The IRR and XRR images recorded for La toile de Pénélope, (Fig. 1) revealed straightaway the presence of two woman’s feet beneath the visible portrait. The discovered feet and the way they are displayed, undeniably appear connected to L’évidence éternelle, a truncated female nude composed of five separate small canvases, Magritte first painted early on his career (\(\hbox {RMCR n}^\circ \,327\) [10]) and reproduced twice afterwards (Fig. 2).
The prototype executed in 1930, possibly inspired by Salvador Dali’s portraits enclosed in human body shapes, shows a truncated nude of Georgette Magritte, painted in a three-quarter view (Fig. 2a) [10]. In 1948, Magritte completed another version of the work in which the model (still not identified) is portrayed in a frontal view (Fig. 2b) [11]. We know from Sylvester that a third and last variant of L’évidence éternelle was attempted by Magritte in 1954 [4]. However, the entire completion of this late version remained uncertain since, until recently, only three canvases have been traced (Fig. 2c): the face, the breast and the knees. The canvas of the face corresponds to a small woman’s portrait subsequently titled La ressemblance, and stayed with Magritte until his death (Fig. 3a). Unfortunately, its model, a young blond woman had not been identified. The artist offered the canvas of the breast and the one of the knees to Suzi Gablik, a young American author who lived with the Magrittes for eight months in 1960 [12]. Gablik kept the canvas of the knees and sold the one of the breast to Robert Rauschenberg [4].
The subject and the framing of the picture found beneath La toile de Pénélope, but equally its size leave little doubt about its provenance. Like the face, the breast and the knees belonging to the 1954 variant, the discovered feet are represented in a frontal view. Moreover, the canvas dimensions (24.6 × 14.8 cm) perfectly match with the stretcher format ascribed to the feet part (25 × 15 cm) in the project draft of L’évidence éternelle from 1954 (Fig. 3b) [4].
The underlying purple layer, punctually visible on the right edge of the painting (Fig. 4a), can be reasonably considered as the background color behind the feet. Indeed, the observed purple color perfectly tones with the background color found in the part of the knees (Fig. 4b). In the light of this outcome, the purple signature affixed in the upper right corner of La toile de Pénélope (Fig. 5a) can be seen as a deliberate reminiscence of the sacrificed picture.
The examination of the painting surface with raking light unveiled Magritte’s signature from the lost picture in the lower left corner (Fig. 5b). Although the third canvas that should contain the navel is still missing, the discovery of the fifth part containg a signature strongly indicates that Magritte would have actually painted a navel part as well and that this variant was once a complete set.
The Raman measurements performed on the purple under layer unscathed by the current brown background allowed the identification of Ultramarine, vermilion, lead white and carbon black. In addition, the MA-XRF analysis of the whole painting permitted the identification of inorganic pigments originating from both the visible image and the hidden composition. The distribution maps recorded for Hg and Pb (Fig. 6) support the presence of Vermilion and lead white in the overall background color enclosing the feet. The Hg scan provided further information on the lost image since it made visible the former signature lying just below the left foot as a shadow. Concerning the feet themselves, the MA-XRF scans of the Zn, Fe and Ca elements (Fig. 6) indicate flesh tones based on zinc white and iron oxide/hydroxide pigment(s) with Ca contents.
Like reported for several other Magritte’s oil paintings and observed in MA-XRF scan of the painting side, the present canvas has been primed with two separate ground layers, a first one based on lead white and a second one based on zinc white [2, 13,14,15,16].
The MA-XRF results (Fig. 6) and the Raman spectra related to the visible portrait led to the identification of titanium white (anatase), barite, strontium sulfide, zinc white, vermilion, iron oxides with calcium contents, ivory black and ultramarine. The white pigment predominantly used for painting La toile de Pénélope is titanium white (anatase), associated with barite and strontium sulfide. However, zinc white has been equally identified from the painting surface, chiefly in the flesh tones. Besides titanium white and zinc white, the flesh tones involve iron oxides pigments with calcium contents, vermilion and ultramarine. The brown background and the brown hair have in common high contents of iron oxides and titanium white (admixed with barite and strontium sulfide). The use of vermillion is prominent only in the nose and in the lips.
A colorized reconstruction of the feet part, built on the basis of the overall information collected in the present study, is proposed in Fig. 7. Color hue has been identified by looking at the right edge of the painting while contours and shadows have been obtained by looking at the Zn and Pb MA-XRF scans (Fig. 6).