed the painting in 1942.
It is noteworthy that museum director Karl Madsen’s Dutch counterpart, art historian and former director of the Mauritshuis, Abraham Bredius (1855-1946), who privately had acquired Vermeer’s Allegory of Faith, in 1928 sold it to an American collector for $ 300.000 [today app. € 2.4 million]. The painting had been on loan to the Mauritshuis for almost 25 years, and to the Museum Boijmans Van Beuningen, Rotterdam, for another five. Bredius had acquired the painting in 1899 for less than 700 guilders. Although Bredius allegedly never liked his purchase, which he in 1907 called “a large unpleasant Vermeer”, one cannot help speculate if having the painting exhibited in the Mauritshuis and in the Museum Boijmans Van Beuningen would have boosted its value? Could Goudstikker’s presentation of the Young Girl with a Flute at the Danish National Gallery in 1920 have had such an intention? But why then, wasn’t it in the catalogue? Or did Goudstikker anticipate that Karl Madsen indeed would have been able to convince a benefactor to include the Young Girl with a Flute in the Danish national collection?
* This article is dedicated to the memory of my late colleague Ben Broos (1944-2019), head curator at the Mauritshuis 1986-2001.
 B. Broos, Un celebre Peijntre nommé Verme[e]r, in Johannes Vermeer, exh.cat. National Gallery of Art, Washington D.C./Royal cabinet of Paintings Mauritshuis, The Hague (1995-1996), pp. 47-65.
 W. Bürger (Etienne Joseph Theophile Thore), ‘’Van der Meer de Delft’, in Gazette des Beaux-Arts 21: 297-330, 458-470, 542-575.
 Just to mention the most important, Pieter van Ruijven and his wife Maria Knuijt left 500 guilders, a considerable amount, to Vermeer in their last will and testament. This kind of a bequest is very unusual and testifies a close relationship between Vermeer and Van Ruijven that went beyond the usual of patron-painter. It would seem that in his lifetime, the rich Delft burger had bought a sizable share of Vermeer’s artistic output, most likely, more than half.
 V. Villadsen, Statens Museum for Kunst 1827-1952. Copenhagen 1998, p. 216: ”Og nu hører man, at en Hollandsk kunsthandler, som for nogen tid siden opholdt sig her, har ladet sig forlyde med, at Kunstmuseets Direktør ogsaa har tilsagt ham Lokaler i Museet, hvor han altsaa agter at aabne sin Butik i Hammershøisalen”, Soc-Dem, 11-09-1919.
 This took place only shortly after another show in The Hague the previous year: La Collection Goudstikker d’Amsterdam, Pulchri Studio, no. 131 and ill.
Catalogue de la collection Goudstikker d’Amsterdam exposée dans le Statens Museum for Kunst. Janvier-fevbrier 1920, Harlem/Utrecht. See also V. Villadsen, o.c., ref.s 77, 78, 79.
 “Udstillingens kostbareste Portræt er dog utvivlsomt Johannes Vermeers van Delfts af den unge Pige med Fløjten. Skønt det ikke er gået uskadt gennem Tilværelsen, er det dog særdeles karakteristisk for Mesteren. Det har i fuldt Maal dette underlige, livsfrodige, som særtegner hans Kunst. Og dets Farver danner den for ham egne, mættede Harmoni. Grundtonen anslås her af den unge Piges blågraa Kaabe, og den understreges af hendes kineseragtige Hat, i hvis forskellige farvede Striber brune, gullige og hvide Toner er de mest fremtrædende. Bedst i Form og Farve er dog den unge Piges venstre Arm og Haand. I Gengivelsen af dens baade vege og faste Linier, i Opfattelsen af Karnationens delikate Blødhed udfolder Vermeer sig i hele sin Ejendommelighed. Desværre skæmmes Helheden paa forskellig Vis. Halstørklædet og Pelsværkets hvide Farver er stærkt eftergulnet, og en mindre heldig Restauration af venstre Overlæbe og Næsetip virker ret forstyrrende”, Berlingske Tidende, 5 February 1920, p. 3.
 May 1920: Catalogue de la collection Goudstikker d’Amsterdam exposée dans les localités de la Rotterdamsche Kunstkring, cat.no. 19. with illustration.
