June 1881
Vincent continues to systematically work through the exercises in his art instruction manuals. He also ventures outside to render marshland, windmills, and thatched cottages. He acquires a copy of Traité d’aquarelle, Armand-Théophile Cassagne’s textbook on watercolor.
He experiments with graphite heightened by pen, india ink, and Conté crayon. He uses a reed pen to create broader lines and finds that Ingres paper works especially well with pen-and-ink. He tries adding watercolor and black and green chalk to some of his landscapes.
– Alisia Robin Coon, Van Gogh Timeline, in Becoming van Gogh, Denver Art Museum, 2012, 238