Left: Vincent van Gogh, 'Still Life with a Plate of Onions', Early January 1889. Oil on canvas, 49.6 x 64.4 cm. Kröller-Müller Museum, Otterlo, The Netherlands.

Right: Vincent van Gogh, 'The Sower', November 1888. Oil on canvas, 32 x 40 cm. Van Gogh Museum, Amsterdam (Vincent van Gogh Foundation)

Paul Sandby, 'The North Terrace, Windsor Castle, Looking West' (detail), c.1765. Bodycolour over graphite 379 x 545 mm. Yale Center for British Art, New Haven, Paul Mellon Collection