Monet Paintings and Drawings at the Art Institute of Chicago

Technical Report

Technical Summary

Claude Monet’s Charing Cross Bridge, London was executed on a pre-primed, no. 30 landscape (paysage) standard-size linen canvas. The painting appears to retain its original stretcher. The number 30 stenciled on the back of the stretcher probably refers to the stretcher size. The ground is off-white and consists of a single layer. A warp-thread match was determined with two other paintings in the Art Institute’s collection: Stack of Wheat (Snow Effect, Overcast Day) (cat. 30 [W1281], inv. 1933.1155) and The Customs House at Varengeville (cat. 35 [W1455], inv. 1933.1149), suggesting that the fabric for these paintings came from the same bolt of fabric.2 The painting has a heavily brush marked surface. Crisp brushstrokes introduced in the earlier paint layers remain visible on the surface through the thin, fluid brushstrokes applied on top. In some places, the canvas texture remains prominent through light applications of paint that deposited mainly on the peaks of the canvas weave. The artist also appears to have scraped or wiped the upper paint layers in localized areas, revealing colors from underneath. In some places, small areas of interlayer cleavage have resulted, due to poor adhesion between the layers. The artist made a significant change in the perspective of the scene. The technical examination shows that major compositional elements, including the bridge supports, the bridge house, the embankment, and the buildings were all originally painted further left of their positions in the final painting. In addition, more of Westminster Bridge, in the distance, was originally included, its arches initially extending further to the left edge of the canvas. The painting was originally signed at the lower left corner. This signature was then painted over, probably in conjunction with further reworking of the painting, and then signed again in the lower-right corner.3

Multilayer Interactive Image Viewer

The multilayer interactive image viewer is designed to facilitate the viewer’s exploration and comparison of the technical images (fig. 40.1).4

Signature

Signed and dated: Claude Monet 1901 (lower right, in blue paint5) (fig. 40.2). Some of the strokes of pale-pinkish-purple paint were still wet when the signature was applied. These strokes may represent finishing touches added by the artist before signing the painting.6

At the lower left corner, there are traces of another signature that was subsequently painted over (fig. 40.3). This signature was also executed in blue paint (fig. 40.4). It is difficult to make out the second half of the signature, which may indicate that the paint was at least partially scraped or wiped away before subsequent paint layers were applied. It is not clear whether the painting was also dated in this area, but microscopic traces of similar blue paint extend sufficiently far to the right to suggest this possibility. It looks like the signature was dry when the yellowish-green paint from the water was applied on top. It is clear that some wiping or scraping of the paint surface, similar to that observed elsewhere in the painting (see Application/technique), occurred after the signature was painted out. The paint appears flattened and abraded in areas, with underlying layers exposed at the surface. There are small, localized areas of associated interlayer cleavage where separation has occurred between the upper, yellowish-green paint and the lower paint layers including the signature (fig. 40.5). The pale-pink and pale-purple strokes of the water were applied after the abrasion and interlayer cleavage had occurred.

Structure and Technique

Support

Canvas

Flax (commonly known as linen).7

Standard format

The dimensions correspond closely to a no. 30 landscape (paysage) standard-size stretcher (65 × 92 cm).8

Weave

Plain weave. Average thread count (standard deviation): 23.4V (0.6) × 20.9H (0.7) threads/cm; the vertical threads were determined to correspond to the warp and the horizontal threads to the weft.9 A warp-thread match was found with Stack of Wheat (Snow Effect, Overcast Day) (cat. 30 [W1281], inv. 1933.1155) and The Customs House at Varengeville (cat. 35 [W1455], inv. 1933.1149).10

Canvas characteristics

There is mild cusping along the top and bottom edges of the canvas, moderate cusping on the left edge, and more pronounced and irregular cusping along the right edge.

Stretching

The painting appears to retain its original stretching. The canvas is attached with iron tacks11 spaced 5.5–7.5 cm apart. The cusping corresponds to the placement of the original tacks. There are a few additional small holes on each tacking edge, which appear to be more recent. Excess canvas wraps around the back edge of the stretcher on all sides.