 B. Broos, o.c., p. 207 and ref. 30: Algemeen Handelsblad, 20 April 1921, Evening Edition, 3rd section, p. 9: “Het ‘Meisje met de fluit’ van Vermeer uit de verzameling Goudstikker, dat eenigen tijd als bruikleen in de Oude Pinacotheek te München is geweest, werd, naar men ons mededeelt, naar Amerika verkocht.”
Girl with a Flute,c. 1665–1670. Oil on panel, 20 x 17.8 cm. (7 7/8 x 7 in.) National Gallery of Art, Washington D.C. acc. no. 1942.9.98. The painting is currently rejected by Albert Blankert; Arthur K. Wheelock Jr. ascribes it as “attributed to Johannes Vermeer.” Most all other scholars accept it as authentic. See also Cat. Johannes Vermeer (1995-1996), pp. 204-208.
 Johannes Vermeer, Allegory if the Catholic Faith, c. 1670-72. Oil on canvas, 114,3 x 88,9 cm. The Friedsam Collection, Bequest of Michael Friedsam, 1931. The Metropolitan Museum, New York.
Without considerable speculation, it is difficult to understand why someone would deliberately want to scratch away evidence of an Antwerp brand on the reverse of a 17th century panel. This is nevertheless what has happened to an oak panel intended for painting but which at some point became used for a marouflage (a technique for affixing a canvas painting to a rigid support) for a Portrait of a Man, possibly painted by Giulio Campi (1500 – 1572).
A detail of the centre-part of the reverse of the panel reveals later criss-cross scratches labouring to remove completely an Antwerp coat of arms that was branded into the wood. Only small remains of the carbonised timer from the hot iron can be observed. The brand (possibly iron no 3, in use 1618-1626) was a sign of approval of the good quality of the panel made by a member of the Antwerp Guild of St. Luke.
To the right of the scratching one observes a small cloverleaf (turned 90° to the left) stamped into the timber. This small leaf is the acknowledged house-mark used by the Antwerp panel maker Michiel Claessens (active 1590-1637).
Due to the marks we can now safely establish that the oak panel used for the marouflage was produced in Antwerp, more than a thousand kilometres North of the Italian Po Plain where the portrait may have been conceived and painted on a canvas sometime during second half of the 16th century. However, when was the painting marouflaged and did this take place in Italy or in the Netherlands? Why scratch away the Antwerp brand but leave the clover leaf of the panel maker intact?
At the Nationalmuseum in Stockholm further examination of the painting will in due course reveal more about its provenance, materiality and history.
The above painting is, however, not unique in having a removed or obscured Antwerp Brand on the back. Two paintings at the SMK display the same fate – and again without a plausible explanation.
Jan Lievens’ (1607-1674) Self-portrait in Profile is one such. It is signed ‘IL’ in ligature. The painting was copied a number of times by assistants or followers. At least one of these copies seems to have occurred simultaneously with the master’s work painted shortly after his arrival in Antwerp in the mid 1630’s.
During examination, it appeared that Lievens’ autograph version on the back had a white patch of paint applied only at the centre of the panel. The paint seemed to cover-up a now hardly distinguishable monogram by an Antwerp panel maker.
After removal of the overpaint, we could not only validate the monogram as that of Guilliam Gabron (1586-1674), but moreover that he used his second punch (datable 1626-1658) to ‘sign’ this panel. Secondly, also the completely obscured Antwerp Brand (no. 4) emerged under the white paint. This particular brand was in use 1619–1638.
The answer as to why the maker’s mark and the Antwerp Brand were overpainted is hard to imagine. Did this happen in order to avoid confusing any 18th century collector about the attribution to Lievens? Would the presence of the Antwerp brand on the back of the Dutch master’s self-portrait cause confusion?
As mentioned, Lievens’ Self-portrait at the SMK was copied multiple times. One of these, identically signed ‘IL’, appears to have both Gabron’s monogram and the exact identical Antwerp brand on the reverse. In this case, the mark and brand were not painted over. The two panels therefore seem to have been produced by not only the same panel maker but also they were both part of the same batch that were approved and branded in the same session by the assay master of the Guild. Subsequently Lievens executed his Self-portrait – which then was copied by another hand on the twin panel.
