near the Jas de Bouffan as models. They are not genre pictures, even if they show scenes from everyday life; the motif is constructed according to strict laws of colour and form. The area around the Montagne Sainte-Victoire was one of the most important themes of his later years. From a vantage point above his studio, later called Terrain des Paintres, he painted several views of the mountain. A precise observation of nature was a prerequisite for Cézanne's painting: "In order to paint a landscape correctly, I first have to recognize the geological stratification." In total he painted more than 30 oil paintings and 45 watercolours of the mountains, and he wrote to a friend in the 1890s "art is a harmony parallel to nature". Cézanne was primarily concerned with watercolour painting in his late work, as he realized that the specific application of his method could be particularly evident in this medium. The late watercolours also had an effect on his oil paintings, for example in the study with bathers (1902–1906), in which a depiction full of “empty spaces” flanked by colour appears to be complete. The painter and art critic Roger Fry emphasized this in his seminal Cézanne publication Cézanne: A Study of His Development from 1927 that after 1885 the watercolour technique had a strong influence on his painting with oil paints. The watercolours in Vollard's Cézanne monograph of 1914 and in Julius Meier-Graefe's picture portfolio edited in 1918 with ten facsimiles based on the watercolours became known to a larger group of interested parties. Only lightly coloured pencil studies, which occasionally appeared in sketch albums, stand next to carefully coloured works. Many watercolours are equal to the realizations on canvas and form an autonomous group of works. In terms of subject matter, landscape watercolours dominate, followed by figure paintings and still lifes, while portraits, in contrast to paintings and drawings, are rarer. Method Artistic style Cézanne's early work is often concerned with the figure in the landscape and includes many paintings of groups of large, heavy figures in the landscape, imaginatively painted. Later in his career, he became more interested in working from direct observation and gradually developed a light, airy painting style. Nevertheless, in Cézanne's mature work there is the development of a solidified, almost architectural style of painting. Throughout his life he struggled to develop an authentic observation of the seen world by the