Simon Denis, 'Sunset in the Roman Campagna', about 1800

Painted around 1800, this small oil sketch on canvas by the Belgian artist Simon Denis is a fine example of the type of study produced by artists working in Italy from about 1780 to 1850, who painted swiftly and directly from nature. Corot’s The Roman Campagna, with the Claudian Aqueduct, painted in the same region some 25 years later, is another excellent example. Most of these studies were unsigned and undated, but an inscription on the back of this picture confirms it is by Denis, who was in Rome from 1786 to about 1803.

Soon after Denis arrived in Rome, having previously studied in Paris, his work began to attract attention. Although his finished landscapes tended to be exercises in finely detailed late eighteenth-century classicism, he was also well-known for his outdoor sketching. The relative freedom of these oil studies is very different from his more formal landscapes and Denis was particularly praised for his ability to capture fleeting atmospheric effects. While in Paris, he may have met the painter and writer Pierre-Henri de Valenciennes, who had recently returned from Rome where he had been working for four years. Valenciennes’s treatise on painting outdoors, Éléments de perspective pratique (published in 1800), was to influence many artists, including Corot. It would seem that Denis, in his studies of Roman rooftops, rocks and skies, was also following Valenciennes’s advice.

Denis’s oil studies are often of dramatic scenes from nature, particularly the spectacle of the sun setting behind stormy clouds, which allowed him to show various intense light effects. In this sketch, a thin strip of grey-green land at the bottom of the picture, which is otherwise filled by the expansive sky, anchors the composition and gives it scale – a device also used by Valenciennes. In the distance, some dark grey-brown buildings, possibly ruins, are silhouetted against the horizon. Their function, perhaps, is also to give a sense of scale and provide a focal point to the setting sun, which is hidden by a purple-grey cloud. Although the sun itself cannot be seen directly, shafts of pale yellow and pink sunlight radiate from behind the cloud.

The entire sketch has been rapidly painted – most likely in under an hour – and Denis adjusts the handling of the paint according to the area he is working on The paint itself ranges from just a thin coating – for example the initial ground colour which you can still see in places – to the thick impasto cream and yellow paint used to highlight the upper edges of the clouds in the picture’s centre, which evoke the brilliance of the sunlight behind them. The grey clouds have a textured appearance, as if the paint has been stippled on, using the end of the brush, rather than brushed on smoothly. The sky and the sun’s rays, however, are painted with long fluid strokes. These shafts of sunlight vary from quite thickly painted strokes of yellow and pink to more delicate strokes used for the vertical rays directly above the cloud. To the right, Denis has painted a broad ray, which cuts diagonally across the grey clouds, using just a single unbroken upward stroke of a wide brush.