Stretcher/strainer

The painting appears to retain its original stretcher (fig. 40.6). It is five membered with a vertical crossbar and keyable, mortise and tenon joints. All ten keys are present (lower crossbar key broken but still functional). Dimensions: outer depth, 2.0 cm; inner depth, 1.8 cm; stretcher-bar width, 6.0 cm (left, right, and bottom), 6.4 cm (top); crossbar depth, 1.3 cm; crossbar width, 6.2 cm.

Manufacturer’s/supplier’s marks

The number 30 is stenciled on the back of the stretcher (fig. 40.7). This probably refers to the standard-size stretcher.

Preparatory Layers

Sizing

Not determined (probably glue).12

Ground application/texture

The ground layer extends to the edges of all four tacking margins, indicating that the canvas was cut from a larger piece of primed fabric, which was probably commercially prepared. Cross-sectional analysis indicates that the ground consists of a single layer that ranges from approximately 20 to 105 µm in thickness (fig. 40.8).

Color

The ground is off-white, with some dark and possibly red or brown particles visible under magnification (fig. 40.9).

Materials/composition

Analysis indicates that the ground contains lead white and calcium carbonate (chalk)13 with traces of alumina, silica, and various silicates.14 Binder: Oil (estimated).

Compositional Planning/Underdrawing/Painted Sketch

Extent/character

No underdrawing was observed with infrared reflectography (IRR) or microscopic examination.

Paint Layer

Application/technique and artist’s revisions

The painting was densely built up over most of the surface, as evidenced by the relative radio-opacity of much of the paint layer in the X-ray (fig. 40.10). The paint layers are continuous, completely concealing the ground layer, except near the edges of the work. The thick buildup of paint is partly related to the fact that the artist made significant changes to the placement of the major compositional elements. The vertical supports of Charing Cross Bridge, as well as the bridge house, the embankment in the lower right corner,15 and the towers of the Houses of Parliament were all originally painted to the immediate left of their final positions. The outlines of the earlier forms are most clearly seen when the painting is viewed in transmitted light (fig. 40.11). With the use of transmitted infrared, the horizontal line of the railroad tracks can be seen to continue straight across to the right edge of the canvas, underneath the bridge house in the final painting (fig. 40.12). In addition, the perspective of Westminster Bridge, faintly visible in the distance, was also altered slightly: the arches painted in the earlier composition are offset from their position in the final painting; and, in the earlier painting, five or six arches were depicted, continuing further to the left edge of the painting, underneath the area later covered by the steam from the train (fig. 40.13). These changes suggest that the artist shifted his viewpoint of the scene and that the steam train on Charing Cross Bridge may not have been conceived for the first composition or, at least, was not incorporated early in the painting process.

Overall, the painting is relatively flat with no impasto. It does, however, have a heavily brush marked surface (fig. 40.14). Much of this texture was introduced in the early painting stages; for example, the crisp horizontal strokes that run through broad areas of the sky (fig. 40.15) and the crisscrossed strokes in the water (fig. 40.16), the texture of which remain evident through the subsequent buildup of paint layers applied on top. These underlying strokes appear to be related to the earlier composition, as they seem to conform to the edges of the painted-out forms. For example, the horizontal brush marks in the sky, which pass underneath the towers of the Parliament buildings in the final painting, seem to stop on either side of the earlier towers that were painted out (fig. 40.17). Further texture was incorporated into the paint surface through the artist’s use of different paint applications and treatments. For example, a corrugated texture was created in some areas through the successive buildup of paint layers that were lightly applied and deposited mainly on the high points of the canvas weave (fig. 40.18, fig. 40.19). In some areas, slightly thicker and more fluid paint applications provide a relatively smooth, flat surface, obscuring much of the texture of the layers underneath (fig. 40.20). In localized areas, including the steam from the train, the fluid paint was worked wet-into-wet (fig. 40.21, fig. 40.22). In other areas, the artist appears to have lightly scraped or wiped the upper layers, breaking up the paint surface by locally revealing colors from underlying layers (fig. 40.23, fig. 40.24).16 This is especially visible in parts of the sky, where the abrasion reveals the peaks of the lighter-hued, horizontal brushstrokes from underneath (fig. 40.25, fig. 40.26). Often, in association with the scraping or wiping, some interlayer cleavage has occurred (fig. 40.27). For the most part, the underlying paint looks like it was already dry when it was painted over, as the ridges of the brush marks remained undisturbed. This probably resulted in weak adhesion between the layers, leading to separation when the artist worked back into the surface (fig. 40.28). The edges of the interlayer cleavage losses appear soft, suggesting that the upper paint layers were still somewhat fluid when the cleavage occurred (fig. 40.29). Some final paint strokes were applied over these localized areas of interlayer cleavage, including parts of the final signature, and the isolated purple strokes that skip across the surface of the sky. There are several small inclusions (possibly dried paint picked up on the brush) embedded in the paint layer.