The dating of this self-portrait has been debated and it has been suggested that Lievens stayed in Antwerp as soon as 1625-26. As Gabron’s second punch, stamped into the reverse, seems introduced in 1626, Lievens could have brought the two panels with him to Leiden. However, a dendrochronological examination suggests that the panel was available only after 1633. As Lievens between 1632 and 1634 temporarily resided in London, the open question would be if the London art marked would have Antwerp panels ready for painting – just as was the case in Paris?
Another possibility may be that this self-portrait by Lievens – and its copy – may be the earliest evidence we have of Lievens admitting an assistant in his Antwerp studio shortly after his arrival from London. We may even speculate that the assistant could have been the fifteen year old Hans van den Wyngaerde. On the 1st of March 1636, the notary Ghijsberti drafted a contract between Lievens and the young apprentice who was to receive training for the coming six years.
If this suggestion is convincing, we may then assume that Lievens’ Self-portrait and its copy were both painted between March 1636 and sometime in 1638, the year in which the use of the Antwerp brand no. 4 seems to run out of use for branding panels. However, the riddle about why someone in the past tried to erase or obscure the presence of panel makers’ stamps and Antwerp brands on an unpainted panel-backing for an Italian portrait of the 16th century and on a Dutch master’s self-portrait of the 17th century still remains to find a plausible explanation…
 J. van Damme, ‘De Antwerpse tafereelmakers en hun merken. Identificatie en betekenis’, in Jaarboek Koninklijk Museum voor Schone Kunsten, Antwerpen 1990, p. 193-236.
Italienskt Måleri I Nationalmuseum: Marknad, Musealisering, Materialitet / Italian Paintings At The Nationalmuseum: Market, Musealization, And Materiality. Further information on the project will soon be made available on the Nationalmuseum website.
 The painting is mentioned in the Danish Royal Collection, Kunetkammeret, already in 1737. SMK, inv. KMSsp413.
 The portrait is strikingly close to J.G. van Vliet’s etching/engraving after Rembrandt, Bust of a man in a gorget and cap with feather. Signed in the plate RHL. v Rijn. jn. 1631. JG v. vliet fecit. Amsterdam, Rijksmuseum, inv. nr. PK-P-OB-33.369. An almost identical painting in reverse show a Profile of a man with feathered cap and long wavy hair. Monogrammed lower left RHL. Oil on panel, 23.8 x 18 cm. Germany, private collection. See more here: http://www.garyschwartzarthistorian.nl/323-the-r-k-czy-identity/.
 Jørgen Wadum, ‘The Antwerp Brand on Paintings on Panels’, in Looking Through Paintings, ed. E. Hermens, 11, pp. 179-198. Archetype Publications Ltd., 1998, p. 186, fig. 8, as brand no. 4.
 A cradled copy on panel, 51,2 × 37.8 cm, is in Weimar (Thüringen), Schlossmuseum Weimar, inv./cat. no. G 59.
 Sale Christie’s Amsterdam, 9 May 2000, lot 87, as from a private collection in Stuttgart. The painting is known to the author and currently in a private collection.
 B. Schnackenburg in cat. The Mystery of the Young Rembrandt, by E. van de Wetering & B. Schnackenburg et al., Staatlische Museen Kassel, Gemäldegalerie Alte Meister & Museum Rembrandthuis, Amsterdam, 2001-02, p. 111. See also L. Bøgh Rønberg in cat. Rembrandt? The Master and his Workshop, by L. Bøgh Rønberg et al., SMK, 2006, pp, 212-213.
 A. Koopstra, ‘De Antwerpse ‘witter ende paneelmaker’ Melchior de Bout (werkzaam 1625/26-1658): leverancier van ‘ready-made’ panelen voor de Parijse markt’, in Oud Holland, Vol. 123, nr. 2 (2010), pp. 108-124. DOI: https://doi.org/10.1163/003067212X13397495480826
 For Hans van den Wyngaerde, see: K. de Clippel, ‘Adriaen Brouwer, portrait painter: new identifications and an iconographic novelty’, Simiolus, vol. 30 (2003), pp. 199-200. https://www.jstor.org/stable/3780916?seq=1. I am grateful to Piet Bakker for this reference.