Technique and condition
This work is on medium weight, wove grey paper made by Bally, Ellan and Steart at the De Montalt Mill in Bath, Somerset. The paper has a ‘B E & S’ watermark, and countermark ‘1829’. Turner has applied thin washes of colour to the wet paper in broadly horizontal sweeps, and then sketched the topography very cursorily over the paint in graphite pencil. He worked up the foreground with more localised and more intensely coloured washes but no more drawing, and finally freely worked on the sky. Here he layered lead white gouache and then pale chrome yellow for the sunset, using the same technique as in his oil paintings, to maximise the brilliance of the pale yellow. Some of the thinnest areas of chrome yellow appear to have darkened. Turner was an early user of lead white in gouache, and by the middle of the nineteenth century other artists were also using it regularly. Lead white in scanty amounts of gum water as Turner used it, can easily discolour to a speckled or solid dark brown when it reacts with hydrogen sulphide gas, a common urban pollutant during the nineteenth century. Here, the chrome yellow may have behaved in the same way, since it is unevenly coloured now. The colour change begins in an extremely thin surface layer: in oil paints which can be sampled for cross-sections, such a layer is so very thin that it cannot be seen even with a high-quality optical microscope. Thinly applied layers of paint are more likely to reveal the change, because there is less unaltered material underneath. Chrome yellows were greatly mistrusted in Turner’s day on account of such colour changes, but in fact these changes can rarely be observed with certainty in his watercolours or oil paintings.
Scratching-out has been done with a soft point, in a few areas. White highlights in the foreground were applied in a rather insubstantial-looking white paint that probably is not based on lead white. Such paint, unprotected by other layers, would probably have darkened in the same way as the chrome yellow in the sky.
- River Danube(125)