Rocznik Muzeum Narodowego w Warszawie (3(39).2014)

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Attribution and Technological Research on Old Master Paintings and Drawings

more flexible and to serve as adhesive between them and the secondary support. Next, the
canvas was put on the back of the paint layers and intense pressure was applied to obtain
better adhesion of the binding agent. This resulted in a partial overflow on the edges of the
canvas. Afterwards the painting was wound onto the final stretcher and gaps in the paint were
filled, sometimes excessively, as in the blue of the sky that also appeared on the fringes of the
canvas. These fringes were eventually unified in colour with the use of light grey paint. The
outer canvas (gauze) visible on the Boston version could have been added when the preceding
canvas had been damaged on the edges of the stretcher.
The method of transfer and the materials used indicate that it may have taken place in
the 18th century. In order to confirm this, further physicochemical investigation ought to be
undertaken; above all, vehicles of particular layers should be analysed (no such examination
of either painting was executed).
To sum up, the arguments to support the thesis that the Boston version has been transferred
from panel onto canvas are:
- presence ofcracks in the technological layers which are typical only of wood;
- interference of cracks that would occur only upon transfer, caused by wooden support
and generated by canvas support;
- traces of xylophagous insects’ destructive influence on the wood observable in diffused
lighting, and in X-ray and IRR images;
- a horizontal crack in the paint layers (through the figure of Saint Joseph and the ba-
ckground), frequently occurring during transfer;
- absence of ground in the concavities of the weaves of the canvas on the surface of the
painting, on its edges and fringes;
- neither the stratigraphic examination nor physicochemical analysis of the painting
materials revealed any traces of gypsum ground, which would be typical of Italian
painting at this time;
- the composition of the layer directly underneath the paint layers matches the substan-
ces used for transfers (transfer mass).
EPP, IMS
X-ray Fluorescence Spectroscopy (XRF) Examination
Comparative analysis of the painting materials was used to determine whether or not both
versions of The Holy Family were executed simultaneously in the same studio.
In order to identify painting materials a non-invasive and non-destructive analytical method
was used: X-ray fluorescence spectroscopy (XRF).17The examination is carried out directly on
the object and does not require collecting or preparing samples. Data obtained through interac-
tion of X-rays with a specific area of the object allow for identifying the chemical elements in it.18
17 Barbara H. Stuart, Analytical Techniques in Materials Conservation (Chichester, 2007), pp. 234-38; Krystian
Książek et al., Skarb średniowieczny z Głogowa: analizy specjalistyczne i konserwacja wybranych zabytków / Medieval
hoardfrom Głogów: specialist analyses and conservation of selected objects, Borys Paszkiewicz, scientific ed. (Głogów,
2013), p. 9; Koen Janssens et al., “Recent trends in quantitative aspects of microscopic X-ray fluorescence analysis,
Trends in Analytical Chemistry, vol. 29, no. 6 (2010), pp. 464-78.
18 The XRF examination of the paintings provides information about the chemical elements in both the
upper paint layers and in the ground. During the examination no helium was used that would have made it possible