Painting tools

Brushes, including 1.0 and 2.0 cm width, flat ferrule (based on width and shape of brushstrokes). Several brush hairs are embedded in the paint layers.

Palette

Analysis indicates the presence of the following pigments: lead white, cadmium yellow, vermilion, red lake, emerald green, viridian, cobalt blue, ultramarine blue, and cobalt violet.17

Binding media

Oil (estimated).18

Surface Finish

Varnish layer/media

The painting was cleaned in 1993 and left unvarnished (see Conservation History). It has a soft yet variable surface, with relatively matte passages as well as areas of smooth, fluid paint application that have a slightly glossy sheen. In 1971, the painting was reported to have a discolored and yellowed, soft resin varnish layer; its origin is unknown.19

Conservation History

The 1972 pretreatment notes state that there were scattered abrasions, especially in the left sky and foreground, which had previously been overpainted.20 There is some evidence of this in the 1971 pretreatment UV photograph in the sky at upper left, but more apparent is the minor inpainting visible in the sky, right of center and at the upper right edge. All of this retouching appears to be related to the interlayer cleavage resulting from the artist’s technique of scraping or wiping the paint surface (see Application/technique).

In 1972, discolored surface films and overpaint were removed. A layer of polyvinyl acetate (PVA) AYAA was applied. Paint losses were inpainted. A layer of methacrylate resin L-46 was applied, followed by a final layer of AYAA.21

In 1991, the synthetic varnish layers and previous retouching were removed. Three small interlayer cleavage losses in the sky at upper left were inpainted.22

Condition Summary

The painting is in near-pristine condition. It is unlined and appears to retain its original stretcher and tacking. The canvas is stretched taut and is relatively planar, except for mild draws at the upper left, lower left, and lower right corners. The paint layer is in excellent condition. Small areas of interlayer cleavage throughout the painting appear to be related to the artist’s technique (i.e., possible scraping) (see Application/technique). There is mild abrasion in the ground and paint layers at the edges, with minor, associated retouching along the left edge. Other areas of retouching—in the sky at upper left and near the lower left corner—appear to be related to the interlayer cleavage losses. There are localized areas of fine cracking, which are only visible under magnification. A few localized areas of microscopic wrinkling were observed in areas of more-fluid paint application. The painting is currently unvarnished.
Kimberley Muir

Frame

The current frame appears to be original to the painting. It is a French (Parisian), early-twentieth-century, Durand-Ruel, Régence Revival, ogee frame with cast foliate and center cartouches with cabochon centers on a quadrillage bed, leaf-tip-and-shell sight molding and a nonoriginal independent fillet liner. The frame has both water and oil gilding. The liner has been painted gold. Red bole was used on the perimeter molding, the cast foliate on the ogee and sight molding, and the scotia sides. Red-orange bole was used on the sanded frieze and bordering fillets. No bole was applied to the quadrillage bed of the ogee face. The ornament and sight molding are selectively burnished. The frame has an overall light brass tone with an even toning wash, on top of which casein or gouache raw umber and gray washes and dark flecking were applied. The frame has a glued poplar substrate that is mitered and nailed with glued half-lap braces with a cast plaster face. At a later date the original back of the frame was planed flat, removing all construction history and provenance. A back frame was then glued to the back and all back and interior surfaces were painted. The molding, from perimeter to interior, is fillet with stylized, running undulating bands with rhomboid center punches; scotia side; ogee face with a cast quadrillage bed and center and corner foliate and floral cartouches with cabochon centers on a double-lined diamond bed with punched centers; fillet; sanded front frieze; fillet; ogee with stylized leaf-tip-and-shell sight molding; and an independent fillet liner with cove sight (fig. 40.30, fig. 40.31).23
Kirk Vuillemot